{"dp_type": "Dataset", "free_text": "Sediment"}
[{"awards": "2147045 Learman, Deric", "bounds_geometry": null, "date_created": "Mon, 16 Dec 2024 00:00:00 GMT", "description": "Shelf sediment samples were collected in Eastern Antarctica with the mega corer in 2023 (April). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set.", "east": null, "geometry": null, "keywords": "Antarctica; Cryosphere", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Learman, Deric", "project_titles": "Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments", "projects": [{"proj_uid": "p0010373", "repository": "USAP-DC", "title": "Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Physical and geochemical data from shelf sediments eastern Antarctica", "uid": "601876", "west": null}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((117 -66,119.9 -66,122.8 -66,125.7 -66,128.6 -66,131.5 -66,134.4 -66,137.3 -66,140.2 -66,143.1 -66,146 -66,146 -66.1,146 -66.2,146 -66.3,146 -66.4,146 -66.5,146 -66.6,146 -66.7,146 -66.8,146 -66.9,146 -67,143.1 -67,140.2 -67,137.3 -67,134.4 -67,131.5 -67,128.6 -67,125.7 -67,122.8 -67,119.9 -67,117 -67,117 -66.9,117 -66.8,117 -66.7,117 -66.6,117 -66.5,117 -66.4,117 -66.3,117 -66.2,117 -66.1,117 -66))"], "date_created": "Mon, 21 Oct 2024 00:00:00 GMT", "description": "Totten Glacier is the termination of the largest marine-based portion of the East Antarctic Ice Sheet, the Aurora Subglacial Basin. Yet little is known about the glacial evolution of the catchment and the factors influencing its present and past behavior. Due its remote location and heavy sea ice, the continental shelf in front of the Totten Glacier had not been comprehensively surveyed prior to this study. Satellite observations indicate that the Totten ice drainage system is thinning, and it has been hypothesized that this thinning is in response to undermelting by warm ocean waters over the continental shelf. While this process is observed elsewhere in Antarctica (e.g. the rapidly retreating Pine Island Glacier in West Antarctica), the Totten Glacier system is potentially Antarcticas most important glacial drainage system due to its large size; it is three times larger than any system in West Antarctica. \u003c/br\u003eThe main goals of this proposal were: \u003c/br\u003eTo generate multibeam bathymetric maps of the continental shelf proximal to the Totten Glacier system to understand the recent regional glacial history and to document the pathways, if any, for circumpolar deep water to move onto the shelf. \u003c/br\u003eTo conduct a physical oceanographic survey of the region proximal to the Totten Glacier system, to determine the presence, if any, of warm ocean waters over the continental shelf.\u003c/br\u003eTo conduct a seismic survey of the continental shelf to assess the long-term evolution of the glacial system in the Aurora Subglacial Basin.\u003c/br\u003eTo collect marine sediment cores to determine the regional deglacial to Holocene climate history and the influence of warm circumpolar deep water.", "east": 146.0, "geometry": ["POINT(131.5 -66.5)"], "keywords": "Antarctica; Cryosphere; Diatom; NBP1402; Totten Glacier", "locations": "Totten Glacier; Antarctica; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy; NBP1402 science party, ", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "NBP1402 diatom data", "uid": "601845", "west": 117.0}, {"awards": "1939146 Siddoway, Christine", "bounds_geometry": ["POLYGON((-109.1 -68.6,-108.94 -68.6,-108.78 -68.6,-108.61999999999999 -68.6,-108.46 -68.6,-108.3 -68.6,-108.14 -68.6,-107.98 -68.6,-107.82 -68.6,-107.66 -68.6,-107.5 -68.6,-107.5 -68.64,-107.5 -68.67999999999999,-107.5 -68.72,-107.5 -68.75999999999999,-107.5 -68.8,-107.5 -68.84,-107.5 -68.88,-107.5 -68.92,-107.5 -68.96,-107.5 -69,-107.66 -69,-107.82 -69,-107.98 -69,-108.14 -69,-108.3 -69,-108.46 -69,-108.61999999999999 -69,-108.78 -69,-108.94 -69,-109.1 -69,-109.1 -68.96,-109.1 -68.92,-109.1 -68.88,-109.1 -68.84,-109.1 -68.8,-109.1 -68.75999999999999,-109.1 -68.72,-109.1 -68.67999999999999,-109.1 -68.64,-109.1 -68.6))"], "date_created": "Tue, 27 Aug 2024 00:00:00 GMT", "description": "The table contains sample identifiers, location data, and geochronology data (U-Pb zircon dates; apatite fission track determinations) from selected intervals of sediment cores obtained at sites U1532 (A, B, C, G) and U1533 (A, B) recovered during IODP Expedition 379 to the outer Amundsen Sea, Antarctica.", "east": -107.5, "geometry": ["POINT(-108.3 -68.8)"], "keywords": "Amundsen Sea; Antarctica; Cryosphere; Geochronology; Marie Byrd Land; Subglacial Bedrock; Thermochronology", "locations": "Antarctica; Marie Byrd Land; Amundsen Sea; Amundsen Sea", "north": -68.6, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Siddoway, Christine", "project_titles": "Collaborative Research: Testing the Linchpin of WAIS Collapse with Diatoms and IRD in Pleistocene and Late Pliocene Strata of the Resolution Drift, Amundsen Sea, Antarctica", "projects": [{"proj_uid": "p0010451", "repository": "USAP-DC", "title": "Collaborative Research: Testing the Linchpin of WAIS Collapse with Diatoms and IRD in Pleistocene and Late Pliocene Strata of the Resolution Drift, Amundsen Sea, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.0, "title": "U-Pb zircon and apatite fission track dates for IRD (ice-rafted cobbles and mineral grains) from IODP379 drill sites", "uid": "601828", "west": -109.1}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POLYGON((100 -62,104.4 -62,108.8 -62,113.2 -62,117.6 -62,122 -62,126.4 -62,130.8 -62,135.2 -62,139.6 -62,144 -62,144 -64,144 -66,144 -68,144 -70,144 -72,144 -74,144 -76,144 -78,144 -80,144 -82,139.6 -82,135.2 -82,130.8 -82,126.4 -82,122 -82,117.6 -82,113.19999999999999 -82,108.8 -82,104.4 -82,100 -82,100 -80,100 -78,100 -76,100 -74,100 -72,100 -70,100 -68,100 -66,100 -64,100 -62))"], "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "This dataset includes quantitative diatom assemblage data from 60 samples from IODP Site U1357B on the Adelie Basin. The record spans from 11,000 yBP to present.", "east": 144.0, "geometry": ["POINT(122 -72)"], "keywords": "Antarctica; Cryosphere; Geochemistry; Sediment; Wilkes Land", "locations": "Antarctica; Wilkes Land", "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.0, "title": "Diatom assemblage from IODP Site U1357", "uid": "601818", "west": 100.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POLYGON((100 -62,104.4 -62,108.8 -62,113.2 -62,117.6 -62,122 -62,126.4 -62,130.8 -62,135.2 -62,139.6 -62,144 -62,144 -64,144 -66,144 -68,144 -70,144 -72,144 -74,144 -76,144 -78,144 -80,144 -82,139.6 -82,135.2 -82,130.8 -82,126.4 -82,122 -82,117.6 -82,113.19999999999999 -82,108.8 -82,104.4 -82,100 -82,100 -80,100 -78,100 -76,100 -74,100 -72,100 -70,100 -68,100 -66,100 -64,100 -62))"], "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and total nitrogen (wt%) from 121 samples from IODP Site U1357B in the Adelie Basin. The sediments are Holocene age (11 kyBP to present).", "east": 144.0, "geometry": ["POINT(122 -72)"], "keywords": "Antarctica; Cryosphere; Wilkes Land", "locations": "Antarctica; Wilkes Land", "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel; Kelly, Roger; Robinson, Rebecca", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.0, "title": "Diatom-bound and bulk sedimentary nitrogen isotopes from IODP Site U1357", "uid": "601817", "west": 100.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POLYGON((-80 -59,-76.8 -59,-73.6 -59,-70.4 -59,-67.2 -59,-64 -59,-60.8 -59,-57.599999999999994 -59,-54.4 -59,-51.2 -59,-48 -59,-48 -60.6,-48 -62.2,-48 -63.8,-48 -65.4,-48 -67,-48 -68.6,-48 -70.2,-48 -71.8,-48 -73.4,-48 -75,-51.2 -75,-54.4 -75,-57.6 -75,-60.8 -75,-64 -75,-67.2 -75,-70.4 -75,-73.6 -75,-76.8 -75,-80 -75,-80 -73.4,-80 -71.8,-80 -70.2,-80 -68.6,-80 -67,-80 -65.4,-80 -63.8,-80 -62.2,-80 -60.6,-80 -59))"], "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and total nitrogen (wt%) from 81 Holocene and late deglacial-aged samples from ODP Site 1098B on the western Antarctic Peninsula.", "east": -48.0, "geometry": ["POINT(-64 -67)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Geochemistry; Sediment", "locations": "Antarctica; Antarctic Peninsula", "north": -59.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel; Jones, Colin; Kelly, Roger; Robinson, Rebecca", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Diatom-bound and bulk sedimentary N isotopes from ODP Site 1098, Western Antarctic Peninsula", "uid": "601816", "west": -80.0}, {"awards": "2000992 Romans, Brian", "bounds_geometry": ["POLYGON((-174 -74.1667,-173.93 -74.1667,-173.86 -74.1667,-173.79 -74.1667,-173.72 -74.1667,-173.65 -74.1667,-173.58 -74.1667,-173.51000000000002 -74.1667,-173.44 -74.1667,-173.37 -74.1667,-173.3 -74.1667,-173.3 -74.25503,-173.3 -74.34336,-173.3 -74.43169,-173.3 -74.52002,-173.3 -74.60835,-173.3 -74.69668,-173.3 -74.78501,-173.3 -74.87334,-173.3 -74.96167,-173.3 -75.05,-173.37 -75.05,-173.44 -75.05,-173.51000000000002 -75.05,-173.58 -75.05,-173.65 -75.05,-173.72 -75.05,-173.79 -75.05,-173.86 -75.05,-173.93 -75.05,-174 -75.05,-174 -74.96167,-174 -74.87334,-174 -74.78501,-174 -74.69668,-174 -74.60835,-174 -74.52002,-174 -74.43169,-174 -74.34336,-174 -74.25503,-174 -74.1667))"], "date_created": "Wed, 10 Jul 2024 00:00:00 GMT", "description": "This data set includes grain size information from late Pliocene through Pleistocene aged sediment recovered in cores from International Ocean Discovery Program (IODP) Expedition 374 Sites U1524 and U1525, on the continental slope and rise of the Ross Sea margin. There are two types of particle size data: (1) laser diffraction (Mastersizer 3000) data of silt-range sediment subsampled from mm-scale thick laminae/beds, and (2) x-ray-monitored settling (SediGraph 5120) data from muddy intervals directly overlying the silt laminae/beds. For Site U1524, there are 100 samples of Mastersizer data coupled with 100 samples of SediGraph data. For Site U1525, there are 50 samples of Mastersizer data coupled with 50 samples of SediGraph data. For both sites, the analyzed samples span the depth range of the core that contains the silty laminae/beds. ", "east": -173.3, "geometry": ["POINT(-173.65 -74.60835)"], "keywords": "Antarctica; Cryosphere; Grain Size; Ross Sea", "locations": "Ross Sea; Antarctica", "north": -74.1667, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Romans, Brian W.; Varela, Natalia", "project_titles": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene", "projects": [{"proj_uid": "p0010227", "repository": "USAP-DC", "title": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.05, "title": "Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea", "uid": "601807", "west": -174.0}, {"awards": "2042495 Blackburn, Terrence; 1644171 Blackburn, Terrence", "bounds_geometry": ["POLYGON((161.9 -77.65,161.96 -77.65,162.02 -77.65,162.08 -77.65,162.14000000000001 -77.65,162.2 -77.65,162.26 -77.65,162.32 -77.65,162.38 -77.65,162.44 -77.65,162.5 -77.65,162.5 -77.66000000000001,162.5 -77.67,162.5 -77.68,162.5 -77.69,162.5 -77.7,162.5 -77.71000000000001,162.5 -77.72,162.5 -77.73,162.5 -77.74,162.5 -77.75,162.44 -77.75,162.38 -77.75,162.32 -77.75,162.26 -77.75,162.2 -77.75,162.14000000000001 -77.75,162.08 -77.75,162.02 -77.75,161.96 -77.75,161.9 -77.75,161.9 -77.74,161.9 -77.73,161.9 -77.72,161.9 -77.71000000000001,161.9 -77.7,161.9 -77.69,161.9 -77.68,161.9 -77.67,161.9 -77.66000000000001,161.9 -77.65))"], "date_created": "Mon, 01 Jul 2024 00:00:00 GMT", "description": "This dataset contains uranium and thorium isotopic compositions (U-234, U-235, U-238, Th-230, Th-232) and major element compositions (Al, K, Na, Ca, Fe, Mn, reported as oxides) for silicate sediments from glaciogenic drifts associated with advances of Taylor Glacier in Taylor Valley, Antarctica. Isotopic measurements were obtained by ID-TIMS in the Keck Isotope Facility at UC Santa Cruz and elemental measurements were obtained by ICP-OES in the Plasma Analytical Laboratory. All measurements include fully propagated analytical and systematic (e.g. isotopic tracer) uncertainties. Chemical index of alteration was calculated from major element data. Prior to measurements, sediments were sieved to \u2264125 \u03bcm grain sizes, separated into quartz-feldspar-rich and clay-rich aliquots by hydraulic settling, and subjected to sequential chemical extractions (\"leaching\") prior to silicate digestion.", "east": 162.5, "geometry": ["POINT(162.2 -77.7)"], "keywords": "Antarctica; Cryosphere; Erosion; Isotope Data; Major Elements; Soil; Taylor Glacier; Taylor Valley", "locations": "Taylor Glacier; Antarctica; Taylor Valley", "north": -77.65, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Edwards, Graham; Piccione, Gavin; Blackburn, Terrence; Tulaczyk, Slawek", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates; U-Series Comminution Age Constraints on Taylor Valley Erosion", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}, {"proj_uid": "p0010243", "repository": "USAP-DC", "title": "U-Series Comminution Age Constraints on Taylor Valley Erosion"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.75, "title": "U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "uid": "601806", "west": 161.9}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POINT(-64.207 -64.86)"], "date_created": "Wed, 24 Apr 2024 00:00:00 GMT", "description": "This dataset includes measurements of opal (wt %), total organic carbon (wt %), total nitrogen (wt%), bulk nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air) from 36 samples from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments were deposited during a period of deglaciation about 12.5-12.3 ka.", "east": -64.207, "geometry": ["POINT(-64.207 -64.86)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "locations": "Antarctic Peninsula; Antarctica", "north": -64.86, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.86, "title": "Sediment chemistry of ODP Site 1098", "uid": "601778", "west": -64.207}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POINT(-64 -65)"], "date_created": "Wed, 24 Apr 2024 00:00:00 GMT", "description": "This dataset includes diatom assemblage and surface area data from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments are laminated and were deposited during a period of deglaciation about 12.5-12.3 ka. Quantitative diatom assemblage counts and surface area measurements are reported for 12 samples.", "east": -64.0, "geometry": ["POINT(-64 -65)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Sediment Core Data", "locations": "Antarctic Peninsula; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "ODP Site 1098 deglacial diatom assemblage", "uid": "601777", "west": -64.0}, {"awards": "2044924 Barrett, John", "bounds_geometry": ["POLYGON((161.70776367188 -77.519802097166,161.899475097661 -77.519802097166,162.091186523442 -77.519802097166,162.282897949223 -77.519802097166,162.474609375004 -77.519802097166,162.666320800785 -77.519802097166,162.858032226566 -77.519802097166,163.049743652347 -77.519802097166,163.241455078128 -77.519802097166,163.433166503909 -77.519802097166,163.62487792969 -77.519802097166,163.62487792969 -77.54867059480199,163.62487792969 -77.57753909243799,163.62487792969 -77.606407590074,163.62487792969 -77.63527608771,163.62487792969 -77.664144585346,163.62487792969 -77.69301308298199,163.62487792969 -77.72188158061799,163.62487792969 -77.750750078254,163.62487792969 -77.77961857589,163.62487792969 -77.808487073526,163.433166503909 -77.808487073526,163.241455078128 -77.808487073526,163.049743652347 -77.808487073526,162.858032226566 -77.808487073526,162.666320800785 -77.808487073526,162.474609375004 -77.808487073526,162.282897949223 -77.808487073526,162.091186523442 -77.808487073526,161.899475097661 -77.808487073526,161.70776367188 -77.808487073526,161.70776367188 -77.77961857589,161.70776367188 -77.750750078254,161.70776367188 -77.72188158061799,161.70776367188 -77.69301308298199,161.70776367188 -77.664144585346,161.70776367188 -77.63527608771,161.70776367188 -77.606407590074,161.70776367188 -77.57753909243799,161.70776367188 -77.54867059480199,161.70776367188 -77.519802097166))"], "date_created": "Wed, 03 Apr 2024 00:00:00 GMT", "description": "Microbial communities are the primary drivers of carbon cycling in the McMurdo Dry Valleys of Antarctica. Dense microbial mats, consisting mainly of photosynthetic cyanobacteria, occupy aquatic areas associated with streams and lakes. Other microbial communities also occur at lower densities as patchy surface biological soil crusts (biocrusts) across the terrestrial landscape. Multispectral satellite data have been used to model microbial mat abundance in high-density areas like stream and lake margins, but no previous studies had investigated the lower detection limits of biocrusts. Here, we describe remote sensing and field-based survey and sampling approaches to study the detectability and distribution of biocrusts in the McMurdo Dry Valleys. Using a combination of multi- and hyperspectral tools and spectral linear unmixing, we modeled the abundances of biocrust in eastern Taylor Valley. Our spectral approaches can detect low masses of biocrust material in laboratory microcosms down to biocrust concentrations of 1% by mass. These techniques also distinguish the spectra of biocrust from both surface rock and mineral signatures from orbit. We found that biocrusts are present throughout the soils of eastern Taylor Valley and are associated with diverse underlying soil communities. The densest biocrust communities identified in this study had total organic carbon 5x greater than the content of typical arid soils. The most productive biocrusts were located downslope of melting snowpacks in unique soil ecosystems that are distinct from the surrounding arid landscape. There are similarities between the snowpack and stream sediment communities (high diversity of soil invertebrates) as well as their ecosystem properties (e.g., persistence of liquid water, high transfer of available nutrients, lower salinity from flushing) compared to the typical arid terrestrial ecosystem of the dry valleys. Our approach extends the capability of orbital remote sensing of photosynthetic communities out of the aquatic margins and into the drier soils which comprise most of this landscape. This interdisciplinary work is critical for measuring and monitoring terrestrial carbon stocks and predicting future ecosystem dynamics in this currently water-limited but increasingly dynamic Antarctic landscape, which is particularly climate-sensitive and difficult to access.\r\n", "east": 163.62487792969, "geometry": ["POINT(162.666320800785 -77.664144585346)"], "keywords": "Antarctica; Carbon; Cryosphere; McMurdo Dry Valleys; Snow", "locations": "McMurdo Dry Valleys; Antarctica", "north": -77.519802097166, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Barrett, John", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -77.808487073526, "title": "Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica", "uid": "601773", "west": 161.70776367188}, {"awards": "2013987 Zoet, Lucas", "bounds_geometry": null, "date_created": "Wed, 13 Dec 2023 00:00:00 GMT", "description": "This dataset contains AMS results and microstructure analysis from different depths within the sheared till.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Zoet, Lucas", "project_titles": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory", "projects": [{"proj_uid": "p0010434", "repository": "USAP-DC", "title": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Ring shear bed deformation measurements", "uid": "601757", "west": null}, {"awards": "2013987 Zoet, Lucas", "bounds_geometry": null, "date_created": "Thu, 30 Nov 2023 00:00:00 GMT", "description": "This dataset comes from a ring shear device and is a series of values measured from the device including shear resistance as the fringe is growing", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Zoet, Lucas", "project_titles": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory", "projects": [{"proj_uid": "p0010434", "repository": "USAP-DC", "title": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Frozen fringe friction", "uid": "601756", "west": null}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": null, "date_created": "Wed, 30 Aug 2023 00:00:00 GMT", "description": "This dataset is the results of 3 experiments in which the spore-forming diatom Chaetoceros socialis was grown in culture and induced into resting spores by nitrate limitation. The nitrogen isotopic composition of accumulated biomass (\u03b415Nbiomass; \u2030 vs air) and of diatom-bound organic N (\u03b415Ndb; \u2030 vs air) are reported at two timepoints from each experiment: prior to and after resting spore formation. Experiments 1 and 2 provide measurements for CRS mixed with vegetative Chaetoceros cells, while Experiment 3 provides measurements for isolated CRS. Fluorescence and nitrate concentration was tracked throughout each experiment, with dissolved silica, ammonium, and total reduced nitrogen also measured in Experiment 3.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments", "uid": "601727", "west": null}, {"awards": "1543347 Rosenheim, Brad", "bounds_geometry": ["POINT(-149.59134 -84.640287)"], "date_created": "Mon, 13 Mar 2023 00:00:00 GMT", "description": "This dataset includes radiocarbon (\u00b9\u2074C) and stable carbon isotope (\u03b4\u00b9\u00b3C) data for a sediment core from Mercer Subglacial Lake. In addition, this dataset includes \u00b9\u2074C and \u03b4\u00b9\u00b3C for dissolved organic carbon, dissolved inorganic carbon, and particulate organic carbon from the Mercer Subglacial Lake water column. ", "east": -149.59134, "geometry": ["POINT(-149.59134 -84.640287)"], "keywords": "Antarctica; Isotope; Mercer Subglacial Lake; Radiocarbon; Subglacial Lake", "locations": "Mercer Subglacial Lake; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Venturelli, Ryan; Rosenheim, Brad", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Mercer Subglacial Lake radiocarbon and stable isotope data ", "uid": "601672", "west": -149.59134}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Fri, 03 Feb 2023 00:00:00 GMT", "description": "This dataset contains measurements of sediment porewater properties from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: specific conductance; water stable isotopes (\u03b42H and \u03b418O); dissolved gases (methane and its stable isotopes \u03b413C and \u03b42H, ethylene, and ethane); and major anions and cations.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Gas; Geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "locations": "Mercer Subglacial Lake; Mercer Subglacial Lake; West Antarctic Ice Sheet; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Michaud, Alexander; Skidmore, Mark; Tranter, Martyn; Steigmeyer, August; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "uid": "601664", "west": -149.50134}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Wed, 01 Feb 2023 00:00:00 GMT", "description": "This dataset contains bulk sediment properties measurements from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: physical properties (bulk density, mass water content, porosity, shear strength, particle size distribution, and mineralogy); carbon (inorganic and organic); iron (ascorbate- and dithionite-extractable); and sulfur (acid-volatile and chromium-reducible).", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; Physical Properties; SALSA; Sediment Core; Sulfur; West Antarctic Ice Sheet", "locations": "Antarctica; Mercer Subglacial Lake; West Antarctic Ice Sheet; Mercer Subglacial Lake", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "uid": "601661", "west": -149.50134}, {"awards": null, "bounds_geometry": null, "date_created": "Mon, 30 Jan 2023 00:00:00 GMT", "description": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "east": null, "geometry": null, "keywords": "Antarctica; Sediment Core Data", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "persons": "Liu, Xiaodong", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": null, "title": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "uid": "601660", "west": null}, {"awards": "2031442 Learman, Deric", "bounds_geometry": null, "date_created": "Thu, 08 Sep 2022 00:00:00 GMT", "description": "Shelf sediment samples were collected around the Antarctic Peninsular with the mega corer in 2020 (Nov. to Dec.). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set (10). ", "east": null, "geometry": null, "keywords": "Antarctica; Antarctic Peninsula; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "locations": "Weddell Sea; Antarctic Peninsula; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Learman, Deric", "project_titles": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "projects": [{"proj_uid": "p0010235", "repository": "USAP-DC", "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "uid": "601607", "west": null}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": ["POINT(-42.933 -61.849)"], "date_created": "Wed, 22 Jun 2022 00:00:00 GMT", "description": "This dataset contains measurements of major and trace elements on 190 samples of Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. The composition of detrital, biogenic and authigenic sediment components was assessed via whole rock geochemistry of sediment samples. Instrument analysis was completed at Montclair State University.", "east": -42.933, "geometry": ["POINT(-42.933 -61.849)"], "keywords": "Antarctica; Glaciation; IODP 650; IODP 696; Paleoceanography; Provenance; Sediment Core Data; Weathering; Weddell Sea", "locations": "Antarctica; Weddell Sea", "north": -61.849, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Hojnacki, Victoria; Li, Xiaona; States, Abbey; Lepp, Allison", "project_titles": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "projects": [{"proj_uid": "p0010101", "repository": "USAP-DC", "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.849, "title": "Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent", "uid": "601582", "west": -42.933}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": ["POINT(-42.933 -61.849)"], "date_created": "Tue, 21 Jun 2022 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Diatoms were generally either absent or present in trace amounts in the Eocene-Oligocene interval and were not removed. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive Index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": -42.933, "geometry": ["POINT(-42.933 -61.849)"], "keywords": "Antarctica; Glaciation; IODP 696; Marine Geoscience; Marine Sediments; Paleoceanography; Sediment Core Data; Weddell Sea", "locations": "Weddell Sea; Antarctica", "north": -61.849, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Lepp, Allison; Horowitz Castaldo, Josie; Light, Jennifer", "project_titles": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "projects": [{"proj_uid": "p0010101", "repository": "USAP-DC", "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.849, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent", "uid": "601581", "west": -42.933}, {"awards": "1341432 Brzezinski, Mark; 1341464 Robinson, Rebecca", "bounds_geometry": ["POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))"], "date_created": "Thu, 02 Jun 2022 00:00:00 GMT", "description": "This dataset contains data for particulate silicon, particulate carbon, particulate nitrogen, stable isotopes of nitrogen and stable isotopes of silicon in particulates from McLane pump profiles", "east": -165.0, "geometry": ["POINT(-170 -60.5)"], "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Diatom; Diatom Bound; Lithogenic Silica; Marine Geoscience; NBP1702; Nitrogen Isotopes; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "locations": "Southern Ocean; Antarctica; Southern Ocean", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Jones, Janice L.; Closset, Ivia; Robinson, Rebecca; Brzezinski, Mark", "project_titles": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "projects": [{"proj_uid": "p0010083", "repository": "USAP-DC", "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": " Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "uid": "601576", "west": -175.0}, {"awards": "1341432 Brzezinski, Mark", "bounds_geometry": ["POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))"], "date_created": "Mon, 16 May 2022 00:00:00 GMT", "description": "This dataset contains data for stable isotopes of silicon in pore water, interstitial water, sediments and CTD profiles.", "east": -165.0, "geometry": ["POINT(-170 -60.5)"], "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Lithogenic Silica; Marine Geoscience; NBP1702; Pore Water Biogeochemistry; Sediment; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "locations": "Southern Ocean; Antarctica", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Closset, Ivia; Jones, Janice L.; Brzezinski, Mark", "project_titles": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "projects": [{"proj_uid": "p0010083", "repository": "USAP-DC", "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Silicon concentration and isotopic composition measurements in seawater profiles, pore waters, interstitial waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "uid": "601562", "west": -175.0}, {"awards": "1644197 Simms, Alexander; 1643868 DeWitt, Regina", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "detailed results for rock and sediment OSL ages; De calculation; dose rate calculation, fading, signal measurement", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Antarctica; Livingston Island; Joinville Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Joinville and Livingston Islands - rock and sediment OSL ages", "uid": "601534", "west": -65.0}, {"awards": "1644197 Simms, Alexander; 1643868 DeWitt, Regina", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "sediment and rock samples were collected on Joinville and Livingston Islands for OSL dating; feldspar separates were prepared; data set includes Electron microprobe analysis of selected feldspar extracts; includes bmp and tif with elemental maps plus elemental concentrations and Ca:Na:K ratios for feldspar analysis", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Antarctica; Livingston Island; Joinville Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches", "uid": "601531", "west": -65.0}, {"awards": "1643868 DeWitt, Regina; 1644197 Simms, Alexander", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "raw OSL data for rock and sediment samples collected on Joinville and Livingston Islands", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Antarctica; Livingston Island; Joinville Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "OSL data - Joinville and Livingston Islands - Raw data", "uid": "601532", "west": -65.0}, {"awards": "1341464 Robinson, Rebecca", "bounds_geometry": ["POLYGON((-170.4 -60.8,-170.36 -60.8,-170.32 -60.8,-170.28 -60.8,-170.24 -60.8,-170.2 -60.8,-170.16 -60.8,-170.12 -60.8,-170.08 -60.8,-170.04 -60.8,-170 -60.8,-170 -61.34,-170 -61.88,-170 -62.42,-170 -62.96,-170 -63.5,-170 -64.04,-170 -64.58,-170 -65.12,-170 -65.66,-170 -66.2,-170.04 -66.2,-170.08 -66.2,-170.12 -66.2,-170.16 -66.2,-170.2 -66.2,-170.24 -66.2,-170.28 -66.2,-170.32 -66.2,-170.36 -66.2,-170.4 -66.2,-170.4 -65.66,-170.4 -65.12,-170.4 -64.58,-170.4 -64.04,-170.4 -63.5,-170.4 -62.96,-170.4 -62.42,-170.4 -61.88,-170.4 -61.34,-170.4 -60.8))"], "date_created": "Mon, 14 Feb 2022 00:00:00 GMT", "description": "Tracking variations in the surface ocean supply and demand of nitrate, a key marine nutrient, can help constrain the contribution of biological production in driving past climate shifts. The nitrogen isotopic composition (as \u03b415N) of organic matter in marine sediments is a proxy for surface ocean nitrate supply and demand over time but it may be subject to alteration during sinking and burial. The isotopic composition of nitrogen contained in the shells, or frustules, of diatoms (\u03b415NDB) is protected and is therefore a potentially more robust tracer of nitrate use in the past. Here we show that \u03b415NDB in Southern Ocean community cultures does not depend on species composition. We found the \u03b5DB (= biomass \u03b415N - \u03b415NDB) of the community growouts was -4.8 \u00b1 0.8\u2030, more than 10\u2030 different from previous monospecific growouts, but statistically indistinguishable from previous Southern Ocean and North Pacific surface ocean observations. The two community growouts, seeded with populations from 66\u00b0 and 61\u00b0S, had distinct community compositions but indistinguishable \u03b5DB, suggesting species composition does not primarily set \u03b415NDB values in the Southern Ocean. Our results demonstrate that under nitrate-replete conditions, \u03b415NDB values of frustules sinking from the surface ocean robustly track surface ocean nitrate \u03b415N values and therefore nitrate supply and demand. ", "east": -170.0, "geometry": ["POINT(-170.2 -63.5)"], "keywords": "Antarctica; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "locations": "Southern Ocean; Antarctica", "north": -60.8, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Jones, Colin; Robinson, Rebecca; Brzezinski, Mark; Riesselman, Christina; Closset, Ivia; Kelly, Roger; Robinson, Rebecca ", "project_titles": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "projects": [{"proj_uid": "p0010083", "repository": "USAP-DC", "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.2, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "uid": "601522", "west": -170.4}, {"awards": "1738942 Wellner, Julia", "bounds_geometry": ["POLYGON((-107.38 -74.64,-107.065 -74.64,-106.75 -74.64,-106.435 -74.64,-106.12 -74.64,-105.805 -74.64,-105.49 -74.64,-105.175 -74.64,-104.86 -74.64,-104.545 -74.64,-104.23 -74.64,-104.23 -74.683,-104.23 -74.726,-104.23 -74.769,-104.23 -74.812,-104.23 -74.855,-104.23 -74.898,-104.23 -74.941,-104.23 -74.984,-104.23 -75.027,-104.23 -75.07,-104.545 -75.07,-104.86 -75.07,-105.175 -75.07,-105.49 -75.07,-105.805 -75.07,-106.12 -75.07,-106.435 -75.07,-106.75 -75.07,-107.065 -75.07,-107.38 -75.07,-107.38 -75.027,-107.38 -74.984,-107.38 -74.941,-107.38 -74.898,-107.38 -74.855,-107.38 -74.812,-107.38 -74.769,-107.38 -74.726,-107.38 -74.683,-107.38 -74.64))"], "date_created": "Thu, 27 Jan 2022 00:00:00 GMT", "description": "This dataset contains measurements from grain-size, x-ray fluorescence (XRF), and physical properties (including magnetic susceptibility, water content, and shear strength) analyses of five sediment cores collected offshore Thwaites Glacier during cruises NBP19-02 (cores KC04, KC08, and KC23) and NBP20-02 (cores KC33 and KC67). We estimate the cores, which are between 213.5 and 297.5 cm in length, reflect deposition during the last ~10 kyr, consistent with published constraints of deglaciation of this region. Data are organized in Microsoft Excel spreadsheets and core locations are provided in a PDF.", "east": -104.23, "geometry": ["POINT(-105.805 -74.855)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Glaciomarine Sediment; Grain Size; Magnetic Susceptibility; Marine Geoscience; Marine Sediments; NBP1902; NBP2002; Physical Properties; R/v Nathaniel B. Palmer; Sediment Core Data; Thwaites Glacier; Trace Elements; XRF", "locations": "Thwaites Glacier; Antarctica", "north": -74.64, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Lepp, Allison", "project_titles": "NSF-NERC: THwaites Offshore Research (THOR)", "projects": [{"proj_uid": "p0010062", "repository": "USAP-DC", "title": "NSF-NERC: THwaites Offshore Research (THOR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.07, "title": "Physical and geochemical data from five sediment cores collected offshore Thwaites Glacier", "uid": "601514", "west": -107.38}, {"awards": "1826712 McMahon, Kelton; 1443585 Polito, Michael; 1443386 Emslie, Steven; 1443424 McMahon, Kelton", "bounds_geometry": ["POLYGON((-37.33 -54.05,-37.192 -54.05,-37.054 -54.05,-36.916 -54.05,-36.778 -54.05,-36.64 -54.05,-36.502 -54.05,-36.364 -54.05,-36.226 -54.05,-36.088 -54.05,-35.95 -54.05,-35.95 -54.107,-35.95 -54.164,-35.95 -54.221,-35.95 -54.278,-35.95 -54.335,-35.95 -54.392,-35.95 -54.449,-35.95 -54.506,-35.95 -54.563,-35.95 -54.62,-36.088 -54.62,-36.226 -54.62,-36.364 -54.62,-36.502 -54.62,-36.64 -54.62,-36.778 -54.62,-36.916 -54.62,-37.054 -54.62,-37.192 -54.62,-37.33 -54.62,-37.33 -54.563,-37.33 -54.506,-37.33 -54.449,-37.33 -54.392,-37.33 -54.335,-37.33 -54.278,-37.33 -54.221,-37.33 -54.164,-37.33 -54.107,-37.33 -54.05))"], "date_created": "Thu, 13 Jan 2022 00:00:00 GMT", "description": "This data set contains radiometric dating measurements from two aquatic sediment cores excavated from two separate sites (Salisbury Plain and Gold Harbor) on South Georgia Island in February 2019. It also contains biological and geochemical sediment proxy values from both sediment cores, including total carbon (%), total nitrogen (%), number of penguin feathers and eggshell fragments, number of seal hairs, and \u03b413C and \u03b415N stable isotope values. Cores were sectioned at 1cm intervals, and radiometric dating analyses were conducted on sediment fractions \u003c850 \u00b5m by measuring for 210Pb and 226Ra (via 214Pb) by direct gamma counting using the high purity germanium planar detector in the Marine Geochemistry Laboratory at Louisiana State University (LSU). The 210Pbex profiles were used to calculate sedimentation rates using a steady state model that assumes constant rate of supply and constant sedimentation rate (Maiti et al., 2010). Geochemical analyses were performed on sediment fractions \u003c125 \u00b5m using an Elemental Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS) in the Stable Isotope Ecology Lab at LSU. Biological counts of feathers and hairs were determined by enumeration using a dissecting microscope of sediment fractions \u003e1000 \u00b5m. The data set also includes sediment core excavation site names and coordinates, date of excavation, sediment depth and age, and carbon to nitrogen isotopic ratios. Details of the data set and all relevant methods are provided in Kristan et al., 2021.", "east": -35.95, "geometry": ["POINT(-36.64 -54.335)"], "keywords": "Antarctica; Antarctic Fur Seal; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "locations": "Antarctica; South Georgia Island; Sub-Antarctic; South Atlantic Ocean", "north": -54.05, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Kristan, Allyson; Maiti, Kanchan; McMahon, Kelton; Polito, Michael", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -54.62, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "uid": "601509", "west": -37.33}, {"awards": "1433140 Domack, Eugene; 0732625 Leventer, Amy", "bounds_geometry": ["POLYGON((-69 -58,-67.7 -58,-66.4 -58,-65.1 -58,-63.8 -58,-62.5 -58,-61.2 -58,-59.9 -58,-58.6 -58,-57.3 -58,-56 -58,-56 -59,-56 -60,-56 -61,-56 -62,-56 -63,-56 -64,-56 -65,-56 -66,-56 -67,-56 -68,-57.3 -68,-58.6 -68,-59.9 -68,-61.2 -68,-62.5 -68,-63.8 -68,-65.1 -68,-66.4 -68,-67.7 -68,-69 -68,-69 -67,-69 -66,-69 -65,-69 -64,-69 -63,-69 -62,-69 -61,-69 -60,-69 -59,-69 -58))"], "date_created": "Mon, 15 Nov 2021 00:00:00 GMT", "description": "This data set contains an age vs depth model and measurements of magnetic susceptibility, benthic foraminifera Bulimina aculeata d18O and d13C, bulk sediment GDGT data, and diatom assemblage data from USAP LMG13-11 JKC-1 sediment core (0-100 cm) archived at the Oregon State University ACC repository. All stable isotope and GDGT measurements were made at the University of South Florida College of Marine Science. Diatom assemblages were counted at Colgate University. The data set includes all replicate measurements. Details of the entire data set and all relevant methods are provided in Browne et al (submitted, 2021)", "east": -56.0, "geometry": ["POINT(-62.5 -63)"], "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "locations": "Antarctic Peninsula; Antarctica", "north": -58.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "persons": "Shevenell, Amelia", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "projects": [{"proj_uid": "p0000101", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "LMG13-11 JKC-1 Paleoceanographic data", "uid": "601485", "west": -69.0}, {"awards": "0440775 Jacobs, Stanley", "bounds_geometry": ["POLYGON((-180 -71.12,-172.34 -71.12,-164.68 -71.12,-157.02 -71.12,-149.36 -71.12,-141.7 -71.12,-134.04 -71.12,-126.38 -71.12,-118.72 -71.12,-111.06 -71.12,-103.4 -71.12,-103.4 -71.833,-103.4 -72.546,-103.4 -73.259,-103.4 -73.972,-103.4 -74.685,-103.4 -75.398,-103.4 -76.111,-103.4 -76.824,-103.4 -77.537,-103.4 -78.25,-111.06 -78.25,-118.72 -78.25,-126.38 -78.25,-134.04 -78.25,-141.7 -78.25,-149.36 -78.25,-157.02 -78.25,-164.68 -78.25,-172.34 -78.25,180 -78.25,178.657 -78.25,177.314 -78.25,175.971 -78.25,174.628 -78.25,173.285 -78.25,171.942 -78.25,170.599 -78.25,169.256 -78.25,167.913 -78.25,166.57 -78.25,166.57 -77.537,166.57 -76.824,166.57 -76.111,166.57 -75.398,166.57 -74.685,166.57 -73.972,166.57 -73.259,166.57 -72.546,166.57 -71.833,166.57 -71.12,167.913 -71.12,169.256 -71.12,170.599 -71.12,171.942 -71.12,173.285 -71.12,174.628 -71.12,175.971 -71.12,177.314 -71.12,178.657 -71.12,-180 -71.12))"], "date_created": "Fri, 17 Sep 2021 00:00:00 GMT", "description": "This dataset contains images and field description of Smith-McIntyre sediment grab samples from Expedition NBP0702 between the Ross Sea and the Amundsen Sea. ", "east": -103.4, "geometry": ["POINT(-148.415 -74.685)"], "keywords": "Amundsen Sea; Antarctica; Marine Geoscience; Marine Sediments; NBP0702; Photo; R/v Nathaniel B. Palmer; Seafloor Sampling; Sediment Description; Smith-Mcintyre Grab", "locations": "Amundsen Sea; Amundsen Sea; Antarctica", "north": -71.12, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Leventer, Amy; Jacobs, Stanley", "project_titles": "The Amundsen Continental Shelf and the Antarctic Ice Sheet", "projects": [{"proj_uid": "p0000836", "repository": "USAP-DC", "title": "The Amundsen Continental Shelf and the Antarctic Ice Sheet"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.25, "title": "NBP0702 surface sediment sample information and images", "uid": "601473", "west": 166.57}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(74.787 -67.696167)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene sediment from Ocean Drilling Program Site 1166 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 74.787, "geometry": ["POINT(74.787 -67.696167)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP1166; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.696167, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.696167, "title": "Particle-size distributions of Eocene sediment from ODP Site 1166, Prydz Bay", "uid": "601455", "west": 74.787}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(75.4045 -67.549667)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 742 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 75.4045, "geometry": ["POINT(75.4045 -67.549667)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP742; Oligocene; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.549667, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.549667, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 742, Prydz Bay", "uid": "601454", "west": 75.4045}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(75.081833 -67.276167)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 739 in Prydz Bay. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 75.081833, "geometry": ["POINT(75.081833 -67.276167)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP739; Oligocene; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.276167, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.276167, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 739, Prydz Bay", "uid": "601453", "west": 75.081833}, {"awards": "0838842 Passchier, Sandra", "bounds_geometry": ["POINT(167.0833 -77.8889)"], "date_created": "Mon, 14 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of particle-size distributions on four intervals of diamicitites from ANDRILL Site AND-2A. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2 and 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 167.0833, "geometry": ["POINT(167.0833 -77.8889)"], "keywords": "Antarctica; McMurdo Sound; Miocene; Particle Size; Pleistocene; Pliocene", "locations": "Antarctica; McMurdo Sound", "north": -77.8889, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Hansen, Melissa A.", "project_titles": "Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples", "projects": [{"proj_uid": "p0000147", "repository": "USAP-DC", "title": "Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.8889, "title": "Particle-size measurements for diamictites AND-2A sediment core, McMurdo Sound", "uid": "601452", "west": 167.0833}, {"awards": "0342484 Harwood, David", "bounds_geometry": ["POINT(167 -78)"], "date_created": "Mon, 14 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of particle-size distributions on sediment from ANDRILL Site AND-2A. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2 and 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 167.0, "geometry": ["POINT(167 -78)"], "keywords": "Andrill; Antarctica; Continental Shelf; Diamict; McMurdo Sound; Miocene; Paleoclimate; Particle Size", "locations": "McMurdo Sound; Antarctica", "north": -78.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Candice, Falk", "project_titles": "Collaborative Research: ANDRILL - - Investigating Antarcticas Role in Cenozoic Global Environmental Change", "projects": [{"proj_uid": "p0010297", "repository": "USAP-DC", "title": "Collaborative Research: ANDRILL - - Investigating Antarcticas Role in Cenozoic Global Environmental Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -78.0, "title": "Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound", "uid": "601451", "west": 167.0}, {"awards": "1060080 TBD", "bounds_geometry": ["POINT(144 -65)"], "date_created": "Mon, 14 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Pliocene sediment from Integrated Ocean Drilling Program Site U1359 on the Wilkes Land margin. Biogenic silica, carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate, and after supernatant was removed, digestion in 0.2 N NaOH at ~85 degrees for 1 hour. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 144.0, "geometry": ["POINT(144 -65)"], "keywords": "Antarctica; Ice-Rafting; Marine Geoscience; Paleoclimate; Particle Size; Sediment Core Data; Wilkes Land", "locations": "Wilkes Land; Antarctica", "north": -65.0, "nsf_funding_programs": null, "persons": "Passchier, Sandra; Hansen, Melissa A.; Rosenberg, Jessica", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -65.0, "title": "Particle-size distributions of Pliocene sediment from IODP Site U1359", "uid": "601450", "west": 144.0}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.1,121 -66.2,121 -66.3,121 -66.4,121 -66.5,121 -66.6,121 -66.7,121 -66.8,121 -66.9,121 -67,120.9 -67,120.8 -67,120.7 -67,120.6 -67,120.5 -67,120.4 -67,120.3 -67,120.2 -67,120.1 -67,120 -67,120 -66.9,120 -66.8,120 -66.7,120 -66.6,120 -66.5,120 -66.4,120 -66.3,120 -66.2,120 -66.1,120 -66))"], "date_created": "Tue, 27 Apr 2021 00:00:00 GMT", "description": "This dataset includes diatom data, both absolute abundance and relative contribution, for NBP1402 JPC43. ", "east": 121.0, "geometry": ["POINT(120.5 -66.5)"], "keywords": "Antarctica; Diatom; Holocene; Jumbo Piston Corer; NBP1402; R/v Nathaniel B. Palmer; Sabrina Coast; Sediment Core Data; Species Abundance; Totten Glacier", "locations": "Antarctica; Sabrina Coast; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "NBP1402 JPC43 Diatom Data", "uid": "601440", "west": 120.0}, {"awards": "1724670 Williams, Trevor", "bounds_geometry": ["POLYGON((-65 -74,-61 -74,-57 -74,-53 -74,-49 -74,-45 -74,-41 -74,-37 -74,-33 -74,-29 -74,-25 -74,-25 -74.6,-25 -75.2,-25 -75.8,-25 -76.4,-25 -77,-25 -77.6,-25 -78.2,-25 -78.8,-25 -79.4,-25 -80,-29 -80,-33 -80,-37 -80,-41 -80,-45 -80,-49 -80,-53 -80,-57 -80,-61 -80,-65 -80,-65 -79.4,-65 -78.8,-65 -78.2,-65 -77.6,-65 -77,-65 -76.4,-65 -75.8,-65 -75.2,-65 -74.6,-65 -74))"], "date_created": "Mon, 05 Oct 2020 00:00:00 GMT", "description": "This dataset contains 40Ar/39Ar measurements on detrital mineral grains from subglacial till and proximal glacimarine sediment from nine sediment cores along the front of the Filchner and Ronne Ice Shelves. ", "east": -25.0, "geometry": ["POINT(-45 -77)"], "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Sediments; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "locations": "Antarctica; Weddell Sea", "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Williams, Trevor", "project_titles": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance", "projects": [{"proj_uid": "p0010128", "repository": "USAP-DC", "title": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "uid": "601378", "west": -65.0}, {"awards": "1724670 Williams, Trevor", "bounds_geometry": ["POLYGON((-70 -80,-65 -80,-60 -80,-55 -80,-50 -80,-45 -80,-40 -80,-35 -80,-30 -80,-25 -80,-20 -80,-20 -80.6,-20 -81.2,-20 -81.8,-20 -82.4,-20 -83,-20 -83.6,-20 -84.2,-20 -84.8,-20 -85.4,-20 -86,-25 -86,-30 -86,-35 -86,-40 -86,-45 -86,-50 -86,-55 -86,-60 -86,-65 -86,-70 -86,-70 -85.4,-70 -84.8,-70 -84.2,-70 -83.6,-70 -83,-70 -82.4,-70 -81.8,-70 -81.2,-70 -80.6,-70 -80))"], "date_created": "Mon, 05 Oct 2020 00:00:00 GMT", "description": "This dataset contains 40Ar/39Ar measurements on detrital mineral grains from till in modern moraines at the edges of the Institute, Foundation, Academy, Recovery, and the Slessor glaciers / ice streams.", "east": -20.0, "geometry": ["POINT(-45 -83)"], "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Sediments; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "locations": "Weddell Sea; Antarctica", "north": -80.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Williams, Trevor", "project_titles": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance", "projects": [{"proj_uid": "p0010128", "repository": "USAP-DC", "title": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "uid": "601377", "west": -70.0}, {"awards": "1724670 Williams, Trevor", "bounds_geometry": ["POLYGON((-50 -62,-49 -62,-48 -62,-47 -62,-46 -62,-45 -62,-44 -62,-43 -62,-42 -62,-41 -62,-40 -62,-40 -62.3,-40 -62.6,-40 -62.9,-40 -63.2,-40 -63.5,-40 -63.8,-40 -64.1,-40 -64.4,-40 -64.7,-40 -65,-41 -65,-42 -65,-43 -65,-44 -65,-45 -65,-46 -65,-47 -65,-48 -65,-49 -65,-50 -65,-50 -64.7,-50 -64.4,-50 -64.1,-50 -63.8,-50 -63.5,-50 -63.2,-50 -62.9,-50 -62.6,-50 -62.3,-50 -62))"], "date_created": "Mon, 05 Oct 2020 00:00:00 GMT", "description": "This dataset contains 40Ar/39Ar measurements on detrital mineral grains from ice-rafted detritus from sediment core PS1575-1 in the NW Weddell Sea. The depositional age of the sediments is approx. 0 to 300 ka. ", "east": -40.0, "geometry": ["POINT(-45 -63.5)"], "keywords": "40Ar/39Ar Thermochronology; Antarctica; Argon; Chemistry:sediment; Chemistry:Sediment; Detrital Minerals; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; Mass Spectrometer; Provenance; R/v Polarstern; Sediment Core Data; Subglacial Till; Till; Weddell Sea", "locations": "Weddell Sea; Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Williams, Trevor", "project_titles": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance", "projects": [{"proj_uid": "p0010128", "repository": "USAP-DC", "title": "Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment", "uid": "601379", "west": -50.0}, {"awards": "1644187 Tulaczyk, Slawek", "bounds_geometry": ["POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9))"], "date_created": "Sat, 12 Sep 2020 00:00:00 GMT", "description": " The ANTAEM survey was carried out in the period November 12th to 28th, 2018, with the SkyTEM 312 system. Twenty-one missions (flights) were conducted over 11 production days of helicopter service, resulting in a total of approximately ~3400 line km of data. The SkyTEM system records data from take-off until landing resulting in multiple lines converging to the landing pads in McMurdo and at Marble Point. The production without overlapping lines adds up to approximately 2900 line km. The flight speed was approximately 120 km/h at a target flight altitude of ~50 m (sensor height), but the actual sensor height varies depending on the terrain. The surveys were carried out with a Bell 212 helicopter, which carried the SkyTEM sensor as a sling load. The SkyTEM system was configured in a standard two-moment setup (low moment, LM and high moment, HM). Areas with extremely resistive dry and/or frozen sediment/bedrock, and glacier ice often produce EM-signals with amplitudes below the detection level of the system. Data from these low signal environments cannot be inverted into resistivity models. Data with strong induced polarization effects cannot be inverted for resistivity either. These data were discharged in this standard data delivery. \r\n The EM-data and inversion result (resistivity models) are delivered in the SkyTEM2018_dat.xyz and SkyTEM2018_inv.xyz files respectably. The RECORD number in the two files links data and model together. EM-data and data uncertainty for data entering inversion. Info stated in file Header: NAN value, Data unit, Coordinate system, Gate times. The SkyTEM system uses at High-Low moment data recording cycle, therefore only a subset of the total 40 time gates are preset for each moment. The standard lateral constraints inversion (LCI), delivered in the SkyTEM2018_inv.xyz file, was carried out with a smooth 30 layered resistivity model discretized to a depth of 500 m. A depth of investigation (DOI) was estimated for each resistivity model.\r\n", "east": 168.5, "geometry": ["POINT(164.75 -77.6)"], "keywords": "Antarctica; Dry Valleys; Hydrology; Ice Shelf; McMurdo; Permafrost", "locations": "Dry Valleys; McMurdo; Antarctica", "north": -76.9, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Tulaczyk, Slawek", "project_titles": "Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica", "projects": [{"proj_uid": "p0010129", "repository": "USAP-DC", "title": "Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.3, "title": "ANTAEM project airborne EM resistivity data from McMurdo Region", "uid": "601373", "west": 161.0}, {"awards": "0338137 Anderson, John", "bounds_geometry": ["POLYGON((-76 -45.5,-75.2 -45.5,-74.4 -45.5,-73.6 -45.5,-72.8 -45.5,-72 -45.5,-71.2 -45.5,-70.4 -45.5,-69.6 -45.5,-68.8 -45.5,-68 -45.5,-68 -46.43,-68 -47.36,-68 -48.29,-68 -49.22,-68 -50.15,-68 -51.08,-68 -52.01,-68 -52.94,-68 -53.87,-68 -54.8,-68.8 -54.8,-69.6 -54.8,-70.4 -54.8,-71.2 -54.8,-72 -54.8,-72.8 -54.8,-73.6 -54.8,-74.4 -54.8,-75.2 -54.8,-76 -54.8,-76 -53.87,-76 -52.94,-76 -52.01,-76 -51.08,-76 -50.15,-76 -49.22,-76 -48.29,-76 -47.36,-76 -46.43,-76 -45.5))"], "date_created": "Fri, 17 Jul 2020 00:00:00 GMT", "description": "Excel file with station names, location and water depth and description of the coring device for NBP0505.", "east": -68.0, "geometry": ["POINT(-72 -50.15)"], "keywords": "Chile; Fjord; Marine Geoscience; NBP0505; R/v Nathaniel B. Palmer; Sample/collection Description; Sample/Collection Description; Sediment Core; Sediment Corer; Station List", "locations": "Chile; Chile", "north": -45.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Wellner, Julia; Anderson, John", "project_titles": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica", "projects": [{"proj_uid": "p0000821", "repository": "USAP-DC", "title": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -54.8, "title": "NBP0505 sediment core locations", "uid": "601362", "west": -76.0}, {"awards": "0338137 Anderson, John", "bounds_geometry": ["POLYGON((-76 -45.5,-75.2 -45.5,-74.4 -45.5,-73.6 -45.5,-72.8 -45.5,-72 -45.5,-71.2 -45.5,-70.4 -45.5,-69.6 -45.5,-68.8 -45.5,-68 -45.5,-68 -46.43,-68 -47.36,-68 -48.29,-68 -49.22,-68 -50.15,-68 -51.08,-68 -52.01,-68 -52.94,-68 -53.87,-68 -54.8,-68.8 -54.8,-69.6 -54.8,-70.4 -54.8,-71.2 -54.8,-72 -54.8,-72.8 -54.8,-73.6 -54.8,-74.4 -54.8,-75.2 -54.8,-76 -54.8,-76 -53.87,-76 -52.94,-76 -52.01,-76 -51.08,-76 -50.15,-76 -49.22,-76 -48.29,-76 -47.36,-76 -46.43,-76 -45.5))"], "date_created": "Fri, 17 Jul 2020 00:00:00 GMT", "description": "Raw CTD data from expedition NBP0505 collected with the Aanderaa and Seacat CTD systems", "east": -68.0, "geometry": ["POINT(-72 -50.15)"], "keywords": "Chile; CTD; CTD Data; Depth; Fjord; NBP0505; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "locations": "Chile", "north": -45.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Wellner, Julia; Anderson, John", "project_titles": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica", "projects": [{"proj_uid": "p0000821", "repository": "USAP-DC", "title": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -54.8, "title": "NBP0505 CTD data", "uid": "601363", "west": -76.0}, {"awards": null, "bounds_geometry": ["POINT(-163.61187 -84.33543)"], "date_created": "Wed, 15 Jul 2020 00:00:00 GMT", "description": "This dataset contains total organic carbon (%TOC) and carbon isotopic data (\u03b4\u00b9\u00b3C, \u0394\u00b9\u2074C) from sediments retrieved from the Whillans Ice Stream grounding zone during the 2015 Antarctic field season. All %TOC and sediment preparations were done at the University of South Florida. Radiocarbon measurements were done at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) laboratory. ", "east": -163.61187, "geometry": ["POINT(-163.61187 -84.33543)"], "keywords": "Antarctica; Radiocarbon; Sediment; Whillans Ice Stream", "locations": "Whillans Ice Stream; Antarctica", "north": -84.33543, "nsf_funding_programs": null, "persons": "Venturelli, Ryan A", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WISSARD", "south": -84.33543, "title": "Isotopic data from Whillans Ice Stream grounding zone, West Antarctica", "uid": "601360", "west": -163.61187}, {"awards": "1341669 DeMaster, David; 0732711 Smith, Craig", "bounds_geometry": ["POLYGON((-61 -64,-60.5 -64,-60 -64,-59.5 -64,-59 -64,-58.5 -64,-58 -64,-57.5 -64,-57 -64,-56.5 -64,-56 -64,-56 -64.1,-56 -64.2,-56 -64.3,-56 -64.4,-56 -64.5,-56 -64.6,-56 -64.7,-56 -64.8,-56 -64.9,-56 -65,-56.5 -65,-57 -65,-57.5 -65,-58 -65,-58.5 -65,-59 -65,-59.5 -65,-60 -65,-60.5 -65,-61 -65,-61 -64.9,-61 -64.8,-61 -64.7,-61 -64.6,-61 -64.5,-61 -64.4,-61 -64.3,-61 -64.2,-61 -64.1,-61 -64))"], "date_created": "Fri, 19 Jun 2020 00:00:00 GMT", "description": "This file contains Pb-210 data from bulk sediments beneath the collapsed Larsen A Ice Shelf and C-14 data from the organic fraction of the same samples.", "east": -56.0, "geometry": ["POINT(-58.5 -64.5)"], "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "locations": "Larsen Ice Shelf; Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "persons": "DeMaster, David; Taylor, Richard", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans; Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "projects": [{"proj_uid": "p0000101", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans"}, {"proj_uid": "p0000382", "repository": "USAP-DC", "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -65.0, "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "uid": "601336", "west": -61.0}, {"awards": "0636773 DeMaster, David; 1341669 DeMaster, David", "bounds_geometry": ["POLYGON((-71 -64,-70.4 -64,-69.8 -64,-69.2 -64,-68.6 -64,-68 -64,-67.4 -64,-66.8 -64,-66.2 -64,-65.6 -64,-65 -64,-65 -64.7,-65 -65.4,-65 -66.1,-65 -66.8,-65 -67.5,-65 -68.2,-65 -68.9,-65 -69.6,-65 -70.3,-65 -71,-65.6 -71,-66.2 -71,-66.8 -71,-67.4 -71,-68 -71,-68.6 -71,-69.2 -71,-69.8 -71,-70.4 -71,-71 -71,-71 -70.3,-71 -69.6,-71 -68.9,-71 -68.2,-71 -67.5,-71 -66.8,-71 -66.1,-71 -65.4,-71 -64.7,-71 -64))"], "date_created": "Mon, 11 May 2020 00:00:00 GMT", "description": "This data set is used to describe a new technique for assessing labile organic carbon (LOC) abundances and mean residence times in marine sediments. Radiocarbon is used to determine abundances of labile organic carbon and then a diagenetic organic carbon model, coupled with sediment biotrubation coefficients, is used to assess LOC mean residence times. ", "east": -65.0, "geometry": ["POINT(-68 -67.5)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon; LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "locations": "Antarctic Peninsula; Marguerite Bay; Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "persons": "DeMaster, David; Taylor, Richard; Smith, Craig; Isla, Enrique; Thomas, Carrie", "project_titles": "Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling; Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "projects": [{"proj_uid": "p0000552", "repository": "USAP-DC", "title": "Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling"}, {"proj_uid": "p0000382", "repository": "USAP-DC", "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -71.0, "title": "Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf", "uid": "601319", "west": -71.0}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": ["POINT(62.99 -67.13)"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "This data set was acquired with a Jumbo Piston Core Sediment Sampler during R/V Nathaniel B. Palmer expedition NBP0101 conducted in 2001. This data file is of Microsoft Excel format and includes Quantitative Diatom Assemblage data; counts completed on randomly settled slides (Scherer, R.P., 1994. A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles. Journal of Paleolimnology, 12 (1), 171-178, doi:10.1007/BF00678093). These counts were completed at closely spaced intervals in NBP0101 JPC41, a jumbo piston core from Iceberg Alley, Mac.Robertson Shelf, East Antarctica", "east": 62.99, "geometry": ["POINT(62.99 -67.13)"], "keywords": "Antarctica; Biota; Diatom; East Antarctica; Mac. Robertson Shelf; Marine Geoscience; Microscope; NBP0101; Paleoclimate; Piston Corer; R/v Nathaniel B. Palmer; Sediment Core; Species Abundance", "locations": "Mac. Robertson Shelf; Antarctica; East Antarctica; Mac. Robertson Shelf", "north": -67.13, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Leventer, Amy", "project_titles": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "projects": [{"proj_uid": "p0000609", "repository": "USAP-DC", "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.13, "title": "Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "uid": "601307", "west": 62.99}, {"awards": "0732711 Smith, Craig; 1341669 DeMaster, David", "bounds_geometry": ["POLYGON((-61 -62,-60.4 -62,-59.8 -62,-59.2 -62,-58.6 -62,-58 -62,-57.4 -62,-56.8 -62,-56.2 -62,-55.6 -62,-55 -62,-55 -62.34,-55 -62.68,-55 -63.02,-55 -63.36,-55 -63.7,-55 -64.04,-55 -64.38,-55 -64.72,-55 -65.06,-55 -65.4,-55.6 -65.4,-56.2 -65.4,-56.8 -65.4,-57.4 -65.4,-58 -65.4,-58.6 -65.4,-59.2 -65.4,-59.8 -65.4,-60.4 -65.4,-61 -65.4,-61 -65.06,-61 -64.72,-61 -64.38,-61 -64.04,-61 -63.7,-61 -63.36,-61 -63.02,-61 -62.68,-61 -62.34,-61 -62))"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203. Data were acquired as part of the project(s): Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems (LARISSA); and Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change.", "east": -55.0, "geometry": ["POINT(-58 -63.7)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1203; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "locations": "Antarctica; Antarctic Peninsula; Larsen Ice Shelf", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences", "persons": "Smith, Craig", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems.; Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "projects": [{"proj_uid": "p0010135", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems."}, {"proj_uid": "p0000382", "repository": "USAP-DC", "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -65.4, "title": "Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "uid": "601304", "west": -61.0}, {"awards": "0636806 Smith, Craig; 0636773 DeMaster, David", "bounds_geometry": ["POLYGON((-72 -59,-71 -59,-70 -59,-69 -59,-68 -59,-67 -59,-66 -59,-65 -59,-64 -59,-63 -59,-62 -59,-62 -59.95,-62 -60.9,-62 -61.85,-62 -62.8,-62 -63.75,-62 -64.7,-62 -65.65,-62 -66.6,-62 -67.55,-62 -68.5,-63 -68.5,-64 -68.5,-65 -68.5,-66 -68.5,-67 -68.5,-68 -68.5,-69 -68.5,-70 -68.5,-71 -68.5,-72 -68.5,-72 -67.55,-72 -66.6,-72 -65.65,-72 -64.7,-72 -63.75,-72 -62.8,-72 -61.85,-72 -60.9,-72 -59.95,-72 -59))"], "date_created": "Thu, 30 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Box Core Sediment Sampler, Digital Camera, and Sediment Core Sampler during Laurence M. Gould expedition LMG0802 conducted in 2008. The data files are in Microsoft Excel format and include Species List, Species Abundance, and Sediment Geochemistry data that was processed after collection.", "east": -62.0, "geometry": ["POINT(-67 -63.75)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; Chlorophyll Concentration; LMG0802; Marcofauna; Megafauna; Oceans; R/v Laurence M. Gould; Seafloor Sampling; Species Abundance", "locations": "Antarctica; Antarctic Peninsula", "north": -59.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences", "persons": "Smith, Craig; DeMaster, David", "project_titles": "Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling", "projects": [{"proj_uid": "p0000552", "repository": "USAP-DC", "title": "Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -68.5, "title": "Species List, Species Abundance, and Sediment Geochemistry processed data acquired during Laurence M. Gould expedition LMG0802", "uid": "601303", "west": -72.0}, {"awards": "1443680 Smith, Craig", "bounds_geometry": ["POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64))"], "date_created": "Tue, 31 Dec 2019 00:00:00 GMT", "description": "Sediment macrofaunal data collected by megacore (10-cm diameter sample tubes) along a down-fjord transect from inner Andvord Bay out onto the open continental shelf on the West Antarctic Peninsula. Sediment core samples from 0 - 10 cm depths were fixed in 4% formaldehyde, sieved on a 300 micron seive, and sorted with a dissecting microscope. ", "east": -62.0, "geometry": ["POINT(-64 -64.5)"], "keywords": "Abundance; Andvord Bay; Antarctica; Antarctic Peninsula; Biota; Fjord; LMG1510; Marine Sediments; Oceans; Polychaete; Polychaete Family Richness; R/v Laurence M. Gould; Sediment Core Data; Sediment Macrofauna", "locations": "Andvord Bay; Antarctica; Antarctic Peninsula", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Smith, Craig", "project_titles": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "projects": [{"proj_uid": "p0010010", "repository": "USAP-DC", "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "FjordEco", "south": -65.0, "title": "Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf", "uid": "601236", "west": -66.0}, {"awards": "0839059 Powell, Ross", "bounds_geometry": ["POLYGON((-180 -80,-174 -80,-168 -80,-162 -80,-156 -80,-150 -80,-144 -80,-138 -80,-132 -80,-126 -80,-120 -80,-120 -80.5,-120 -81,-120 -81.5,-120 -82,-120 -82.5,-120 -83,-120 -83.5,-120 -84,-120 -84.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -84.5,180 -84,180 -83.5,180 -83,180 -82.5,180 -82,180 -81.5,180 -81,180 -80.5,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,-180 -80))"], "date_created": "Thu, 19 Dec 2019 00:00:00 GMT", "description": "This data set includes biomarker data presented in Paleogene marine and terrestrial development of the West Antarctic Rift System. Included in the alkane sheet are the Terrestrial/aquatic (T/A) n-alkane ratio, total long (C27-C33)- and mid-chain (C23 and C25) n-alkane concentrations in units of ng alkanes per g sediment extracted, and the n-alkane average chain-length (ACL). Included in the glycerol dialkyl glycerol tetraethers (GDGT) sheet are the TEX86 sea surface temperature estimates with multiple calibrations discussed in the text, the MBT\u20195ME mean annual air temperature estimates, the branched and isoprenoid tetraether (BIT) index. ", "east": -120.0, "geometry": ["POINT(-150 -82.5)"], "keywords": "ACL; Antarctica; Biomarker; BIT Index; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Stream; Whillans Ice Stream; WISSARD", "locations": "Antarctica; Whillans Ice Stream", "north": -80.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Coenen, Jason; Casta\u00f1eda, Isla; Warny, Sophie; Baudoin, Patrick; Scherer, Reed Paul; Askin, Rosemary", "project_titles": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "projects": [{"proj_uid": "p0000105", "repository": "USAP-DC", "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WISSARD", "south": -85.0, "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set", "uid": "601234", "west": 180.0}, {"awards": "1443420 Dodd, Justin", "bounds_geometry": ["POINT(167.083333 -77.888889)"], "date_created": "Sun, 27 Oct 2019 00:00:00 GMT", "description": "The Andrill-1B (AND-1B) sediment core from under the Ross Ice Shelf in McMurdo Sound, Antarctica, recovered a mid to late Pliocene (~4.68 to 3.44 Ma) age diatomite unit with d18Odiatom values that range from +32.6 to +37.6 \u2030 (n=50 ", "east": 167.083333, "geometry": ["POINT(167.083333 -77.888889)"], "keywords": "And-1B; Andrill; Antarctica; Chemistry:sediment; Chemistry:Sediment; Delta 18O; Diatom; Mass Spectrometer; Oxygen Isotope; Paleoclimate; Pliocene; Sediment; Wais Project; West Antarctic Ice Sheet", "locations": "West Antarctic Ice Sheet; Antarctica", "north": -77.888889, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dodd, Justin; Abbott, Tirzah", "project_titles": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "projects": [{"proj_uid": "p0010042", "repository": "USAP-DC", "title": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.888889, "title": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "uid": "601220", "west": 167.083333}, {"awards": "0732625 Leventer, Amy; 9714371 Leventer, Amy", "bounds_geometry": ["POLYGON((-64 -63,-63.1 -63,-62.2 -63,-61.3 -63,-60.4 -63,-59.5 -63,-58.6 -63,-57.7 -63,-56.8 -63,-55.9 -63,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-55 -65.4,-55 -65.8,-55 -66.2,-55 -66.6,-55 -67,-55.9 -67,-56.8 -67,-57.7 -67,-58.6 -67,-59.5 -67,-60.4 -67,-61.3 -67,-62.2 -67,-63.1 -67,-64 -67,-64 -66.6,-64 -66.2,-64 -65.8,-64 -65.4,-64 -65,-64 -64.6,-64 -64.2,-64 -63.8,-64 -63.4,-64 -63))"], "date_created": "Mon, 16 Sep 2019 00:00:00 GMT", "description": "Diatom data from eastern side of Antarctic Peninsula:\r\n\r\nThis file includes quantitative diatom data for surface samples collected on numerous cruises to the eastern side of the Antarctic Peninsula, including NBP0003, NBP0107, LMG0502, NBP0603, and NBP1203. Samples were collected using a variety of tools including Smith-McIntyre Grab, Kasten Core and Jumbo Kasten Core. These data were generated by Amy Leventer (aleventer@colgate.edu) and undergraduate students at Colgate University. All questions regarding the specifics of these data should be directed to Amy Leventer. \r\n\r\nQuantitative diatom slides were prepared according to the settling technique of Scherer (1995). Cover slips were adhered to the slides using Norland Optical Adhesive #61. Slides were observed under Olympus CX31, BX50 and BX60, and Zeiss Primo Star light microscopes, using a 100X oil immersion objective for a total magnification of 1000X. A minimum of 400 valves or 10 transects was counted for each slide, depending on the absolute diatom abundance. Valves were only counted if \u003e50% complete. Diatoms were identified to species level when possible (Crosta et al., 2005; Armand et al., 2005; Cefarelli et al., 2010).\r\n\r\nArmand, L.K., X. Crosta, O. Romero, J. J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species, Paleogeography, Paleoclimatology, Paleoecology, 223, 93-126. \r\n\r\nCefarelli, A.O., M. E. Ferrario, G. O. Almandoz, A. G. Atencio, R. Akselman, M. Vernet (2010), Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance, Polar Biology, 33(2), 1463-1484. \r\n\r\nCrosta, X., O. Romero, L. K. Armand, J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species, Palaeogeography, Palaeoclimatology, Palaeoecology, 223, 66-92. \r\n\r\nScherer, R. P., A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles, J. Paleolimnol., 12, 171\u2013178, 1995.\r\n", "east": -55.0, "geometry": ["POINT(-59.5 -65)"], "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biota; Diatom; Geology/Geophysics - Other; LMG0502; Marine Geoscience; Marine Sediments; Microscope; NBP0003; NBP0107; NBP0603; NBP1203; R/v Nathaniel B. Palmer; Surface Sediment", "locations": "Antarctica; Antarctic Peninsula", "north": -63.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "persons": "Leventer, Amy", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "projects": [{"proj_uid": "p0000101", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -67.0, "title": "Easten Antarctic Peninsula Surface Sediment Diatom Data", "uid": "601211", "west": -64.0}, {"awards": "1443680 Smith, Craig", "bounds_geometry": ["POLYGON((-65.561 -64.6538,-65.2471 -64.6538,-64.9332 -64.6538,-64.6193 -64.6538,-64.3054 -64.6538,-63.9915 -64.6538,-63.6776 -64.6538,-63.3637 -64.6538,-63.0498 -64.6538,-62.7359 -64.6538,-62.422 -64.6538,-62.422 -64.67842,-62.422 -64.70304,-62.422 -64.72766,-62.422 -64.75228,-62.422 -64.7769,-62.422 -64.80152,-62.422 -64.82614,-62.422 -64.85076,-62.422 -64.87538,-62.422 -64.9,-62.7359 -64.9,-63.0498 -64.9,-63.3637 -64.9,-63.6776 -64.9,-63.9915 -64.9,-64.3054 -64.9,-64.6193 -64.9,-64.9332 -64.9,-65.2471 -64.9,-65.561 -64.9,-65.561 -64.87538,-65.561 -64.85076,-65.561 -64.82614,-65.561 -64.80152,-65.561 -64.7769,-65.561 -64.75228,-65.561 -64.72766,-65.561 -64.70304,-65.561 -64.67842,-65.561 -64.6538))"], "date_created": "Tue, 16 Jul 2019 00:00:00 GMT", "description": "This dataset includes Pb-210 activities, grain-size distributions, and x-radiograph negatives for cores collected primarily during NBP1603 (and also LMG1510) as part of the FjordEco project in Andvord Bay and surrounding areas (Gerlache Strait, and Station B on the shelf). Data are from subsampled intervals of kasten cores and box cores, as well as one megacore. Samples were x-rayed, sliced, and bagged onboard the vessel. Grain-size and Pb-210 analyses were completed in the Sediment Dynamics Lab within the University of Washington School of Oceanography (PI C. Nittrouer).", "east": -62.422, "geometry": ["POINT(-63.9915 -64.7769)"], "keywords": "Antarctica; Geochronology; Grain Size; LMG1510; NBP1603; Sediment; Sediment Core Data", "locations": "Antarctica", "north": -64.6538, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Eidam, Emily; Nittrouer, Charles; Homolka, Khadijah; Smith, Craig", "project_titles": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "projects": [{"proj_uid": "p0010010", "repository": "USAP-DC", "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.9, "title": "Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)", "uid": "601193", "west": -65.561}, {"awards": "1246357 Bart, Philip", "bounds_geometry": ["POLYGON((-171 -75.8,-170.5 -75.8,-170 -75.8,-169.5 -75.8,-169 -75.8,-168.5 -75.8,-168 -75.8,-167.5 -75.8,-167 -75.8,-166.5 -75.8,-166 -75.8,-166 -75.99,-166 -76.18,-166 -76.37,-166 -76.56,-166 -76.75,-166 -76.94,-166 -77.13,-166 -77.32,-166 -77.51,-166 -77.7,-166.5 -77.7,-167 -77.7,-167.5 -77.7,-168 -77.7,-168.5 -77.7,-169 -77.7,-169.5 -77.7,-170 -77.7,-170.5 -77.7,-171 -77.7,-171 -77.51,-171 -77.32,-171 -77.13,-171 -76.94,-171 -76.75,-171 -76.56,-171 -76.37,-171 -76.18,-171 -75.99,-171 -75.8))"], "date_created": "Mon, 03 Jun 2019 00:00:00 GMT", "description": "Still and video benthic images collected during expedition NBP1502 in the Ross Sea using a YoYo camera system.", "east": -166.0, "geometry": ["POINT(-168.5 -76.75)"], "keywords": "Antarctica; Benthic; Benthic Images; Benthos; Bentic Fauna; Camera Tow; Marine Geoscience; Marine Sediments; NBP1502; Photo; Photo/video; Photo/Video; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Yoyo Camera", "locations": "Southern Ocean; Ross Sea; Antarctica", "north": -75.8, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bart, Philip", "project_titles": "Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf", "projects": [{"proj_uid": "p0000877", "repository": "USAP-DC", "title": "Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.7, "title": "NBP1502 YoYo camera benthic images from Ross Sea", "uid": "601182", "west": -171.0}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": ["POLYGON((70 -68,70.5 -68,71 -68,71.5 -68,72 -68,72.5 -68,73 -68,73.5 -68,74 -68,74.5 -68,75 -68,75 -68.2,75 -68.4,75 -68.6,75 -68.8,75 -69,75 -69.2,75 -69.4,75 -69.6,75 -69.8,75 -70,74.5 -70,74 -70,73.5 -70,73 -70,72.5 -70,72 -70,71.5 -70,71 -70,70.5 -70,70 -70,70 -69.8,70 -69.6,70 -69.4,70 -69.2,70 -69,70 -68.8,70 -68.6,70 -68.4,70 -68.2,70 -68))"], "date_created": "Fri, 10 May 2019 00:00:00 GMT", "description": "This dataset contains 14C data, magnetic susceptibility, relative grain size percentages, 10Be", "east": 75.0, "geometry": ["POINT(72.5 -69)"], "keywords": "Antarctica; Be-10; Glaciers/ice Sheet; Glaciers/Ice Sheet; Grain Size; Late Quaternary; Magnetic Susceptibility; Mass Spectrometry; NBP0101; Paleoenvironment; Prydz Bay; Radiocarbon; R/v Nathaniel B. Palmer; Sediment; Sediment Core; Sediment Core Data", "locations": "Antarctica; Prydz Bay", "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Shevenell, Amelia", "project_titles": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "projects": [{"proj_uid": "p0000381", "repository": "USAP-DC", "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Geochemical and sedimentologic data from NBP01-01 JPC-34", "uid": "601180", "west": 70.0}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": ["POLYGON((57 -66,57.3 -66,57.6 -66,57.9 -66,58.2 -66,58.5 -66,58.8 -66,59.1 -66,59.4 -66,59.7 -66,60 -66,60 -66.1,60 -66.2,60 -66.3,60 -66.4,60 -66.5,60 -66.6,60 -66.7,60 -66.8,60 -66.9,60 -67,59.7 -67,59.4 -67,59.1 -67,58.8 -67,58.5 -67,58.2 -67,57.9 -67,57.6 -67,57.3 -67,57 -67,57 -66.9,57 -66.8,57 -66.7,57 -66.6,57 -66.5,57 -66.4,57 -66.3,57 -66.2,57 -66.1,57 -66))"], "date_created": "Thu, 25 Apr 2019 00:00:00 GMT", "description": "This data set describes diatom assemblages and abundances from two sediment cores retrieved from Edward VIII Gulf. The assemblages are used to reconstruct paleoceanographic conditions throughout the Holocene.", "east": 60.0, "geometry": ["POINT(58.5 -66.5)"], "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "locations": "East Antarctica; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy", "project_titles": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "projects": [{"proj_uid": "p0000609", "repository": "USAP-DC", "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "uid": "601177", "west": 57.0}, {"awards": "1758224 Salvatore, Mark", "bounds_geometry": ["POLYGON((-180 -83,-177 -83,-174 -83,-171 -83,-168 -83,-165 -83,-162 -83,-159 -83,-156 -83,-153 -83,-150 -83,-150 -83.5,-150 -84,-150 -84.5,-150 -85,-150 -85.5,-150 -86,-150 -86.5,-150 -87,-150 -87.5,-150 -88,-153 -88,-156 -88,-159 -88,-162 -88,-165 -88,-168 -88,-171 -88,-174 -88,-177 -88,180 -88,177 -88,174 -88,171 -88,168 -88,165 -88,162 -88,159 -88,156 -88,153 -88,150 -88,150 -87.5,150 -87,150 -86.5,150 -86,150 -85.5,150 -85,150 -84.5,150 -84,150 -83.5,150 -83,153 -83,156 -83,159 -83,162 -83,165 -83,168 -83,171 -83,174 -83,177 -83,-180 -83))"], "date_created": "Fri, 15 Mar 2019 00:00:00 GMT", "description": "This data set contains reflectance spectra (350 - 2500 nm) of a range of rocks and sediments from the Central Transantarctic Mountains. Data were acquired using an Analytical Spectral Devices (ASD) FieldSpec4 high-resolution spectrometer under illumination with a high-output halogen bulb, with illumination and observation angles fixed at 0 and 30 degrees off-nadir, respectively. Data were acquired for the purposes of validation and \u0027ground truthing\u0027 of orbital multispectral data.", "east": -150.0, "geometry": ["POINT(180 -85.5)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Remote Sensing; Rocks; Solid Earth; Spectroscopy; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -83.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Salvatore, Mark", "project_titles": "EAGER: Surface Variability and Spectral Analyses of the Central Transantarctic Mountains, Antarctica", "projects": [{"proj_uid": "p0010020", "repository": "USAP-DC", "title": "EAGER: Surface Variability and Spectral Analyses of the Central Transantarctic Mountains, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -88.0, "title": "Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments", "uid": "601163", "west": 150.0}, {"awards": "1443680 Smith, Craig", "bounds_geometry": ["POLYGON((-65 -64,-64.7 -64,-64.4 -64,-64.1 -64,-63.8 -64,-63.5 -64,-63.2 -64,-62.9 -64,-62.6 -64,-62.3 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.3 -65,-62.6 -65,-62.9 -65,-63.2 -65,-63.5 -65,-63.8 -65,-64.1 -65,-64.4 -65,-64.7 -65,-65 -65,-65 -64.9,-65 -64.8,-65 -64.7,-65 -64.6,-65 -64.5,-65 -64.4,-65 -64.3,-65 -64.2,-65 -64.1,-65 -64))"], "date_created": "Wed, 13 Feb 2019 00:00:00 GMT", "description": "Sediment organic carbon and organic nitrogen content (percent mass) in 6 depth intervals (0-1cm, 1-2cm, 3-4cm, 5-6cm, 7-8cm , 9-10cm) in sediment cores collected by OSIL Megacore (10 cm diameter tubes) along the five-station FjordEco Transect from inner Andvord Bay to the open continental shelf at FOODBANCS Station B. \r\n", "east": -62.0, "geometry": ["POINT(-63.5 -64.5)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice", "locations": "Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Smith, Craig", "project_titles": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "projects": [{"proj_uid": "p0010010", "repository": "USAP-DC", "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "FjordEco", "south": -65.0, "title": "Fjord-Eco_Sediment_OrgC_OrgN_Data - Craig Smith", "uid": "601157", "west": -65.0}, {"awards": "1048343 Warny, Sophie", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Fri, 01 Feb 2019 00:00:00 GMT", "description": "Thanks to grant # U.S. National Science Foundation ANT-1048343, our group was selected to study about 700 of the recently-acquired sediment samples in Antarctica, covering ~9 regions and geological time frames ranging from the Paleocene to today. The samples were processed for palynological analyses and the slides are curated at the LSU CENEX center.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Glaciology; Marine Geoscience; Marine Sediments; Microscope; Microscopy; Paleoclimate; Pollen", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Warny, Sophie", "project_titles": "CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program", "projects": [{"proj_uid": "p0000311", "repository": "USAP-DC", "title": "CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Palynological samples", "uid": "601151", "west": -180.0}, {"awards": "1341585 Sorlien, Christopher", "bounds_geometry": ["POLYGON((-180 -73.22,-179.17 -73.22,-178.34 -73.22,-177.51 -73.22,-176.68 -73.22,-175.85 -73.22,-175.02 -73.22,-174.19 -73.22,-173.36 -73.22,-172.53 -73.22,-171.7 -73.22,-171.7 -73.765,-171.7 -74.31,-171.7 -74.855,-171.7 -75.4,-171.7 -75.945,-171.7 -76.49,-171.7 -77.035,-171.7 -77.58,-171.7 -78.125,-171.7 -78.67,-172.53 -78.67,-173.36 -78.67,-174.19 -78.67,-175.02 -78.67,-175.85 -78.67,-176.68 -78.67,-177.51 -78.67,-178.34 -78.67,-179.17 -78.67,180 -78.67,178.56 -78.67,177.12 -78.67,175.68 -78.67,174.24 -78.67,172.8 -78.67,171.36 -78.67,169.92 -78.67,168.48 -78.67,167.04 -78.67,165.6 -78.67,165.6 -78.125,165.6 -77.58,165.6 -77.035,165.6 -76.49,165.6 -75.945,165.6 -75.4,165.6 -74.855,165.6 -74.31,165.6 -73.765,165.6 -73.22,167.04 -73.22,168.48 -73.22,169.92 -73.22,171.36 -73.22,172.8 -73.22,174.24 -73.22,175.68 -73.22,177.12 -73.22,178.56 -73.22,-180 -73.22))"], "date_created": "Fri, 25 May 2018 00:00:00 GMT", "description": "This data set includes digital 1 km grids of sub-bottom \n\tstratigraphy of most of Ross Sea. In addition to acoustic basement (same as top\n\tsyn-rift sedimentary rocks in Central Trough and probably other basins), these\n\tgrids include Oligocene and Miocene horizons that are unconformities in most\n\tareas. A sea floor grid is also included. Except for the sea floor grid, the\n\tgrids are trimmed to be relatively close to control of interpreted seismic\n\tstratigraphy. The grids are provided in two way travel time and in depth. Math\n\tcan be performed on the corresponding time and depth grids to recreate the 3D\n\tinterval velocity model that was used. The velocity of the water used was 1450\n\tm/s. More detailed descriptions of the work are found in the Final NSF report\n\tfor PLR1341585 by C. Sorlien, B. Luyendyk, and D. Wilson. The grids are\n\tcontinuous so are merged with the sea floor where there is outcrop, or with\n\tbasement if there is onlap, or with a young unconformity where there is\n\tsub-bottom truncation. The filenames include the name of the horizon\n\t(unconformity) and whether they are in time or depth. \\\"etc.\\\" means there are\n\ttwo or more horizons that have been merged. Most of the horizons are named and\n\tdefined in the ANTOSTRAT (1995) atlas. The starting points for many of these\n\thorizons are ANTOSTRAT [1995] near DSDP sites 273, 272, and 270. In other areas\n\twe deviate from the interpretation of ANTOSTRAT [1995]. late Oligocene through\n\tmiddle Miocene horizons, interpreted very close to the ANTOSTRAT [1995] at DSDP\n\tSite 273 in Central Trough, are much deeper in our interpretation within Terror\n\tRift. These horizon grids usually include the sea floor where there is outcrop\n\tor acoustic basement (top syn-rift in some basins) where there is onlap. \n\n\n\tANTOSTRAT (1995), Seismic Stratigraphic Atlas of the Ross Sea, in Geology and\n\tSeismic Stratigraphy of the Antarctic Margin, edited by A. K. Cooper, Barker,\n\tP. F., Brancolini, G., 22 plates, American Geophysical Union, Washington,\n\tD.C.", "east": -171.7, "geometry": ["POINT(176.95 -75.945)"], "keywords": "Antarctica; Continental Margin; Geology/Geophysics - Other; Marine Geoscience; Miocene; Oligocene; Seismic Reflection", "locations": "Antarctica", "north": -73.22, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Sorlien, Christopher; Wilson, Douglas S.", "project_titles": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea", "projects": [{"proj_uid": "p0000271", "repository": "USAP-DC", "title": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.67, "title": "Ross Sea unconformities digital grids in depth and two-way time", "uid": "601098", "west": 165.6}, {"awards": "1341729 Kirschvink, Joseph", "bounds_geometry": ["POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))"], "date_created": "Fri, 27 Apr 2018 00:00:00 GMT", "description": "", "east": -56.2, "geometry": ["POINT(-57.55 -64.1)"], "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; Glaciology; James Ross Basin; Marine Geoscience; Marine Sediments", "locations": "James Ross Basin; Antarctica", "north": -63.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Skinner, Steven; Kirschvink, Joseph", "project_titles": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica", "projects": [{"proj_uid": "p0000276", "repository": "USAP-DC", "title": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.7, "title": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica", "uid": "601094", "west": -58.9}, {"awards": "1246353 Anderson, John", "bounds_geometry": ["POLYGON((-180 -74.37,-178.85 -74.37,-177.7 -74.37,-176.55 -74.37,-175.4 -74.37,-174.25 -74.37,-173.1 -74.37,-171.95 -74.37,-170.8 -74.37,-169.65 -74.37,-168.5 -74.37,-168.5 -74.747,-168.5 -75.124,-168.5 -75.501,-168.5 -75.878,-168.5 -76.255,-168.5 -76.632,-168.5 -77.009,-168.5 -77.386,-168.5 -77.763,-168.5 -78.14,-169.65 -78.14,-170.8 -78.14,-171.95 -78.14,-173.1 -78.14,-174.25 -78.14,-175.4 -78.14,-176.55 -78.14,-177.7 -78.14,-178.85 -78.14,180 -78.14,178.48 -78.14,176.96 -78.14,175.44 -78.14,173.92 -78.14,172.4 -78.14,170.88 -78.14,169.36 -78.14,167.84 -78.14,166.32 -78.14,164.8 -78.14,164.8 -77.763,164.8 -77.386,164.8 -77.009,164.8 -76.632,164.8 -76.255,164.8 -75.878,164.8 -75.501,164.8 -75.124,164.8 -74.747,164.8 -74.37,166.32 -74.37,167.84 -74.37,169.36 -74.37,170.88 -74.37,172.4 -74.37,173.92 -74.37,175.44 -74.37,176.96 -74.37,178.48 -74.37,-180 -74.37))"], "date_created": "Mon, 05 Feb 2018 00:00:00 GMT", "description": "Dataset includes details of cores collected as part of cruise NBP1502A, a list of radiocarbon-dated samples and samples to be radiocarbon-dated, and grain-size data from select NBP1502A cores.", "east": -168.5, "geometry": ["POINT(178.15 -76.255)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochronology; Marine Geoscience; Marine Sediments; NBP1502; R/v Nathaniel B. Palmer; Sediment Core", "locations": "Antarctica", "north": -74.37, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Simkins, Lauren; Anderson, John; Prothro, Lindsay", "project_titles": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum.", "projects": [{"proj_uid": "p0000395", "repository": "USAP-DC", "title": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.14, "title": "NBP1502A Cruise Core Data", "uid": "601083", "west": 164.8}, {"awards": "1341669 DeMaster, David", "bounds_geometry": ["POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))"], "date_created": "Sat, 03 Feb 2018 00:00:00 GMT", "description": "This file has C-14 data from the organic matter fraction of Antarctic marine sediments, collected from the collapsed Larsen Ice Shelf and the West Antarctic Peninsula", "east": -58.0, "geometry": ["POINT(-64 -65)"], "keywords": null, "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "DeMaster, David", "project_titles": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "projects": [{"proj_uid": "p0000382", "repository": "USAP-DC", "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data", "uid": "601082", "west": -70.0}, {"awards": "0732917 McCormick, Michael", "bounds_geometry": ["POLYGON((299.4 -63.1,299.92 -63.1,300.44 -63.1,300.96 -63.1,301.48 -63.1,302 -63.1,302.52 -63.1,303.04 -63.1,303.56 -63.1,304.08 -63.1,304.6 -63.1,304.6 -63.29,304.6 -63.48,304.6 -63.67,304.6 -63.86,304.6 -64.05,304.6 -64.24,304.6 -64.43,304.6 -64.62,304.6 -64.81,304.6 -65,304.08 -65,303.56 -65,303.04 -65,302.52 -65,302 -65,301.48 -65,300.96 -65,300.44 -65,299.92 -65,299.4 -65,299.4 -64.81,299.4 -64.62,299.4 -64.43,299.4 -64.24,299.4 -64.05,299.4 -63.86,299.4 -63.67,299.4 -63.48,299.4 -63.29,299.4 -63.1))"], "date_created": "Sun, 17 Dec 2017 00:00:00 GMT", "description": "Ice-shelf loss along the east coast of the Antarctic Peninsula over recent decades has brought new sources of carbon and energy to the marine benthos likely affecting sediment geochemistry and microbial community composition. To better understand the long-term effects of ice-shelf loss on benthic microbial communities, we conducted a five-station survey along a 160 km transect following the historic path of retreat of the Larsen A ice shelf. All microbial community sequence data is publicly available through the Metagenomics Analysis Server at Argonne National Laboratory (MG-RAST). The project title is \"Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula\". A key word search using terms from this title at the MG-RAST portal (http://metagenomics.anl.gov/) will return the complete sample list. This submitted dataset summarizes the measured environmental parameters for these same samples (lat., long., water depth, sediment depth, pH, alkalinity, dissolved oxygen, silicate, phosphate, nitrate, nitrite, and ammonium).", "east": 304.6, "geometry": ["POINT(-58 -64.05)"], "keywords": "Antarctica; Antarctic Peninsula; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; LARISSA; Microbiology", "locations": "Antarctica; Antarctic Peninsula", "north": -63.1, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "McCormick, Michael", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems.", "projects": [{"proj_uid": "p0010135", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "LARISSA: Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula", "uid": "601073", "west": 299.4}, {"awards": "1143834 Huber, Bruce", "bounds_geometry": ["POINT(120.5 -66.2)"], "date_created": "Wed, 15 Nov 2017 00:00:00 GMT", "description": "Time series of temperature and salinity from a sediment trap mooring deployed during NBP1402 on 04 March 2014 at 66S 11, 122 E 30.2, depth 547 m. The mooring was recovered from Aurora Australis on 26 December 2014 ", "east": 120.5, "geometry": ["POINT(120.5 -66.2)"], "keywords": "Antarctica; Mooring; NBP1402; Oceans; Physical Oceanography; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean", "locations": "Sabrina Coast; Southern Ocean; Antarctica", "north": -66.2, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Huber, Bruce", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.2, "title": "Sabrina Coast mooring data - sediment trap mooring 2014", "uid": "601069", "west": 120.5}, {"awards": "1341500 Ryberg, Patricia", "bounds_geometry": null, "date_created": "Tue, 07 Nov 2017 00:00:00 GMT", "description": "Images of Late Permian glossopterid reproductive structures from Allan Hills in the Beardmore Glacier Region of Antarctica.", "east": null, "geometry": null, "keywords": "Antarctica; Biota; Fossil; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Ryberg, Patricia", "project_titles": "RUI: Antarctic Paleobotany: Permian Floral Characteristics in a Sedimentary Setting", "projects": [{"proj_uid": "p0010134", "repository": "USAP-DC", "title": "RUI: Antarctic Paleobotany: Permian Floral Characteristics in a Sedimentary Setting"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Images of Fossil Plants of Antarctica", "uid": "601066", "west": null}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": ["POLYGON((-65.32 -64.15,-65.309 -64.15,-65.298 -64.15,-65.287 -64.15,-65.276 -64.15,-65.265 -64.15,-65.254 -64.15,-65.243 -64.15,-65.232 -64.15,-65.221 -64.15,-65.21 -64.15,-65.21 -64.186,-65.21 -64.222,-65.21 -64.258,-65.21 -64.294,-65.21 -64.33,-65.21 -64.366,-65.21 -64.402,-65.21 -64.438,-65.21 -64.474,-65.21 -64.51,-65.221 -64.51,-65.232 -64.51,-65.243 -64.51,-65.254 -64.51,-65.265 -64.51,-65.276 -64.51,-65.287 -64.51,-65.298 -64.51,-65.309 -64.51,-65.32 -64.51,-65.32 -64.474,-65.32 -64.438,-65.32 -64.402,-65.32 -64.366,-65.32 -64.33,-65.32 -64.294,-65.32 -64.258,-65.32 -64.222,-65.32 -64.186,-65.32 -64.15))"], "date_created": "Wed, 25 Oct 2017 00:00:00 GMT", "description": "These are unpublished stable isotope data from a series of sediment cores collected during LMG12-11 and LMG13-11 down the axis of Anvers Trough. These records span the LMG to recent.", "east": -65.21, "geometry": ["POINT(-65.265 -64.33)"], "keywords": "Antarctica; Antarctic Peninsula; Anvers Trough; Chemistry:sediment; Chemistry:Sediment; Foraminifera; Geochemistry; Isotope; LMG1211; LMG1311; Marine Sediments; Oceans; Paleoclimate; Sample/collection Description; Sample/Collection Description; Southern Ocean", "locations": "Antarctic Peninsula; Anvers Trough; Antarctica; Southern Ocean", "north": -64.15, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Shevenell, Amelia", "project_titles": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "projects": [{"proj_uid": "p0000381", "repository": "USAP-DC", "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.51, "title": "Anvers Trough Foraminifer Stable Isotope data", "uid": "601064", "west": -65.32}, {"awards": "1430550 Domack, Eugene", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Pollen assemblage data for Paleocene to early to middle Eocene sediments collected on Totten continental shelf, East Antarctica. ", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Biota; Marine Sediments; NBP1402; Oceans; Paleoclimate; Pollen; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "locations": "Southern Ocean; Antarctica; Sabrina Coast; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Shevenell, Amelia; Smith, Catherine; Domack, Eugene Walter", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data", "uid": "601046", "west": 120.0}, {"awards": "1430550 Domack, Eugene", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Bulk sediment carbon and nitrogen data data for Paleocene sediments collected on Totten continental shelf, East Antarctica. ", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Carbon; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Marine Sediments; NBP1402; Nitrogen; Oceans; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "locations": "Southern Ocean; Antarctica; Sabrina Coast; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Smith, Catherine; Shevenell, Amelia; Domack, Eugene Walter", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data", "uid": "601044", "west": 120.0}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Foraminifer assemblage data for Paleocene sediments collected on Totten continental shelf, East Antarctica.", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Biota; Continental Margin; Foraminifera; NBP1402; Oceans; Paleoclimate; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean; Totten Glacier", "locations": "Southern Ocean; Antarctica; Sabrina Coast; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Shevenell, Amelia; Leventer, Amy", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-55 foraminifer assemblage data", "uid": "601042", "west": 120.0}, {"awards": "1043554 Willenbring, Jane", "bounds_geometry": ["POINT(161.5 -77.5)"], "date_created": "Wed, 09 Nov 2016 00:00:00 GMT", "description": "The PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events.\nThis study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K-12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete.", "east": 161.5, "geometry": ["POINT(161.5 -77.5)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic Radionuclides; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Isotope; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -77.5, "nsf_funding_programs": null, "persons": "Willenbring, Jane", "project_titles": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "projects": [{"proj_uid": "p0000429", "repository": "USAP-DC", "title": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "uid": "600379", "west": 161.5}, {"awards": "0839059 Powell, Ross", "bounds_geometry": ["POLYGON((-168.7 -82.3,-168.69 -82.3,-168.68 -82.3,-168.67 -82.3,-168.66 -82.3,-168.65 -82.3,-168.64 -82.3,-168.63 -82.3,-168.62 -82.3,-168.61 -82.3,-168.6 -82.3,-168.6 -82.31,-168.6 -82.32,-168.6 -82.33,-168.6 -82.34,-168.6 -82.35,-168.6 -82.36,-168.6 -82.37,-168.6 -82.38,-168.6 -82.39,-168.6 -82.4,-168.61 -82.4,-168.62 -82.4,-168.63 -82.4,-168.64 -82.4,-168.65 -82.4,-168.66 -82.4,-168.67 -82.4,-168.68 -82.4,-168.69 -82.4,-168.7 -82.4,-168.7 -82.39,-168.7 -82.38,-168.7 -82.37,-168.7 -82.36,-168.7 -82.35,-168.7 -82.34,-168.7 -82.33,-168.7 -82.32,-168.7 -82.31,-168.7 -82.3))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF\u0027s Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling.\nThe latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations.\nSocietal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.", "east": -168.6, "geometry": ["POINT(-168.65 -82.35)"], "keywords": "Antarctica; Biota; Diatom; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Whillans; Paleoclimate; Ross Sea; Southern Ocean; Subglacial Lake; WISSARD", "locations": "Southern Ocean; Lake Whillans; Ross Sea; Antarctica", "north": -82.3, "nsf_funding_programs": null, "persons": "Powell, Ross", "project_titles": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "projects": [{"proj_uid": "p0000105", "repository": "USAP-DC", "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.4, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD)", "uid": "600154", "west": -168.7}, {"awards": "0839031 Severinghaus, Jeffrey", "bounds_geometry": ["POINT(161.71965 -77.76165)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \u0027clathrate hypothesis\u0027 that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \u0027horizontal ice core\u0027 would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.71965, "geometry": ["POINT(161.71965 -77.76165)"], "keywords": "Antarctica; Cosmogenic; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains; Taylor Glacier", "north": -77.76165, "nsf_funding_programs": null, "persons": "Severinghaus, Jeffrey P.", "project_titles": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "projects": [{"proj_uid": "p0000099", "repository": "USAP-DC", "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.76165, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "uid": "600165", "west": 161.71965}, {"awards": "0944282 Hasiotis, Stephen", "bounds_geometry": ["POINT(175 -86)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This proposal will study the diversity, abundance, and tiering patterns of ichnofossils in continental and marine deposits of the Beacon Supergroup in the Beardmore Glacier Area (BGA). The PIs will focus on continental strata that contain a variety of ichnofossils and paleosols. Ichnofossils will be evaluated for their architectural and surficial morphologies, and will be compared to modern and ancient traces to interpret the tracemaker behavior and paleoenvironmental setting. Distribution of ichnofossils within these units may indicate the effect of lateral variability of pedogenesis, the magnitude and frequency of depositional events, and the amount of moisture within the sediment, as well as the effects of climate change. The paleoclimatic significance of ichnofossils will be determined by comparing the burrow size, occurrence, tiering, and pedogenic significance of ichnofossils in measured sections of stratigraphic units deposited during global warming and cooling episodes. Comparisons will be made between BGA formations to stratigraphically equivalent rocks deposited at low paleolatitudes with previously determined paleoclimatic settings. The objectives of this project are to address two major questions: what differences existed in ichnodiversity, abundance, and tiering in marine and continental deposits between high- and low-paleolatitudes, and was there a dearth of habitat usage in continental deposits during the late Paleozoic and Mesozoic, particularly in fluvial and lacustrine environments compared to the habitat usage in the marine realm at that time?\nThis study will enhance the ability to interpret paleoenvironments to the subenvironmental scale, understand the evolution of soil biota and ecosystems at high paleolatitudes, determine the role of organisms in soil formation at high paleolatitudes, explore the effects of climate change on the body size and diversity of organisms in the soil communities, and develop new tools to interpret paleoclimate in high latitudes. There is a strong education component associated with this proposal.", "east": 175.0, "geometry": ["POINT(175 -86)"], "keywords": "Antarctica; Beardmore Glacier; Biota; Fossil; Paleoclimate; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Beardmore Glacier; Transantarctic Mountains", "north": -86.0, "nsf_funding_programs": null, "persons": "Hasiotis, Stephen", "project_titles": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica", "projects": [{"proj_uid": "p0000423", "repository": "USAP-DC", "title": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica", "uid": "600156", "west": 175.0}, {"awards": "0839107 Powell, Ross", "bounds_geometry": ["POLYGON((-163.7 -84,-163.68 -84,-163.66 -84,-163.64 -84,-163.62 -84,-163.6 -84,-163.58 -84,-163.56 -84,-163.54 -84,-163.52 -84,-163.5 -84,-163.5 -84.05,-163.5 -84.1,-163.5 -84.15,-163.5 -84.2,-163.5 -84.25,-163.5 -84.3,-163.5 -84.35,-163.5 -84.4,-163.5 -84.45,-163.5 -84.5,-163.52 -84.5,-163.54 -84.5,-163.56 -84.5,-163.58 -84.5,-163.6 -84.5,-163.62 -84.5,-163.64 -84.5,-163.66 -84.5,-163.68 -84.5,-163.7 -84.5,-163.7 -84.45,-163.7 -84.4,-163.7 -84.35,-163.7 -84.3,-163.7 -84.25,-163.7 -84.2,-163.7 -84.15,-163.7 -84.1,-163.7 -84.05,-163.7 -84))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "The RAGES project (Robotic Access to Grounding zones for Exploration and Science) is one of three research components of the WISSARD (Whillans Ice Stream Subglacial Access Research Drilling) integrative initiative that is being funded by the Antarctic Integrated System Science Program of NSF\u0027s Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The RAGES component of WISSARD concentrates on the stability of ice stream grounding zones (GZ), the area where the ice, ocean waters and glacial and sea floor sediment interact. Based on our present limited data and modeling efforts, GZs can be perturbed by (i) internal ice stream dynamics, (ii) filling/draining cycles of subglacial lakes, (iii) increased melting by warming ocean waters, and/or (iv) rates of subglacial sediment (till) supply to the GZ. GZs are seen as high priority targets to investigate due to their unknown contributions to ice sheet stability under future global warming scenarios. The three main science goals for RAGES are to assess: (a) West Antarctic Ice Sheet (WAIS) stability relative to the magnitudes of the four main variables listed above; (b) the degree to which grounding-zone sedimentary systems house important records of past WAIS dynamics; and (c) the importance of microbial activity and subglacial geochemical weathering in supplying nutrients to the WAIS grounding zone, the Ross Ice Shelf (RIS) cavity, and the highly productive Southern Ocean that may ultimately influence global biogeochemical cycles. The RAGES field sampling plan integrates surface geophysical surveys with borehole and subglacial sampling and measurements. The boreholes provide: (1) samples of subglacial water, sediments, and basal ice for biological, geochemical, glaciological, sedimentological, and micropaleontological analyses; (2) measures of subglacial and sub-ice-shelf cavity physical and chemical conditions and their spatial variability; and (3) data on sediment types, state and change of the subglacial water discharge, oceanography, and basal ice at the grounding line and within the nearby sub-ice-shelf cavity. Unique tools to be deployed include a multisensor Sub-Ice ROVer (Remotely Operated Vehicle) and long-term, sub-ice oceanographic moorings.\nThe latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations.\nSocietal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. The RAGES project represents a significant advance in polar technology by incorporating the use of complex new instrumentation like the Sub-Ice ROVer and subglacial ocean/lake mooring systems. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.", "east": -163.5, "geometry": ["POINT(-163.6 -84.25)"], "keywords": "Antarctica; Glaciology; Oceans; Southern Ocean; WISSARD", "locations": "Southern Ocean; Antarctica", "north": -84.0, "nsf_funding_programs": null, "persons": "Powell, Ross", "project_titles": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "projects": [{"proj_uid": "p0000105", "repository": "USAP-DC", "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.5, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES)", "uid": "600155", "west": -163.7}, {"awards": "1303896 Kirschvink, Joseph", "bounds_geometry": ["POLYGON((-57 -63,-56.9 -63,-56.8 -63,-56.7 -63,-56.6 -63,-56.5 -63,-56.4 -63,-56.3 -63,-56.2 -63,-56.1 -63,-56 -63,-56 -63.2,-56 -63.4,-56 -63.6,-56 -63.8,-56 -64,-56 -64.2,-56 -64.4,-56 -64.6,-56 -64.8,-56 -65,-56.1 -65,-56.2 -65,-56.3 -65,-56.4 -65,-56.5 -65,-56.6 -65,-56.7 -65,-56.8 -65,-56.9 -65,-57 -65,-57 -64.8,-57 -64.6,-57 -64.4,-57 -64.2,-57 -64,-57 -63.8,-57 -63.6,-57 -63.4,-57 -63.2,-57 -63))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "The PI will collect samples to extend the magneto-stratigraphic record of late Cretaceous sediments of the James Ross Basin, Antarctica. RAPID support will allow him to take advantage of an invitation from the Instituto Antartico Argentino (IAA) to participate on an excursion to James Ross Island in the Antarctic Peninsula. The PI hopes to collect samples that will refine the position of several geomagnetic reversals between the end of the Cretaceous long normal Chron and the lower portion of Chron 31R. The Brandy Bay locality targeted by this expedition is the best place in the basin for calibrating the biostratigraphic position of the top of the Cretaceous Long Normal Chron, which is one of the most reliable correlation horizons in the entire Geological Time Scale.\n\nThe top of the Cretaceous long normal Chron is not properly correlated to southern hemisphere biostratigraphy. Locating this event will be a major addition to understanding geological time. This expedition will provide opportunities for an undergraduate student. This project is based on a productive collaboration with an Argentine scientist.", "east": -56.0, "geometry": ["POINT(-56.5 -64)"], "keywords": "Antarctica; GPS; James Ross Basin; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Antarctica; James Ross Basin", "north": -63.0, "nsf_funding_programs": null, "persons": "Kirschvink, Joseph", "project_titles": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica", "projects": [{"proj_uid": "p0000419", "repository": "USAP-DC", "title": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica", "uid": "600136", "west": -57.0}, {"awards": "1043740 Lenczewski, Melissa", "bounds_geometry": ["POLYGON((165 -77.5,165.3 -77.5,165.6 -77.5,165.9 -77.5,166.2 -77.5,166.5 -77.5,166.8 -77.5,167.1 -77.5,167.4 -77.5,167.7 -77.5,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,168 -78.1,168 -78.2,168 -78.3,168 -78.4,168 -78.5,167.7 -78.5,167.4 -78.5,167.1 -78.5,166.8 -78.5,166.5 -78.5,166.2 -78.5,165.9 -78.5,165.6 -78.5,165.3 -78.5,165 -78.5,165 -78.4,165 -78.3,165 -78.2,165 -78.1,165 -78,165 -77.9,165 -77.8,165 -77.7,165 -77.6,165 -77.5))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "The PI proposes to utilize computer models used by hydrogeologists to establish the fate and transport of contamination and determine the extent of drilling fluid contamination in the ANDRILL SMS core. For these models, previously collected logs of lithology, porosity, fracture density, fracture type, fracture orientation, drilling fluid loss, drilling fluid characteristics and temperature will be used as input parameters. In addition, biodegradation and sorption constants for the drilling fluid will be determined and incorporated into the models. Samples of drilling fluids used during coring as well as the return fluids were collected at the drill site using standard microbiological sampling techniques. Fluids will be tested at in situ temperatures under aerobic and anaerobic conditions to determine biodegradation constants. Sorption will be determined between the drilling fluids and core samples using standard isotherm methods. Geochemical and microbial fingerprints of the fluids and the changes during biodegradation will determine the potential impact of the drilling fluids on the isolated microbial communities and the geochemistry within various subsurface lithologic units beneath the southern McMurdo Sound in Antarctica. The results of this study could potentially provide guidelines on developing less detrimental methods for future exploration, if deemed necessary through this research.\nThis proposed project will train a graduate student. The methods developed for analyses of samples in this project will serve as a guide for future studies of similar interest and will improve the understanding of ecological impacts of geologic drilling in Antarctica. The results of this study will be used as a reference for comparison with future studies examining newly developed, and improved, sample collection methods in future exploratory drilling projects in pristine environments. The PI is new to Antarctic research.\n", "east": 168.0, "geometry": ["POINT(166.5 -78)"], "keywords": "Andrill; Antarctica; Chemistry:fluid; Chemistry:Fluid; Chemistry:rock; Chemistry:Rock; Drilling Fluid; Geochemistry; McMurdo; Ross Sea; Sediment Core", "locations": "Antarctica; McMurdo; Ross Sea", "north": -77.5, "nsf_funding_programs": null, "persons": "Lenczewski, Melissa", "project_titles": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)", "projects": [{"proj_uid": "p0000468", "repository": "USAP-DC", "title": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -78.5, "title": "Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)", "uid": "600129", "west": 165.0}, {"awards": "1354231 Kowalewski, Douglas", "bounds_geometry": ["POLYGON((-160 -70,-156 -70,-152 -70,-148 -70,-144 -70,-140 -70,-136 -70,-132 -70,-128 -70,-124 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-124 -85,-128 -85,-132 -85,-136 -85,-140 -85,-144 -85,-148 -85,-152 -85,-156 -85,-160 -85,-160 -83.5,-160 -82,-160 -80.5,-160 -79,-160 -77.5,-160 -76,-160 -74.5,-160 -73,-160 -71.5,-160 -70))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Neogene sediment records recovered by ANDRILL suggest multiple events of open water conditions and elevated sea surface temperatures at times when terrestrial data from the McMurdo Dry Valleys indicate hyper arid, cold, desert conditions. Interpretation of the ANDRILL data suggests the West Antarctic Ice Sheet is highly sensitive to changes in Pliocene sea surface temperatures and this conclusion has been supported by recent Global Circulation Model results for the early to mid Pliocene. The PIs propose to model paleo-ice configurations and warm orbits associated with a WAIS collapse to assess potential climate change in East Antarctica. During such episodes of polar warmth they propose to answer: What is the limit of ablation along the East Antarctic Ice Sheet?; Are relict landforms in the Dry Valleys susceptible to modification from increase in maximum summertime temperatures?; and Is there sufficient increase in minimum wintertime temperatures to sustain a tundra environment in the Dry Valleys? Integration of depositional records and model outputs have the potential to test the performance of numerical models currently under development as part of ANDRILL; reconcile inconsistencies between marine and terrestrial paleoclimate records in high Southern Latitudes; and improve understanding of Antarctic climate and ice volume sensitivity to forcing for both the East Antarctic and West Antarctic Ice Sheets. Broader impacts: Results from this study have the potential to be used widely by the research community. Outreach to local elementary schools from other funded efforts will continue and be extended to homeschooled students. A Post Doc will be supported as part of this award.\n", "east": -120.0, "geometry": ["POINT(-140 -77.5)"], "keywords": "Antarctica; Atmosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Model Data; Paleoclimate; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -70.0, "nsf_funding_programs": null, "persons": "Kowalewski, Douglas", "project_titles": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "projects": [{"proj_uid": "p0000463", "repository": "USAP-DC", "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "uid": "600140", "west": -160.0}, {"awards": "0732983 Vernet, Maria", "bounds_geometry": ["POLYGON((-66 -62,-65.3 -62,-64.6 -62,-63.9 -62,-63.2 -62,-62.5 -62,-61.8 -62,-61.1 -62,-60.4 -62,-59.7 -62,-59 -62,-59 -62.8,-59 -63.6,-59 -64.4,-59 -65.2,-59 -66,-59 -66.8,-59 -67.6,-59 -68.4,-59 -69.2,-59 -70,-59.7 -70,-60.4 -70,-61.1 -70,-61.8 -70,-62.5 -70,-63.2 -70,-63.9 -70,-64.6 -70,-65.3 -70,-66 -70,-66 -69.2,-66 -68.4,-66 -67.6,-66 -66.8,-66 -66,-66 -65.2,-66 -64.4,-66 -63.6,-66 -62.8,-66 -62))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems. A profound transformation in ecosystem structure and function is occurring in coastal waters of the western Weddell Sea, with the collapse of the Larsen B ice shelf. This transformation appears to be yielding a redistribution of energy flow between chemoautotrophic and photosynthetic production, and to be causing the rapid demise of the extraordinary seep ecosystem discovered beneath the ice shelf. This event provides an ideal opportunity to examine fundamental aspects of ecosystem transition associated with climate change. We propose to test the following hypotheses to elucidate the transformations occurring in marine ecosystems as a consequence of the Larsen B collapse: (1) The biogeographic isolation and sub-ice shelf setting of the Larsen B seep has led to novel habitat characteristics, chemoautotrophically dependent taxa and functional adaptations. (2) Benthic communities beneath the former Larsen B ice shelf are fundamentally different from assemblages at similar depths in the Weddell sea-ice zone, and resemble oligotrophic deep-sea communities. Larsen B assemblages are undergoing rapid change. (3) The previously dark, oligotrophic waters of the Larsen B embayment now support a thriving phototrophic community, with production rates and phytoplankton composition similar to other productive areas of the Weddell Sea. To document rapid changes occurring in the Larsen B ecosystem, we will use a remotely operated vehicle, shipboard samplers, and moored sediment traps. We will characterize microbial, macrofaunal and megafaunal components of the seep community; evaluate patterns of surface productivity, export flux, and benthic faunal composition in areas previously covered by the ice shelf, and compare these areas to the open sea-ice zone. These changes will be placed within the geological, glaciological and climatological context that led to ice-shelf retreat, through companion research projects funded in concert with this effort. Together these projects will help predict the likely consequences of ice-shelf collapse to marine ecosystems in other regions of Antarctica vulnerable to climate change. The research features international collaborators from Argentina, Belgium, Canada, Germany, Spain and the United Kingdom. The broader impacts include participation of a science writer; broadcast of science segments by members of the Jim Lehrer News Hour (Public Broadcasting System); material for summer courses in environmental change; mentoring of graduate students and postdoctoral fellows; and showcasing scientific activities and findings to students and public through podcasts.\n", "east": -59.0, "geometry": ["POINT(-62.5 -66)"], "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biota; LARISSA; Larsen B Ice Shelf; NBP1001; NBP1203; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "locations": "Larsen B Ice Shelf; Southern Ocean; Antarctic Peninsula; Antarctica; Weddell Sea", "north": -62.0, "nsf_funding_programs": null, "persons": "Vernet, Maria", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "projects": [{"proj_uid": "p0000101", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -70.0, "title": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems", "uid": "600073", "west": -66.0}, {"awards": "0732804 McPhee, Miles", "bounds_geometry": ["POINT(166.25 -77.42)"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "The Office of Polar Programs, Antarctic Integrated and System Science Program has made this award to support an interdisciplinary study of the effects of the ocean on the stability of glacial ice in the most dynamic region the West Antarctic Ice Sheet, namely the Pine Island Glacier in the Amundsen Sea Embayment. The collaborative project builds on the knowledge gained by the highly successful West Antarctic Ice Sheet program and is being jointly sponsored with NASA. Recent observations indicate a significant ice loss, equivalent to 10% of the ongoing increase in sea-level rise, in this region. These changes are largest along the coast and propagate rapidly inland, indicating the critical impact of the ocean on ice sheet stability in the region. While a broad range of remote sensing and ground-based instrumentation is available to characterize changes of the ice surface and internal structure (deformation, ice motion, melt) and the shape of the underlying sediment and rock bed, instrumentation has yet to be successfully deployed for observing boundary layer processes of the ocean cavity which underlies the floating ice shelf and where rapid melting is apparently occurring. Innovative, mini ocean sensors that can be lowered through boreholes in the ice shelf (about 500 m thick) will be developed and deployed to automatically provide ocean profiling information over at least three years. Their data will be transmitted through a conducting cable frozen in the borehole to the surface where it will be further transmitted via satellite to a laboratory in the US. Geophysical and remote sensing methods (seismic, GPS, altimetry, stereo imaging, radar profiling) will be applied to map the geometry of the ice shelf, the shape of the sub ice-shelf cavity, the ice surface geometry and deformations within the glacial ice. To integrate the seismic, glaciological and oceanographic observations, a new 3-dimensional coupled ice-ocean model is being developed which will be the first of its kind. NASA is supporting satellite based research and the deployment of a robotic-camera system to explore the environment in the ocean cavity underlying the ice shelf and NSF is supporting all other aspects of this study. \n\nBroader impacts: This project is motivated by the potential societal impacts of rapid sea level rise and should result in critically needed improvements in characterizing and predicting the behavior of coupled ocean-ice systems. It is a contribution to the International Polar Year and was endorsed by the International Council for Science as a component of the \u0027Multidisciplinary Study of the Amundsen Sea Embayment\u0027 proposal #258 of the honeycomb of endorsed IPY activities. The research involves substantial international partnerships with the British Antarctic Survey and the University of Bristol in the UK. The investigators will partner with the previously funded \u0027Polar Palooza\u0027 education and outreach program in addition to undertaking a diverse set of outreach activities of their own. Eight graduate students and one undergraduate as well as one post doc will be integrated into this research project.\n", "east": 166.25, "geometry": ["POINT(166.25 -77.42)"], "keywords": "Antarctica; Atmosphere; McMurdo; Meteorology; Oceans; Ross Island; Southern Ocean", "locations": "McMurdo; Ross Island; Antarctica; Southern Ocean", "north": -77.42, "nsf_funding_programs": null, "persons": "McPhee, Miles G.", "project_titles": "Collaborative Research; IPY: Ocean-Ice Interaction in the Amundsen Sea sector of West Antarctica", "projects": [{"proj_uid": "p0000043", "repository": "USAP-DC", "title": "Collaborative Research; IPY: Ocean-Ice Interaction in the Amundsen Sea sector of West Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.42, "title": "Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica", "uid": "600072", "west": 166.25}, {"awards": "1043690 Scherer, Reed", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material.\nBroader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Diatom; Marine Sediments; Oceans; Sediment Core; Southern Ocean", "locations": "Antarctica; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Haji-Sheikh, Michael; Scherer, Reed Paul", "project_titles": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "projects": [{"proj_uid": "p0000360", "repository": "USAP-DC", "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "uid": "600127", "west": -180.0}, {"awards": "0944475 Kaplan, Michael", "bounds_geometry": ["POLYGON((-180 -84.1,-176.97 -84.1,-173.94 -84.1,-170.91 -84.1,-167.88 -84.1,-164.85 -84.1,-161.82 -84.1,-158.79 -84.1,-155.76 -84.1,-152.73 -84.1,-149.7 -84.1,-149.7 -84.43,-149.7 -84.76,-149.7 -85.09,-149.7 -85.42,-149.7 -85.75,-149.7 -86.08,-149.7 -86.41,-149.7 -86.74,-149.7 -87.07,-149.7 -87.4,-152.73 -87.4,-155.76 -87.4,-158.79 -87.4,-161.82 -87.4,-164.85 -87.4,-167.88 -87.4,-170.91 -87.4,-173.94 -87.4,-176.97 -87.4,180 -87.4,178.12 -87.4,176.24 -87.4,174.36 -87.4,172.48 -87.4,170.6 -87.4,168.72 -87.4,166.84 -87.4,164.96 -87.4,163.08 -87.4,161.2 -87.4,161.2 -87.07,161.2 -86.74,161.2 -86.41,161.2 -86.08,161.2 -85.75,161.2 -85.42,161.2 -85.09,161.2 -84.76,161.2 -84.43,161.2 -84.1,163.08 -84.1,164.96 -84.1,166.84 -84.1,168.72 -84.1,170.6 -84.1,172.48 -84.1,174.36 -84.1,176.24 -84.1,178.12 -84.1,-180 -84.1))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica\u0027s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time.\nBroader Impact: The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": -149.7, "geometry": ["POINT(-174.25 -85.75)"], "keywords": "Antarctica; Cosmogenic Dating; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -84.1, "nsf_funding_programs": null, "persons": "Kaplan, Michael", "project_titles": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "projects": [{"proj_uid": "p0000459", "repository": "USAP-DC", "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "600115", "west": 161.2}, {"awards": "0944489 Williams, Trevor", "bounds_geometry": ["POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Adelie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that indicate ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization. Broader impacts: The data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences\n", "east": 163.0, "geometry": ["POINT(54 -68)"], "keywords": "Geochronology; George V Land; IODP U1356; IODP U1361; Marine Sediments; ODP1165; Prydz Bay; Solid Earth; Southern Ocean; Wilkes Land", "locations": "Southern Ocean; George V Land; Prydz Bay; Wilkes Land", "north": -58.0, "nsf_funding_programs": null, "persons": "Williams, Trevor; Hemming, Sidney R.", "project_titles": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "projects": [{"proj_uid": "p0000353", "repository": "USAP-DC", "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "uid": "600116", "west": -55.0}, {"awards": "1039365 Rimmer, Susan", "bounds_geometry": null, "date_created": "Tue, 01 Jan 2013 00:00:00 GMT", "description": "This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. The broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming.\n", "east": null, "geometry": null, "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": null, "nsf_funding_programs": null, "persons": "Rimmer, Susan", "project_titles": "Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter", "projects": [{"proj_uid": "p0000507", "repository": "USAP-DC", "title": "Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "uid": "600121", "west": null}, {"awards": "0739698 Doran, Peter; 0739681 Murray, Alison", "bounds_geometry": ["POINT(161.931 -77.3885)"], "date_created": "Tue, 01 Jan 2013 00:00:00 GMT", "description": "Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake\u0027s history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities.", "east": 161.931, "geometry": ["POINT(161.931 -77.3885)"], "keywords": "Antarctica; Biota; Carbon-14; Chemistry:fluid; Chemistry:Fluid; Chemistry:ice; Chemistry:Ice; Dry Valleys; Geochronology; Ice Core Records; Lake Vida; Microbiology", "locations": "Dry Valleys; Lake Vida; Antarctica", "north": -77.3885, "nsf_funding_programs": null, "persons": "Murray, Alison", "project_titles": "Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "projects": [{"proj_uid": "p0000485", "repository": "USAP-DC", "title": "Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.3885, "title": "Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "uid": "600080", "west": 161.931}, {"awards": "0838722 Reiners, Peter", "bounds_geometry": ["POLYGON((61.9 -67.28,63.218 -67.28,64.536 -67.28,65.854 -67.28,67.172 -67.28,68.49 -67.28,69.808 -67.28,71.126 -67.28,72.444 -67.28,73.762 -67.28,75.08 -67.28,75.08 -67.922,75.08 -68.564,75.08 -69.206,75.08 -69.848,75.08 -70.49,75.08 -71.132,75.08 -71.774,75.08 -72.416,75.08 -73.058,75.08 -73.7,73.762 -73.7,72.444 -73.7,71.126 -73.7,69.808 -73.7,68.49 -73.7,67.172 -73.7,65.854 -73.7,64.536 -73.7,63.218 -73.7,61.9 -73.7,61.9 -73.058,61.9 -72.416,61.9 -71.774,61.9 -71.132,61.9 -70.49,61.9 -69.848,61.9 -69.206,61.9 -68.564,61.9 -67.922,61.9 -67.28))"], "date_created": "Sun, 01 Jan 2012 00:00:00 GMT", "description": "Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion.\n", "east": 75.08, "geometry": ["POINT(68.49 -70.49)"], "keywords": "Antarctica; Fission Track Thermochronology; Gamburtsev Mountains; Geochronology; Marine Sediments; NBP0101; ODP1166; ODP739; Prydz Bay; Solid Earth; Southern Ocean", "locations": "Prydz Bay; Southern Ocean; Antarctica; Gamburtsev Mountains", "north": -67.28, "nsf_funding_programs": null, "persons": "Gehrels, George; Reiners, Peter; Thomson, Stuart", "project_titles": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "projects": [{"proj_uid": "p0000506", "repository": "USAP-DC", "title": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -73.7, "title": "Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "uid": "600093", "west": 61.9}, {"awards": "0739781 Blythe, Ann", "bounds_geometry": ["POLYGON((155.77667 -79.793335,156.208836 -79.793335,156.641002 -79.793335,157.073168 -79.793335,157.505334 -79.793335,157.9375 -79.793335,158.369666 -79.793335,158.801832 -79.793335,159.233998 -79.793335,159.666164 -79.793335,160.09833 -79.793335,160.09833 -79.8578345,160.09833 -79.922334,160.09833 -79.9868335,160.09833 -80.051333,160.09833 -80.1158325,160.09833 -80.180332,160.09833 -80.2448315,160.09833 -80.309331,160.09833 -80.3738305,160.09833 -80.43833,159.666164 -80.43833,159.233998 -80.43833,158.801832 -80.43833,158.369666 -80.43833,157.9375 -80.43833,157.505334 -80.43833,157.073168 -80.43833,156.641002 -80.43833,156.208836 -80.43833,155.77667 -80.43833,155.77667 -80.3738305,155.77667 -80.309331,155.77667 -80.2448315,155.77667 -80.180332,155.77667 -80.1158325,155.77667 -80.051333,155.77667 -79.9868335,155.77667 -79.922334,155.77667 -79.8578345,155.77667 -79.793335))"], "date_created": "Sun, 01 Jan 2012 00:00:00 GMT", "description": "This project studies formation of the TransAntarctic Mountains (TAM) through numerical modeling based on cooling histories of apatite mineral grains. The TAM are the highest and longest rift-related mountain range in the world. Various models for their uplift have been proposed, the most provocative of which is that they are not uplifted, but instead are the eroded remnant of a plateau. This project evaluates that hypothesis by collecting apatites from around Byrd Glacier for fission track thermochronology. Results will be combined with a kinematic and thermal model to determine the TAM\u0027s structural evolution. The plateau model, if correct, implies that the Byrd Glacier originated not as a glacier-carved valley through the TAM, but as a river system flowing in the opposite direction. Given that the Byrd Glacier is a key drainage for the East Antarctic ice sheet, this result has important implications for ice sheet models and interpretation of both regional geology and sediment records. The main broader impacts are undergraduate research and a new collaboration between a primarily undergraduate and a research institution. Students will be involved in the field program, sample analyses, and numerical modeling.", "east": 160.09833, "geometry": ["POINT(157.9375 -80.1158325)"], "keywords": "Antarctica; Fission Track Thermochronology; Geochemistry; Solid Earth; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -79.793335, "nsf_funding_programs": null, "persons": "Blythe, Ann Elizabeth; Huerta, Audrey D.", "project_titles": "Collaborative Research: Thermochronologic and modelling test for a Mesozoic West Antarctic Plateau", "projects": [{"proj_uid": "p0000677", "repository": "USAP-DC", "title": "Collaborative Research: Thermochronologic and modelling test for a Mesozoic West Antarctic Plateau"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.43833, "title": "Thermochronologic and modelling test for a Mesozoic West Antarctic Plateau", "uid": "600082", "west": 155.77667}, {"awards": "0838729 Hemming, Sidney", "bounds_geometry": ["POLYGON((-67.2 -58,-43.98 -58,-20.76 -58,2.46 -58,25.68 -58,48.9 -58,72.12 -58,95.34 -58,118.56 -58,141.78 -58,165 -58,165 -59.2,165 -60.4,165 -61.6,165 -62.8,165 -64,165 -65.2,165 -66.4,165 -67.6,165 -68.8,165 -70,141.78 -70,118.56 -70,95.34 -70,72.12 -70,48.9 -70,25.68 -70,2.46 -70,-20.76 -70,-43.98 -70,-67.2 -70,-67.2 -68.8,-67.2 -67.6,-67.2 -66.4,-67.2 -65.2,-67.2 -64,-67.2 -62.8,-67.2 -61.6,-67.2 -60.4,-67.2 -59.2,-67.2 -58))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion.", "east": 165.0, "geometry": ["POINT(48.9 -64)"], "keywords": "Antarctica; Fission Track Thermochronology; Gamburtsev Mountains; Geochronology; Marine Sediments; Solid Earth; Southern Ocean", "locations": "Gamburtsev Mountains; Antarctica; Southern Ocean", "north": -58.0, "nsf_funding_programs": null, "persons": "Hemming, Sidney R.", "project_titles": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "projects": [{"proj_uid": "p0000506", "repository": "USAP-DC", "title": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "uid": "600094", "west": -67.2}, {"awards": "0902957 Robinson, Laura", "bounds_geometry": ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project\u0027s goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth\u0027s system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.", "east": -35.0, "geometry": ["POINT(-52.75 -58)"], "keywords": "Biota; Corals; Drake Passage; Geochronology; NBP0805; Oceans; Paleoclimate; Radiocarbon; Southern Ocean", "locations": "Drake Passage; Southern Ocean", "north": -54.5, "nsf_funding_programs": null, "persons": "Robinson, Laura", "project_titles": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "projects": [{"proj_uid": "p0000519", "repository": "USAP-DC", "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.5, "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "uid": "600111", "west": -70.5}, {"awards": "0842639 Soreghan, Gerilyn", "bounds_geometry": ["POLYGON((-163.12865 -77.41693,-163.06062 -77.41693,-162.99259 -77.41693,-162.92456 -77.41693,-162.85653 -77.41693,-162.7885 -77.41693,-162.72047 -77.41693,-162.65244 -77.41693,-162.58441 -77.41693,-162.51638 -77.41693,-162.44835 -77.41693,-162.44835 -77.445495,-162.44835 -77.47406,-162.44835 -77.502625,-162.44835 -77.53119,-162.44835 -77.559755,-162.44835 -77.58832,-162.44835 -77.616885,-162.44835 -77.64545,-162.44835 -77.674015,-162.44835 -77.70258,-162.51638 -77.70258,-162.58441 -77.70258,-162.65244 -77.70258,-162.72047 -77.70258,-162.7885 -77.70258,-162.85653 -77.70258,-162.92456 -77.70258,-162.99259 -77.70258,-163.06062 -77.70258,-163.12865 -77.70258,-163.12865 -77.674015,-163.12865 -77.64545,-163.12865 -77.616885,-163.12865 -77.58832,-163.12865 -77.559755,-163.12865 -77.53119,-163.12865 -77.502625,-163.12865 -77.47406,-163.12865 -77.445495,-163.12865 -77.41693))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "The proposed research seeks to test the hypothesis that chemical and physical weathering in proximal alluvial systems will show systematic and measurable variations between glacial and nonglacial systems. To accomplish this, the investigation will attempt to quantify the natural variation of chemical and physical weathering in granitoid-sourced proximal alluvial sediments in end-member glacial and nonglacial systems, when other, \u0027non-climatic\u0027 factors (e.g. provenance, drainage basin area and relief, sample grain size, sediment facies) are controlled. If chemical weathering in the proposed hot-humid, hot-arid, hot semi-arid nonglacial systems and the cool-wet, cold semi-arid, and cold-arid glacial systems show systematic variations, then chemical indices may be used to help differentiate paleoclimatic conditions. Continued reliance on students provides a broader impact of this proposed research and firmly grounds this effort in its educational mission.", "east": -162.44835, "geometry": ["POINT(-162.7885 -77.559755)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Chemistry:rock; Chemistry:Rock; Chemistry:sediment; Chemistry:Sediment; Critical Zone; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet", "locations": "Antarctica", "north": -77.41693, "nsf_funding_programs": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "project_titles": "Development of Quantitative Weathering Indicators in Proximal Alluvial Sediments to Assess Glacial Activity in the Rock Record", "projects": [{"proj_uid": "p0000518", "repository": "USAP-DC", "title": "Development of Quantitative Weathering Indicators in Proximal Alluvial Sediments to Assess Glacial Activity in the Rock Record"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.70258, "title": "Development of Quantitative Weathering Indicators in Proximal Alluvial Sediments to Assess Glacial Activity in the Rock Record", "uid": "600110", "west": -163.12865}, {"awards": "0636319 Shaw, Timothy", "bounds_geometry": ["POLYGON((-51.9201 -57.5061,-50.99447 -57.5061,-50.06884 -57.5061,-49.14321 -57.5061,-48.21758 -57.5061,-47.29195 -57.5061,-46.36632 -57.5061,-45.44069 -57.5061,-44.51506 -57.5061,-43.58943 -57.5061,-42.6638 -57.5061,-42.6638 -58.03449,-42.6638 -58.56288,-42.6638 -59.09127,-42.6638 -59.61966,-42.6638 -60.14805,-42.6638 -60.67644,-42.6638 -61.20483,-42.6638 -61.73322,-42.6638 -62.26161,-42.6638 -62.79,-43.58943 -62.79,-44.51506 -62.79,-45.44069 -62.79,-46.36632 -62.79,-47.29195 -62.79,-48.21758 -62.79,-49.14321 -62.79,-50.06884 -62.79,-50.99447 -62.79,-51.9201 -62.79,-51.9201 -62.26161,-51.9201 -61.73322,-51.9201 -61.20483,-51.9201 -60.67644,-51.9201 -60.14805,-51.9201 -59.61966,-51.9201 -59.09127,-51.9201 -58.56288,-51.9201 -58.03449,-51.9201 -57.5061))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.", "east": -42.6638, "geometry": ["POINT(-47.29195 -60.14805)"], "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Oceans; Sea Ice; Sea Surface; Southern Ocean; Weddell Sea", "locations": "Weddell Sea; Sea Surface; Southern Ocean", "north": -57.5061, "nsf_funding_programs": null, "persons": "Shaw, Tim; Twining, Benjamin", "project_titles": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "projects": [{"proj_uid": "p0000511", "repository": "USAP-DC", "title": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -62.79, "title": "Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "uid": "600064", "west": -51.9201}, {"awards": "0636543 Murray, Alison", "bounds_geometry": ["POLYGON((-51.98403 -57.58068,-51.042765 -57.58068,-50.1015 -57.58068,-49.160235 -57.58068,-48.21897 -57.58068,-47.277705 -57.58068,-46.33644 -57.58068,-45.395175 -57.58068,-44.45391 -57.58068,-43.512645 -57.58068,-42.57138 -57.58068,-42.57138 -58.10845,-42.57138 -58.63622,-42.57138 -59.16399,-42.57138 -59.69176,-42.57138 -60.21953,-42.57138 -60.7473,-42.57138 -61.27507,-42.57138 -61.80284,-42.57138 -62.33061,-42.57138 -62.85838,-43.512645 -62.85838,-44.45391 -62.85838,-45.395175 -62.85838,-46.33644 -62.85838,-47.277705 -62.85838,-48.21897 -62.85838,-49.160235 -62.85838,-50.1015 -62.85838,-51.042765 -62.85838,-51.98403 -62.85838,-51.98403 -62.33061,-51.98403 -61.80284,-51.98403 -61.27507,-51.98403 -60.7473,-51.98403 -60.21953,-51.98403 -59.69176,-51.98403 -59.16399,-51.98403 -58.63622,-51.98403 -58.10845,-51.98403 -57.58068))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.", "east": -42.57138, "geometry": ["POINT(-47.277705 -60.21953)"], "keywords": "Biota; Geochemistry; NBP0902; Oceans; Physical Oceanography; Sea Ice; Southern Ocean; Weddell Sea", "locations": "Southern Ocean; Weddell Sea", "north": -57.58068, "nsf_funding_programs": null, "persons": "Murray, Alison", "project_titles": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "projects": [{"proj_uid": "p0000511", "repository": "USAP-DC", "title": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -62.85838, "title": "Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "uid": "600065", "west": -51.98403}, {"awards": "0538580 Hemming, Sidney", "bounds_geometry": ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "This project studies sediment from the ocean floor to understand Antarctica\u0027s geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work\u0027s central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry.", "east": 180.0, "geometry": ["POINT(120 -65)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Geochronology; Isotope Data; Marine Sediments; Oceans; Prydz Bay; Solid Earth; Southern Ocean; Weddell Sea; Wilkes Land", "locations": "Antarctica; Weddell Sea; Prydz Bay; Wilkes Land; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R.", "project_titles": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "projects": [{"proj_uid": "p0000524", "repository": "USAP-DC", "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "uid": "600056", "west": 60.0}, {"awards": "0338163 Leventer, Amy", "bounds_geometry": ["POLYGON((-70.90391 -52.35262,-68.130917 -52.35262,-65.357924 -52.35262,-62.584931 -52.35262,-59.811938 -52.35262,-57.038945 -52.35262,-54.265952 -52.35262,-51.492959 -52.35262,-48.719966 -52.35262,-45.946973 -52.35262,-43.17398 -52.35262,-43.17398 -53.75776,-43.17398 -55.1629,-43.17398 -56.56804,-43.17398 -57.97318,-43.17398 -59.37832,-43.17398 -60.78346,-43.17398 -62.1886,-43.17398 -63.59374,-43.17398 -64.99888,-43.17398 -66.40402,-45.946973 -66.40402,-48.719966 -66.40402,-51.492959 -66.40402,-54.265952 -66.40402,-57.038945 -66.40402,-59.811938 -66.40402,-62.584931 -66.40402,-65.357924 -66.40402,-68.130917 -66.40402,-70.90391 -66.40402,-70.90391 -64.99888,-70.90391 -63.59374,-70.90391 -62.1886,-70.90391 -60.78346,-70.90391 -59.37832,-70.90391 -57.97318,-70.90391 -56.56804,-70.90391 -55.1629,-70.90391 -53.75776,-70.90391 -52.35262))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "The NSF-supported research icebreaker Nathaniel B. Palmer operates year-round in support of the U.S. Antarctic Program, carrying out global change studies in biological, chemical, physical, and oceanographic disciplines. \n This data set consists of underway data from leg NBP0603 on the R/V Nathaniel B. Palmer. This leg started at Punta Arenas, Chile and ended at Punta Arenas, Chile.", "east": -43.17398, "geometry": ["POINT(-57.038945 -59.37832)"], "keywords": "ADCP Acoustic Doppler Current Profiler; Antarctic Peninsula; Biota; Diatom; Electromagnetic Data; Flask Glacier; Foehn Winds; Larsen Ice Shelf; Marine Sediments; NBP0603; Oceans; Physical Ice Properties; R/v Nathaniel B. Palmer; Scar Inlet; Southern Ocean", "locations": "Larsen Ice Shelf; Southern Ocean; Flask Glacier; Scar Inlet; Antarctic Peninsula", "north": -52.35262, "nsf_funding_programs": null, "persons": "Domack, Eugene Walter", "project_titles": "Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II", "projects": [{"proj_uid": "p0000215", "repository": "USAP-DC", "title": "Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.40402, "title": "R/V Nathaniel B. Palmer NBP0603 - Paleohistory of the Larsen Ice Shelf System", "uid": "600027", "west": -70.90391}, {"awards": "0338087 Scheltema, Rudolf", "bounds_geometry": ["POLYGON((-70 -53,-68.4 -53,-66.8 -53,-65.2 -53,-63.6 -53,-62 -53,-60.4 -53,-58.8 -53,-57.2 -53,-55.6 -53,-54 -53,-54 -54.5,-54 -56,-54 -57.5,-54 -59,-54 -60.5,-54 -62,-54 -63.5,-54 -65,-54 -66.5,-54 -68,-55.6 -68,-57.2 -68,-58.8 -68,-60.4 -68,-62 -68,-63.6 -68,-65.2 -68,-66.8 -68,-68.4 -68,-70 -68,-70 -66.5,-70 -65,-70 -63.5,-70 -62,-70 -60.5,-70 -59,-70 -57.5,-70 -56,-70 -54.5,-70 -53))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "Because of extreme isolation of the Antarctic continent since the Early Oligocene, one expects a unique invertebrate benthic fauna with a high degree of endemism. Yet some invertebrate taxa that constitute important ecological components of sedimentary benthic communities include more than 40 percent non-endemic species (e.g., benthic polychaetes). To account for non-endemic species, intermittent genetic exchange must occur between Antarctic and other (e.g. South American) populations. The most likely mechanism for such gene flow, at least for in-faunal and mobile macrobenthos, is dispersal of planktonic larvae across the sub- Antarctic and Antarctic polar fronts. To test for larval dispersal as a mechanism of maintaining genetic continuity across polar fronts, the scientists propose to (1) take plankton samples along transects across Drake passage during both the austral summer and winter seasons while concurrently collecting the appropriate hydrographic data. Such data will help elucidate the hydrographic mechanisms that allow dispersal across Drake Passage. Using a molecular phylogenetic approach, they will (2) compare seemingly identical adult forms from Antarctic and South America continents to identify genetic breaks, historical gene flow, and control for the presence of cryptic species. (3) Similar molecular tools will be used to relate planktonic larvae to their adult forms. Through this procedure, they propose to link the larval forms respectively to their Antarctic or South America origins. The proposed work builds on previous research that provides the basis for this effort to develop a synthetic understanding of historical gene flow and present day dispersal mechanism in South American/Drake Passage/Antarctic Peninsular region. Furthermore, this work represents one of the first attempts to examine recent gene flow in Antarctic benthic invertebrates. Graduate students and a postdoctoral fellow will be trained during this research.", "east": -54.0, "geometry": ["POINT(-62 -60.5)"], "keywords": "Antarctica; Biota; Oceans; R/v Laurence M. Gould; Sample/collection Description; Sample/Collection Description; Southern Ocean", "locations": "Southern Ocean; Antarctica", "north": -53.0, "nsf_funding_programs": null, "persons": "Scheltema, Rudolf", "project_titles": "Collaborative Research: Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates", "projects": [{"proj_uid": "p0000189", "repository": "USAP-DC", "title": "Collaborative Research: Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -68.0, "title": "Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates", "uid": "600035", "west": -70.0}, {"awards": "0439906 Koch, Paul", "bounds_geometry": ["POLYGON((162 -72,162.6 -72,163.2 -72,163.8 -72,164.4 -72,165 -72,165.6 -72,166.2 -72,166.8 -72,167.4 -72,168 -72,168 -72.6,168 -73.2,168 -73.8,168 -74.4,168 -75,168 -75.6,168 -76.2,168 -76.8,168 -77.4,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "During previous NSF-sponsored research, the PI\u0027s discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island. This project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses.\n\nBecause of extreme isolation of the Antarctic continent since the \nEarly Oligocene, one expects a unique invertebrate benthic fauna with \na high degree of endemism. Yet some invertebrate taxa that constitute \nimportant ecological components of sedimentary benthic communities \ninclude more than 40 percent non-endemic species (e.g., benthic \npolychaetes). To account for non-endemic species, intermittent genetic \nexchange must occur between Antarctic and other (e.g. South American) \npopulations. The most likely mechanism for such gene flow, at least \nfor in-faunal and mobile macrobenthos, is dispersal of planktonic \nlarvae across the sub- Antarctic and Antarctic polar fronts. To test \nfor larval dispersal as a mechanism of maintaining genetic continuity \nacross polar fronts, the scientists propose to (1) take plankton \nsamples along transects across Drake passage during both the austral \nsummer and winter seasons while concurrently collecting the \nappropriate hydrographic data. Such data will help elucidate the \nhydrographic mechanisms that allow dispersal across Drake Passage. \nUsing a molecular phylogenetic approach, they will (2) compare \nseemingly identical adult forms from Antarctic and South America \ncontinents to identify genetic breaks, historical gene flow, and \ncontrol for the presence of cryptic species. (3) Similar molecular \ntools will be used to relate planktonic larvae to their adult forms. \nThrough this procedure, they propose to link the larval forms \nrespectively to their Antarctic or South America origins. The proposed \nwork builds on previous research that provides the basis for this \neffort to develop a synthetic understanding of historical gene flow \nand present day dispersal mechanism in South American/Drake Passage/ \nAntarctic Peninsular region. Furthermore, this work represents one of \nthe first attempts to examine recent gene flow in Antarctic benthic \ninvertebrates. Graduate students and a postdoctoral fellow will be \ntrained during this research\n", "east": 168.0, "geometry": ["POINT(165 -75)"], "keywords": "Biota; Isotope; Penguin; Ross Sea; Seals; Southern Ocean", "locations": "Southern Ocean; Ross Sea", "north": -72.0, "nsf_funding_programs": null, "persons": "Koch, Paul", "project_titles": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "projects": [{"proj_uid": "p0000533", "repository": "USAP-DC", "title": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "uid": "600041", "west": 162.0}, {"awards": "0636730 Vernet, Maria", "bounds_geometry": ["POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.\n", "east": -40.0, "geometry": ["POINT(-47.5 -58.5)"], "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; NBP0902; Oceans; Physical Oceanography; Sea Surface; Southern Ocean; Weddell Sea", "locations": "Sea Surface; Antarctica; Southern Ocean; Weddell Sea", "north": -52.0, "nsf_funding_programs": null, "persons": "Vernet, Maria", "project_titles": "Collaborative Reseach: Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean.", "projects": [{"proj_uid": "p0000532", "repository": "USAP-DC", "title": "Collaborative Reseach: Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "uid": "600068", "west": -55.0}, {"awards": "0636723 Helly, John", "bounds_geometry": ["POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.", "east": -40.0, "geometry": ["POINT(-47.5 -58.5)"], "keywords": "Antarctica; NBP0902; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "locations": "Antarctica; Southern Ocean; Weddell Sea", "north": -52.0, "nsf_funding_programs": null, "persons": "Helly, John", "project_titles": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "projects": [{"proj_uid": "p0000511", "repository": "USAP-DC", "title": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "uid": "600067", "west": -55.0}, {"awards": "0228842 Grew, Edward", "bounds_geometry": ["POLYGON((76 -69.3,76.05 -69.3,76.1 -69.3,76.15 -69.3,76.2 -69.3,76.25 -69.3,76.3 -69.3,76.35 -69.3,76.4 -69.3,76.45 -69.3,76.5 -69.3,76.5 -69.32,76.5 -69.34,76.5 -69.36,76.5 -69.38,76.5 -69.4,76.5 -69.42,76.5 -69.44,76.5 -69.46,76.5 -69.48,76.5 -69.5,76.45 -69.5,76.4 -69.5,76.35 -69.5,76.3 -69.5,76.25 -69.5,76.2 -69.5,76.15 -69.5,76.1 -69.5,76.05 -69.5,76 -69.5,76 -69.48,76 -69.46,76 -69.44,76 -69.42,76 -69.4,76 -69.38,76 -69.36,76 -69.34,76 -69.32,76 -69.3))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts per million in rocks subjected to conditions of the middle and lower crust, that is, temperatures of 700 degrees C or more in the granulite-facies, which is characterized by very low water activities at pressures of 5 to 10 kbar (18-35 km burial). Devolatization reactions with loss of aqueous fluid and partial melting with removal of melt have been cited as primary causes for boron depletion under granulite-facies conditions. Despite the pervasiveness of both these processes, rocks rich in boron are locally found in the granulite-facies, that is, there are mechanisms for retaining boron during the metamorphic process. The Larsemann Hills, Prydz Bay, Antarctica, are a prime example. More than 20 lenses and layered bodies containing four borosilicate mineral species crop out over a 50 square kilometer area, which thus would be well suited for research on boron-rich granulite-facies metamorphic rocks. While most investigators have focused on the causes for loss of boron, this work will investigate how boron is retained during high-grade metamorphism. Field observations and mapping in the Larsemann Hills, chemical analyses of minerals and their host rocks, and microprobe age dating will be used to identify possible precursors and deduce how the precursor materials recrystallized into borosilicate rocks under granulite-facies conditions. \n\nThe working hypothesis is that high initial boron content facilitates retention of boron during metamorphism because above a certain threshold boron content, a mechanism \u0027kicks in\u0027 that facilitates retention of boron in metamorphosed rocks. For example, in a rock with large amounts of the borosilicate tourmaline, such as stratabound tourmalinite, the breakdown of tourmaline to melt could result in the formation of prismatine and grandidierite, two borosilicates found in the Larsemann Hills. This situation is rarely observed in rocks with modest boron content, in which breakdown of tourmaline releases boron into partial melts, which in turn remove boron when they leave the system. Stratabound tourmalinite is associated with manganese-rich quartzite, phosphorus-rich rocks and sulfide concentrations that could be diagnostic for recognizing a tourmalinite protolith in a highly metamorphosed complex where sedimentary features have been destroyed by deformation. Because partial melting plays an important role in the fate of boron during metamorphism, our field and laboratory research will focus on the relationship between the borosilicate units, granite pegmatites and other granitic intrusives. The results of our study will provide information on cycling of boron at deeper levels in the Earth\u0027s crust and on possible sources of boron for granites originating from deep-seated rocks. An undergraduate student will participate in the electron microprobe age-dating of monazite and xenotime as part of a senior project, thereby integrating the proposed research into the educational mission of the University of Maine. In response to a proposal for fieldwork, the Australian Antarctic Division, which maintains Davis station near the Larsemann Hills, has indicated that they will support the Antarctic fieldwork.", "east": 76.5, "geometry": ["POINT(76.25 -69.4)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Geochronology; Solid Earth", "locations": "Antarctica", "north": -69.3, "nsf_funding_programs": null, "persons": "Grew, Edward", "project_titles": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "projects": [{"proj_uid": "p0000431", "repository": "USAP-DC", "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.5, "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "uid": "600030", "west": 76.0}, {"awards": "0125098 Emslie, Steven", "bounds_geometry": ["POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. \n\nOther data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC.", "east": 160.0, "geometry": ["POINT(55 -75)"], "keywords": "Antarctica; Biota; Geochronology; Oceans; Paleoclimate; Penguin; Radiocarbon; Ross Sea; Southern Ocean", "locations": "Ross Sea; Southern Ocean; Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Emslie, Steven", "project_titles": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "projects": [{"proj_uid": "p0000220", "repository": "USAP-DC", "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "uid": "600028", "west": -50.0}, {"awards": "0440954 Miller, Molly", "bounds_geometry": ["POLYGON((159 -76.61667,159.05 -76.61667,159.1 -76.61667,159.15 -76.61667,159.2 -76.61667,159.25 -76.61667,159.3 -76.61667,159.35 -76.61667,159.4 -76.61667,159.45 -76.61667,159.5 -76.61667,159.5 -76.630003,159.5 -76.643336,159.5 -76.656669,159.5 -76.670002,159.5 -76.683335,159.5 -76.696668,159.5 -76.710001,159.5 -76.723334,159.5 -76.736667,159.5 -76.75,159.45 -76.75,159.4 -76.75,159.35 -76.75,159.3 -76.75,159.25 -76.75,159.2 -76.75,159.15 -76.75,159.1 -76.75,159.05 -76.75,159 -76.75,159 -76.736667,159 -76.723334,159 -76.710001,159 -76.696668,159 -76.683335,159 -76.670002,159 -76.656669,159 -76.643336,159 -76.630003,159 -76.61667))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate. In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.", "east": 159.5, "geometry": ["POINT(159.25 -76.683335)"], "keywords": "Allan Hills; Antarctica; Paleontology; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Allan Hills; Antarctica", "north": -76.61667, "nsf_funding_programs": null, "persons": "Miller, Molly", "project_titles": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "projects": [{"proj_uid": "p0000207", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.75, "title": "Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "uid": "600045", "west": 159.0}, {"awards": "0538195 Marone, Chris", "bounds_geometry": null, "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This award supports a project to conduct laboratory experiments and numerical modeling to determine the constitutive properties of subglacial till under dynamic stressing and to test the hypothesis that granular properties of till are sufficient, when coupled elastically to a large ice stream, to reproduce the field observations of triggered slip and subglacial seismicity. Testing will be carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, which will allow both sliding and microstructural processes to be studied in detail. The main focus of the work will be on laboratory measurements. In addition, we will construct continuum models to evaluate whether our results can predict complex ice sheet motions and observed characteristics of subglacial seismicity. In terms of broader impacts, the proposed work will encourage interactions between the rock-mechanics and glaciology communities and will bring together members of different scientific backgrounds and vocabularies, but similar problems and data. The project will train undergraduate and graduate students at Penn State University and the scientists involved plan to give presentations to grade school classes, scout groups, and at community open houses. Results will be presented at professional meetings and will be published in a timely manner. The work will result in a better understanding of glacial motion and the physics of earthquake slip, which is essential for understanding ice sheet dynamics and earthquake hazard.", "east": null, "geometry": null, "keywords": "Antarctica; Glacial Till; Glaciers/ice Sheet; Glaciers/Ice Sheet; Lab Experiment; Marine Sediments; Physical Properties; Solid Earth", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "persons": "Marone, Chris; Anandakrishnan, Sridhar", "project_titles": "Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till", "projects": [{"proj_uid": "p0000554", "repository": "USAP-DC", "title": "Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till", "uid": "600054", "west": null}, {"awards": "0739452 Mukhopadhyay, Sujoy", "bounds_geometry": ["POLYGON((161 -76,161.2 -76,161.4 -76,161.6 -76,161.8 -76,162 -76,162.2 -76,162.4 -76,162.6 -76,162.8 -76,163 -76,163 -76.2,163 -76.4,163 -76.6,163 -76.8,163 -77,163 -77.2,163 -77.4,163 -77.6,163 -77.8,163 -78,162.8 -78,162.6 -78,162.4 -78,162.2 -78,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project seeks to answer a simple question: how old are potholes and related geomorphic features found in the uplands of the McMurdo Dry Valleys, Antarctica? Some research suggests that they are over ten million years old and date the growth of the East Antarctic Ice Sheet, the world\u0027s largest. However, some evidence suggests that these are young, erosional features that continuing to evolve to this day. This project uses cosmogenic nuclide dating to determine the age of the pothole floors. The results are important for determining the ice sheet?s history and interpreting the O-isotope record from the marine sediment cores, key records of global climate. Broader impacts include K12 outreach and incorporation of outcomes into university courses.", "east": 163.0, "geometry": ["POINT(162 -77)"], "keywords": "Antarctica; Cosmogenic Dating; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Paleoclimate; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Dry Valleys; Antarctica", "north": -76.0, "nsf_funding_programs": null, "persons": "Mukhopadhyay, Sujoy", "project_titles": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "projects": [{"proj_uid": "p0000461", "repository": "USAP-DC", "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "uid": "600074", "west": 161.0}, {"awards": "0739496 Miller, Molly", "bounds_geometry": ["POLYGON((163.41667 -77.33333,163.46667 -77.33333,163.51667 -77.33333,163.56667 -77.33333,163.61667 -77.33333,163.66667 -77.33333,163.71667 -77.33333,163.76667 -77.33333,163.81667 -77.33333,163.86667 -77.33333,163.91667 -77.33333,163.91667 -77.369997,163.91667 -77.406664,163.91667 -77.443331,163.91667 -77.479998,163.91667 -77.516665,163.91667 -77.553332,163.91667 -77.589999,163.91667 -77.626666,163.91667 -77.663333,163.91667 -77.7,163.86667 -77.7,163.81667 -77.7,163.76667 -77.7,163.71667 -77.7,163.66667 -77.7,163.61667 -77.7,163.56667 -77.7,163.51667 -77.7,163.46667 -77.7,163.41667 -77.7,163.41667 -77.663333,163.41667 -77.626666,163.41667 -77.589999,163.41667 -77.553332,163.41667 -77.516665,163.41667 -77.479998,163.41667 -77.443331,163.41667 -77.406664,163.41667 -77.369997,163.41667 -77.33333))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project answers a simple question: why are there so few fossils in sediment cores from Antarctica\u0027s continental shelf? Antarctica\u0027s benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change.", "east": 163.91667, "geometry": ["POINT(163.66667 -77.516665)"], "keywords": "Biota; Geochronology; Marine Sediments; Oceans; Southern Ocean", "locations": "Southern Ocean", "north": -77.33333, "nsf_funding_programs": null, "persons": "Furbish, David; Miller, Molly", "project_titles": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "projects": [{"proj_uid": "p0000203", "repository": "USAP-DC", "title": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.7, "title": "Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "uid": "600076", "west": 163.41667}, {"awards": "0739512 Walker, Sally", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project answers a simple question: why are there so few fossils in sediment cores from Antarctica\u0027s continental shelf? Antarctica\u0027s benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Glaciers/ice Sheet; Glaciers/Ice Sheet; McMurdo Sound; Oceans; Sample/collection Description; Sample/Collection Description", "locations": "McMurdo Sound; Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Walker, Sally", "project_titles": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores; Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past", "projects": [{"proj_uid": "p0010238", "repository": "USAP-DC", "title": "Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past"}, {"proj_uid": "p0000203", "repository": "USAP-DC", "title": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "uid": "600077", "west": -180.0}, {"awards": "0739693 Ashworth, Allan", "bounds_geometry": ["POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia. In terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica\u0027s ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise.", "east": 162.0, "geometry": ["POINT(161 -77.5)"], "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; GPS; Solid Earth", "locations": "Antarctica", "north": -77.0, "nsf_funding_programs": null, "persons": "Ashworth, Allan; Lewis, Adam", "project_titles": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "projects": [{"proj_uid": "p0000188", "repository": "USAP-DC", "title": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "uid": "600081", "west": 160.0}, {"awards": "0817163 Reiners, Peter", "bounds_geometry": ["POLYGON((72 -66,72.3 -66,72.6 -66,72.9 -66,73.2 -66,73.5 -66,73.8 -66,74.1 -66,74.4 -66,74.7 -66,75 -66,75 -66.3,75 -66.6,75 -66.9,75 -67.2,75 -67.5,75 -67.8,75 -68.1,75 -68.4,75 -68.7,75 -69,74.7 -69,74.4 -69,74.1 -69,73.8 -69,73.5 -69,73.2 -69,72.9 -69,72.6 -69,72.3 -69,72 -69,72 -68.7,72 -68.4,72 -68.1,72 -67.8,72 -67.5,72 -67.2,72 -66.9,72 -66.6,72 -66.3,72 -66))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This Small Grant for Exploratory Research investigates the origin and evolution of the Gamburtsev subglacial mountains (GSM). These mountains are considered the nucleation point for Antarctica\u0027s largest ice sheets; however, being of indeterminate age, they may postdate ice sheet formation. As well, their formation could reflect tectonic events during the breakup of Gondwana. The project studies GSM-derived detrital zircon and apatite crystals from Prydz Bay obtained by the Ocean Drilling Program. Analytical work includes triple-dating thermochronometry by U/Pb, fission track, and (U/Th)/He methods. The combined technique offers insight into both high and low temperature processes, and is potentially sensitive to both the orogenic events and the subsequent cooling and exhumation due to erosion. In terms of broader impacts, this project supports research for a postdoctoral fellow.", "east": 75.0, "geometry": ["POINT(73.5 -67.5)"], "keywords": "Antarctica; Gamburtsev Mountains; Geochronology; Marine Sediments; NBP0101; ODP1166; Prydz Bay; Solid Earth; Southern Ocean", "locations": "Antarctica; Southern Ocean; Prydz Bay; Gamburtsev Mountains", "north": -66.0, "nsf_funding_programs": null, "persons": "Gehrels, George; Reiners, Peter", "project_titles": "Collaborative Research: SGER: Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains", "projects": [{"proj_uid": "p0000210", "repository": "USAP-DC", "title": "Collaborative Research: SGER: Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.0, "title": "Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains", "uid": "600090", "west": 72.0}, {"awards": null, "bounds_geometry": null, "date_created": "Thu, 06 Nov 2003 00:00:00 GMT", "description": "This presentation uses a series of paleogeographic and plate-tectonic reconstructions to show the broad patterns of Phanerozoic Earth history. Organization is by region and in geologic order from oldest to youngest for each region. The Time Slice link shows all maps and globes of all regions by geologic time (the Periods). \nOptions available from the menu are: \n- Paleogeographic globes, http://jan.ucc.nau.edu/~rcb7/paleogeographic.html; \n- Tectonics, Sedimentation, Paleogeography of North Atlantic Region, http://jan.ucc.nau.edu/~rcb7/nat.html; \n- Tectonics and Paleogeography of Mediterranean Region, http://jan.ucc.nau.edu/~rcb7/paleogeographic_alps.html; - Tectonics and Paleogeography of Central and Southern Asia, http://jan.ucc.nau.edu/~rcb7/paleogeographic_asia.html; and \n- Time Slice, http://jan.ucc.nau.edu/~rcb7/global_history.html, all maps and globes of all regions by geologic time, and a brief narrative for each time interval.", "east": null, "geometry": null, "keywords": null, "locations": null, "north": null, "nsf_funding_programs": null, "persons": "Blakey, Ronald C.", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": null, "title": "Regional Paleogeographic Views of Earth History", "uid": "600017", "west": null}]
X
X
Help on the Results MapX
This window can be dragged by its header, and can be resized from the bottom right corner.
Clicking the Layers button - the blue square in the top left of the Results Map - will display a list of map layers you can add or remove
from the currently displayed map view.
The Results Map and the Results Table
- The Results Map displays the centroids of the geographic bounds of all the results returned by the search.
- Results that are displayed in the current map view will be highlighted in blue and brought to the top of the Results Table.
- As the map is panned or zoomed, the highlighted rows in the table will update.
- If you click on a centroid on the map, it will turn yellow and display a popup with details for that project/dataset - including a link to the landing page. The bounds for the project(s)/dataset(s) selected will be displayed in red. The selected result(s) will be highlighted in red and brought to the top of the table.
- The default table sorting order is: Selected, Visible, Date (descending), but this can be changed by clicking on column headers in the table.
- Selecting Show on Map for an individual row will both display the geographic bounds for that result on a mini map, and also display the bounds and highlight the centroid on the Results Map.
- Clicking the 'Show boundaries' checkbox at the top of the Results Map will display all the bounds for the filtered results.
Defining a search area on the Results Map
- If you click on the Rectangle or Polygon icons in the top right of the Results Map, you can define a search area which will be added to any other search criteria already selected.
- After you have drawn a polygon, you can edit it using the Edit Geometry dropdown in the search form at the top.
- Clicking Clear in the map will clear any drawn polygon.
- Clicking Search in the map, or Search on the form will have the same effect.
- The returned results will be any projects/datasets with bounds that intersect the polygon.
- Use the Exclude project/datasets checkbox to exclude any projects/datasets that cover the whole Antarctic region.
Viewing map layers on the Results Map
To sort the table of search results, click the header of the column you wish to search by. To sort by multiple columns, hold down the shift key whilst selecting the sort columns in order.
Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Physical and geochemical data from shelf sediments eastern Antarctica
|
2147045 |
2024-12-16 | Learman, Deric |
Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments |
Shelf sediment samples were collected in Eastern Antarctica with the mega corer in 2023 (April). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set. | [] | [] | false | false |
NBP1402 diatom data
|
1143836 |
2024-10-21 | Leventer, Amy; NBP1402 science party, |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Totten Glacier is the termination of the largest marine-based portion of the East Antarctic Ice Sheet, the Aurora Subglacial Basin. Yet little is known about the glacial evolution of the catchment and the factors influencing its present and past behavior. Due its remote location and heavy sea ice, the continental shelf in front of the Totten Glacier had not been comprehensively surveyed prior to this study. Satellite observations indicate that the Totten ice drainage system is thinning, and it has been hypothesized that this thinning is in response to undermelting by warm ocean waters over the continental shelf. While this process is observed elsewhere in Antarctica (e.g. the rapidly retreating Pine Island Glacier in West Antarctica), the Totten Glacier system is potentially Antarcticas most important glacial drainage system due to its large size; it is three times larger than any system in West Antarctica. </br>The main goals of this proposal were: </br>To generate multibeam bathymetric maps of the continental shelf proximal to the Totten Glacier system to understand the recent regional glacial history and to document the pathways, if any, for circumpolar deep water to move onto the shelf. </br>To conduct a physical oceanographic survey of the region proximal to the Totten Glacier system, to determine the presence, if any, of warm ocean waters over the continental shelf.</br>To conduct a seismic survey of the continental shelf to assess the long-term evolution of the glacial system in the Aurora Subglacial Basin.</br>To collect marine sediment cores to determine the regional deglacial to Holocene climate history and the influence of warm circumpolar deep water. | ["POLYGON((117 -66,119.9 -66,122.8 -66,125.7 -66,128.6 -66,131.5 -66,134.4 -66,137.3 -66,140.2 -66,143.1 -66,146 -66,146 -66.1,146 -66.2,146 -66.3,146 -66.4,146 -66.5,146 -66.6,146 -66.7,146 -66.8,146 -66.9,146 -67,143.1 -67,140.2 -67,137.3 -67,134.4 -67,131.5 -67,128.6 -67,125.7 -67,122.8 -67,119.9 -67,117 -67,117 -66.9,117 -66.8,117 -66.7,117 -66.6,117 -66.5,117 -66.4,117 -66.3,117 -66.2,117 -66.1,117 -66))"] | ["POINT(131.5 -66.5)"] | false | false |
U-Pb zircon and apatite fission track dates for IRD (ice-rafted cobbles and mineral grains) from IODP379 drill sites
|
1939146 |
2024-08-27 | Siddoway, Christine |
Collaborative Research: Testing the Linchpin of WAIS Collapse with Diatoms and IRD in Pleistocene and Late Pliocene Strata of the Resolution Drift, Amundsen Sea, Antarctica |
The table contains sample identifiers, location data, and geochronology data (U-Pb zircon dates; apatite fission track determinations) from selected intervals of sediment cores obtained at sites U1532 (A, B, C, G) and U1533 (A, B) recovered during IODP Expedition 379 to the outer Amundsen Sea, Antarctica. | ["POLYGON((-109.1 -68.6,-108.94 -68.6,-108.78 -68.6,-108.61999999999999 -68.6,-108.46 -68.6,-108.3 -68.6,-108.14 -68.6,-107.98 -68.6,-107.82 -68.6,-107.66 -68.6,-107.5 -68.6,-107.5 -68.64,-107.5 -68.67999999999999,-107.5 -68.72,-107.5 -68.75999999999999,-107.5 -68.8,-107.5 -68.84,-107.5 -68.88,-107.5 -68.92,-107.5 -68.96,-107.5 -69,-107.66 -69,-107.82 -69,-107.98 -69,-108.14 -69,-108.3 -69,-108.46 -69,-108.61999999999999 -69,-108.78 -69,-108.94 -69,-109.1 -69,-109.1 -68.96,-109.1 -68.92,-109.1 -68.88,-109.1 -68.84,-109.1 -68.8,-109.1 -68.75999999999999,-109.1 -68.72,-109.1 -68.67999999999999,-109.1 -68.64,-109.1 -68.6))"] | ["POINT(-108.3 -68.8)"] | false | false |
Diatom assemblage from IODP Site U1357
|
1744871 |
2024-08-13 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes quantitative diatom assemblage data from 60 samples from IODP Site U1357B on the Adelie Basin. The record spans from 11,000 yBP to present. | ["POLYGON((100 -62,104.4 -62,108.8 -62,113.2 -62,117.6 -62,122 -62,126.4 -62,130.8 -62,135.2 -62,139.6 -62,144 -62,144 -64,144 -66,144 -68,144 -70,144 -72,144 -74,144 -76,144 -78,144 -80,144 -82,139.6 -82,135.2 -82,130.8 -82,126.4 -82,122 -82,117.6 -82,113.19999999999999 -82,108.8 -82,104.4 -82,100 -82,100 -80,100 -78,100 -76,100 -74,100 -72,100 -70,100 -68,100 -66,100 -64,100 -62))"] | ["POINT(122 -72)"] | false | false |
Diatom-bound and bulk sedimentary nitrogen isotopes from IODP Site U1357
|
1744871 |
2024-08-13 | Dove, Isabel; Kelly, Roger; Robinson, Rebecca |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; ‰ vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; ‰ vs air), and total nitrogen (wt%) from 121 samples from IODP Site U1357B in the Adelie Basin. The sediments are Holocene age (11 kyBP to present). | ["POLYGON((100 -62,104.4 -62,108.8 -62,113.2 -62,117.6 -62,122 -62,126.4 -62,130.8 -62,135.2 -62,139.6 -62,144 -62,144 -64,144 -66,144 -68,144 -70,144 -72,144 -74,144 -76,144 -78,144 -80,144 -82,139.6 -82,135.2 -82,130.8 -82,126.4 -82,122 -82,117.6 -82,113.19999999999999 -82,108.8 -82,104.4 -82,100 -82,100 -80,100 -78,100 -76,100 -74,100 -72,100 -70,100 -68,100 -66,100 -64,100 -62))"] | ["POINT(122 -72)"] | false | false |
Diatom-bound and bulk sedimentary N isotopes from ODP Site 1098, Western Antarctic Peninsula
|
1744871 |
2024-08-13 | Dove, Isabel; Jones, Colin; Kelly, Roger; Robinson, Rebecca |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; ‰ vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; ‰ vs air), and total nitrogen (wt%) from 81 Holocene and late deglacial-aged samples from ODP Site 1098B on the western Antarctic Peninsula. | ["POLYGON((-80 -59,-76.8 -59,-73.6 -59,-70.4 -59,-67.2 -59,-64 -59,-60.8 -59,-57.599999999999994 -59,-54.4 -59,-51.2 -59,-48 -59,-48 -60.6,-48 -62.2,-48 -63.8,-48 -65.4,-48 -67,-48 -68.6,-48 -70.2,-48 -71.8,-48 -73.4,-48 -75,-51.2 -75,-54.4 -75,-57.6 -75,-60.8 -75,-64 -75,-67.2 -75,-70.4 -75,-73.6 -75,-76.8 -75,-80 -75,-80 -73.4,-80 -71.8,-80 -70.2,-80 -68.6,-80 -67,-80 -65.4,-80 -63.8,-80 -62.2,-80 -60.6,-80 -59))"] | ["POINT(-64 -67)"] | false | false |
Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea
|
2000992 |
2024-07-10 | Romans, Brian W.; Varela, Natalia |
COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene |
This data set includes grain size information from late Pliocene through Pleistocene aged sediment recovered in cores from International Ocean Discovery Program (IODP) Expedition 374 Sites U1524 and U1525, on the continental slope and rise of the Ross Sea margin. There are two types of particle size data: (1) laser diffraction (Mastersizer 3000) data of silt-range sediment subsampled from mm-scale thick laminae/beds, and (2) x-ray-monitored settling (SediGraph 5120) data from muddy intervals directly overlying the silt laminae/beds. For Site U1524, there are 100 samples of Mastersizer data coupled with 100 samples of SediGraph data. For Site U1525, there are 50 samples of Mastersizer data coupled with 50 samples of SediGraph data. For both sites, the analyzed samples span the depth range of the core that contains the silty laminae/beds. | ["POLYGON((-174 -74.1667,-173.93 -74.1667,-173.86 -74.1667,-173.79 -74.1667,-173.72 -74.1667,-173.65 -74.1667,-173.58 -74.1667,-173.51000000000002 -74.1667,-173.44 -74.1667,-173.37 -74.1667,-173.3 -74.1667,-173.3 -74.25503,-173.3 -74.34336,-173.3 -74.43169,-173.3 -74.52002,-173.3 -74.60835,-173.3 -74.69668,-173.3 -74.78501,-173.3 -74.87334,-173.3 -74.96167,-173.3 -75.05,-173.37 -75.05,-173.44 -75.05,-173.51000000000002 -75.05,-173.58 -75.05,-173.65 -75.05,-173.72 -75.05,-173.79 -75.05,-173.86 -75.05,-173.93 -75.05,-174 -75.05,-174 -74.96167,-174 -74.87334,-174 -74.78501,-174 -74.69668,-174 -74.60835,-174 -74.52002,-174 -74.43169,-174 -74.34336,-174 -74.25503,-174 -74.1667))"] | ["POINT(-173.65 -74.60835)"] | false | false |
U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica
|
2042495 1644171 |
2024-07-01 | Edwards, Graham; Piccione, Gavin; Blackburn, Terrence; Tulaczyk, Slawek |
Collaborative Research: Reconstructing East Antarctica’s Past Response to Climate using Subglacial Precipitates U-Series Comminution Age Constraints on Taylor Valley Erosion |
This dataset contains uranium and thorium isotopic compositions (U-234, U-235, U-238, Th-230, Th-232) and major element compositions (Al, K, Na, Ca, Fe, Mn, reported as oxides) for silicate sediments from glaciogenic drifts associated with advances of Taylor Glacier in Taylor Valley, Antarctica. Isotopic measurements were obtained by ID-TIMS in the Keck Isotope Facility at UC Santa Cruz and elemental measurements were obtained by ICP-OES in the Plasma Analytical Laboratory. All measurements include fully propagated analytical and systematic (e.g. isotopic tracer) uncertainties. Chemical index of alteration was calculated from major element data. Prior to measurements, sediments were sieved to ≤125 μm grain sizes, separated into quartz-feldspar-rich and clay-rich aliquots by hydraulic settling, and subjected to sequential chemical extractions ("leaching") prior to silicate digestion. | ["POLYGON((161.9 -77.65,161.96 -77.65,162.02 -77.65,162.08 -77.65,162.14000000000001 -77.65,162.2 -77.65,162.26 -77.65,162.32 -77.65,162.38 -77.65,162.44 -77.65,162.5 -77.65,162.5 -77.66000000000001,162.5 -77.67,162.5 -77.68,162.5 -77.69,162.5 -77.7,162.5 -77.71000000000001,162.5 -77.72,162.5 -77.73,162.5 -77.74,162.5 -77.75,162.44 -77.75,162.38 -77.75,162.32 -77.75,162.26 -77.75,162.2 -77.75,162.14000000000001 -77.75,162.08 -77.75,162.02 -77.75,161.96 -77.75,161.9 -77.75,161.9 -77.74,161.9 -77.73,161.9 -77.72,161.9 -77.71000000000001,161.9 -77.7,161.9 -77.69,161.9 -77.68,161.9 -77.67,161.9 -77.66000000000001,161.9 -77.65))"] | ["POINT(162.2 -77.7)"] | false | false |
Sediment chemistry of ODP Site 1098
|
1744871 |
2024-04-24 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes measurements of opal (wt %), total organic carbon (wt %), total nitrogen (wt%), bulk nitrogen isotopic composition (d15Nbulk; ‰ vs air), and diatom-bound nitrogen isotopic composition (d15Ndb; ‰ vs air) from 36 samples from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments were deposited during a period of deglaciation about 12.5-12.3 ka. | ["POINT(-64.207 -64.86)"] | ["POINT(-64.207 -64.86)"] | false | false |
ODP Site 1098 deglacial diatom assemblage
|
1744871 |
2024-04-24 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes diatom assemblage and surface area data from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments are laminated and were deposited during a period of deglaciation about 12.5-12.3 ka. Quantitative diatom assemblage counts and surface area measurements are reported for 12 samples. | ["POINT(-64 -65)"] | ["POINT(-64 -65)"] | false | false |
Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica
|
2044924 |
2024-04-03 | Barrett, John | No project link provided | Microbial communities are the primary drivers of carbon cycling in the McMurdo Dry Valleys of Antarctica. Dense microbial mats, consisting mainly of photosynthetic cyanobacteria, occupy aquatic areas associated with streams and lakes. Other microbial communities also occur at lower densities as patchy surface biological soil crusts (biocrusts) across the terrestrial landscape. Multispectral satellite data have been used to model microbial mat abundance in high-density areas like stream and lake margins, but no previous studies had investigated the lower detection limits of biocrusts. Here, we describe remote sensing and field-based survey and sampling approaches to study the detectability and distribution of biocrusts in the McMurdo Dry Valleys. Using a combination of multi- and hyperspectral tools and spectral linear unmixing, we modeled the abundances of biocrust in eastern Taylor Valley. Our spectral approaches can detect low masses of biocrust material in laboratory microcosms down to biocrust concentrations of 1% by mass. These techniques also distinguish the spectra of biocrust from both surface rock and mineral signatures from orbit. We found that biocrusts are present throughout the soils of eastern Taylor Valley and are associated with diverse underlying soil communities. The densest biocrust communities identified in this study had total organic carbon 5x greater than the content of typical arid soils. The most productive biocrusts were located downslope of melting snowpacks in unique soil ecosystems that are distinct from the surrounding arid landscape. There are similarities between the snowpack and stream sediment communities (high diversity of soil invertebrates) as well as their ecosystem properties (e.g., persistence of liquid water, high transfer of available nutrients, lower salinity from flushing) compared to the typical arid terrestrial ecosystem of the dry valleys. Our approach extends the capability of orbital remote sensing of photosynthetic communities out of the aquatic margins and into the drier soils which comprise most of this landscape. This interdisciplinary work is critical for measuring and monitoring terrestrial carbon stocks and predicting future ecosystem dynamics in this currently water-limited but increasingly dynamic Antarctic landscape, which is particularly climate-sensitive and difficult to access. | ["POLYGON((161.70776367188 -77.519802097166,161.899475097661 -77.519802097166,162.091186523442 -77.519802097166,162.282897949223 -77.519802097166,162.474609375004 -77.519802097166,162.666320800785 -77.519802097166,162.858032226566 -77.519802097166,163.049743652347 -77.519802097166,163.241455078128 -77.519802097166,163.433166503909 -77.519802097166,163.62487792969 -77.519802097166,163.62487792969 -77.54867059480199,163.62487792969 -77.57753909243799,163.62487792969 -77.606407590074,163.62487792969 -77.63527608771,163.62487792969 -77.664144585346,163.62487792969 -77.69301308298199,163.62487792969 -77.72188158061799,163.62487792969 -77.750750078254,163.62487792969 -77.77961857589,163.62487792969 -77.808487073526,163.433166503909 -77.808487073526,163.241455078128 -77.808487073526,163.049743652347 -77.808487073526,162.858032226566 -77.808487073526,162.666320800785 -77.808487073526,162.474609375004 -77.808487073526,162.282897949223 -77.808487073526,162.091186523442 -77.808487073526,161.899475097661 -77.808487073526,161.70776367188 -77.808487073526,161.70776367188 -77.77961857589,161.70776367188 -77.750750078254,161.70776367188 -77.72188158061799,161.70776367188 -77.69301308298199,161.70776367188 -77.664144585346,161.70776367188 -77.63527608771,161.70776367188 -77.606407590074,161.70776367188 -77.57753909243799,161.70776367188 -77.54867059480199,161.70776367188 -77.519802097166))"] | ["POINT(162.666320800785 -77.664144585346)"] | false | false |
Ring shear bed deformation measurements
|
2013987 |
2023-12-13 | Zoet, Lucas |
Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory |
This dataset contains AMS results and microstructure analysis from different depths within the sheared till. | [] | [] | false | false |
Frozen fringe friction
|
2013987 |
2023-11-30 | Zoet, Lucas |
Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory |
This dataset comes from a ring shear device and is a series of values measured from the device including shear resistance as the fringe is growing | [] | [] | false | false |
Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments
|
1744871 |
2023-08-30 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset is the results of 3 experiments in which the spore-forming diatom Chaetoceros socialis was grown in culture and induced into resting spores by nitrate limitation. The nitrogen isotopic composition of accumulated biomass (δ15Nbiomass; ‰ vs air) and of diatom-bound organic N (δ15Ndb; ‰ vs air) are reported at two timepoints from each experiment: prior to and after resting spore formation. Experiments 1 and 2 provide measurements for CRS mixed with vegetative Chaetoceros cells, while Experiment 3 provides measurements for isolated CRS. Fluorescence and nitrate concentration was tracked throughout each experiment, with dissolved silica, ammonium, and total reduced nitrogen also measured in Experiment 3. | [] | [] | false | false |
Mercer Subglacial Lake radiocarbon and stable isotope data
|
1543347 |
2023-03-13 | Venturelli, Ryan; Rosenheim, Brad |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset includes radiocarbon (¹⁴C) and stable carbon isotope (δ¹³C) data for a sediment core from Mercer Subglacial Lake. In addition, this dataset includes ¹⁴C and δ¹³C for dissolved organic carbon, dissolved inorganic carbon, and particulate organic carbon from the Mercer Subglacial Lake water column. | ["POINT(-149.59134 -84.640287)"] | ["POINT(-149.59134 -84.640287)"] | false | false |
Sediment porewater properties data from Mercer Subglacial Lake
|
1543537 |
2023-02-03 | Dore, John; Michaud, Alexander; Skidmore, Mark; Tranter, Martyn; Steigmeyer, August; Science Team, SALSA |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset contains measurements of sediment porewater properties from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: specific conductance; water stable isotopes (δ2H and δ18O); dissolved gases (methane and its stable isotopes δ13C and δ2H, ethylene, and ethane); and major anions and cations. | ["POINT(-149.50134 -84.640287)"] | ["POINT(-149.50134 -84.640287)"] | false | false |
Discrete bulk sediment properties data from Mercer Subglacial Lake
|
1543537 |
2023-02-01 | Dore, John; Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset contains bulk sediment properties measurements from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: physical properties (bulk density, mass water content, porosity, shear strength, particle size distribution, and mineralogy); carbon (inorganic and organic); iron (ascorbate- and dithionite-extractable); and sulfur (acid-volatile and chromium-reducible). | ["POINT(-149.50134 -84.640287)"] | ["POINT(-149.50134 -84.640287)"] | false | false |
Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation
|
None | 2023-01-30 | Liu, Xiaodong | No project link provided | Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation | [] | [] | false | false |
Physical and geochemical data from shelf sediments near the Antartic Pennisula
|
2031442 |
2022-09-08 | Learman, Deric |
RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments |
Shelf sediment samples were collected around the Antarctic Peninsular with the mega corer in 2020 (Nov. to Dec.). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set (10). | [] | [] | false | false |
Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent
|
1743643 |
2022-06-22 | Passchier, Sandra; Hojnacki, Victoria; Li, Xiaona; States, Abbey; Lepp, Allison |
Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition |
This dataset contains measurements of major and trace elements on 190 samples of Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. The composition of detrital, biogenic and authigenic sediment components was assessed via whole rock geochemistry of sediment samples. Instrument analysis was completed at Montclair State University. | ["POINT(-42.933 -61.849)"] | ["POINT(-42.933 -61.849)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent
|
1743643 |
2022-06-21 | Passchier, Sandra; Lepp, Allison; Horowitz Castaldo, Josie; Light, Jennifer |
Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Diatoms were generally either absent or present in trace amounts in the Eocene-Oligocene interval and were not removed. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive Index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(-42.933 -61.849)"] | ["POINT(-42.933 -61.849)"] | false | false |
Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67°S to 55°S latitude in the Pacific Sector of the Southern Ocean
|
1341432 1341464 |
2022-06-02 | Jones, Janice L.; Closset, Ivia; Robinson, Rebecca; Brzezinski, Mark |
Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump |
This dataset contains data for particulate silicon, particulate carbon, particulate nitrogen, stable isotopes of nitrogen and stable isotopes of silicon in particulates from McLane pump profiles | ["POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))"] | ["POINT(-170 -60.5)"] | false | false |
Silicon concentration and isotopic composition measurements in seawater profiles, pore waters, interstitial waters and sediments from 67°S to 55°S latitude in the Pacific Sector of the Southern Ocean
|
1341432 |
2022-05-16 | Closset, Ivia; Jones, Janice L.; Brzezinski, Mark |
Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump |
This dataset contains data for stable isotopes of silicon in pore water, interstitial water, sediments and CTD profiles. | ["POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))"] | ["POINT(-170 -60.5)"] | false | false |
Joinville and Livingston Islands - rock and sediment OSL ages
|
1644197 1643868 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
detailed results for rock and sediment OSL ages; De calculation; dose rate calculation, fading, signal measurement | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches
|
1644197 1643868 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
sediment and rock samples were collected on Joinville and Livingston Islands for OSL dating; feldspar separates were prepared; data set includes Electron microprobe analysis of selected feldspar extracts; includes bmp and tif with elemental maps plus elemental concentrations and Ca:Na:K ratios for feldspar analysis | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
OSL data - Joinville and Livingston Islands - Raw data
|
1643868 1644197 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
raw OSL data for rock and sediment samples collected on Joinville and Livingston Islands | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy
|
1341464 |
2022-02-14 | Jones, Colin; Robinson, Rebecca; Brzezinski, Mark; Riesselman, Christina; Closset, Ivia; Kelly, Roger; Robinson, Rebecca |
Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump |
Tracking variations in the surface ocean supply and demand of nitrate, a key marine nutrient, can help constrain the contribution of biological production in driving past climate shifts. The nitrogen isotopic composition (as δ15N) of organic matter in marine sediments is a proxy for surface ocean nitrate supply and demand over time but it may be subject to alteration during sinking and burial. The isotopic composition of nitrogen contained in the shells, or frustules, of diatoms (δ15NDB) is protected and is therefore a potentially more robust tracer of nitrate use in the past. Here we show that δ15NDB in Southern Ocean community cultures does not depend on species composition. We found the εDB (= biomass δ15N - δ15NDB) of the community growouts was -4.8 ± 0.8‰, more than 10‰ different from previous monospecific growouts, but statistically indistinguishable from previous Southern Ocean and North Pacific surface ocean observations. The two community growouts, seeded with populations from 66° and 61°S, had distinct community compositions but indistinguishable εDB, suggesting species composition does not primarily set δ15NDB values in the Southern Ocean. Our results demonstrate that under nitrate-replete conditions, δ15NDB values of frustules sinking from the surface ocean robustly track surface ocean nitrate δ15N values and therefore nitrate supply and demand. | ["POLYGON((-170.4 -60.8,-170.36 -60.8,-170.32 -60.8,-170.28 -60.8,-170.24 -60.8,-170.2 -60.8,-170.16 -60.8,-170.12 -60.8,-170.08 -60.8,-170.04 -60.8,-170 -60.8,-170 -61.34,-170 -61.88,-170 -62.42,-170 -62.96,-170 -63.5,-170 -64.04,-170 -64.58,-170 -65.12,-170 -65.66,-170 -66.2,-170.04 -66.2,-170.08 -66.2,-170.12 -66.2,-170.16 -66.2,-170.2 -66.2,-170.24 -66.2,-170.28 -66.2,-170.32 -66.2,-170.36 -66.2,-170.4 -66.2,-170.4 -65.66,-170.4 -65.12,-170.4 -64.58,-170.4 -64.04,-170.4 -63.5,-170.4 -62.96,-170.4 -62.42,-170.4 -61.88,-170.4 -61.34,-170.4 -60.8))"] | ["POINT(-170.2 -63.5)"] | false | false |
Physical and geochemical data from five sediment cores collected offshore Thwaites Glacier
|
1738942 |
2022-01-27 | Lepp, Allison |
NSF-NERC: THwaites Offshore Research (THOR) |
This dataset contains measurements from grain-size, x-ray fluorescence (XRF), and physical properties (including magnetic susceptibility, water content, and shear strength) analyses of five sediment cores collected offshore Thwaites Glacier during cruises NBP19-02 (cores KC04, KC08, and KC23) and NBP20-02 (cores KC33 and KC67). We estimate the cores, which are between 213.5 and 297.5 cm in length, reflect deposition during the last ~10 kyr, consistent with published constraints of deglaciation of this region. Data are organized in Microsoft Excel spreadsheets and core locations are provided in a PDF. | ["POLYGON((-107.38 -74.64,-107.065 -74.64,-106.75 -74.64,-106.435 -74.64,-106.12 -74.64,-105.805 -74.64,-105.49 -74.64,-105.175 -74.64,-104.86 -74.64,-104.545 -74.64,-104.23 -74.64,-104.23 -74.683,-104.23 -74.726,-104.23 -74.769,-104.23 -74.812,-104.23 -74.855,-104.23 -74.898,-104.23 -74.941,-104.23 -74.984,-104.23 -75.027,-104.23 -75.07,-104.545 -75.07,-104.86 -75.07,-105.175 -75.07,-105.49 -75.07,-105.805 -75.07,-106.12 -75.07,-106.435 -75.07,-106.75 -75.07,-107.065 -75.07,-107.38 -75.07,-107.38 -75.027,-107.38 -74.984,-107.38 -74.941,-107.38 -74.898,-107.38 -74.855,-107.38 -74.812,-107.38 -74.769,-107.38 -74.726,-107.38 -74.683,-107.38 -74.64))"] | ["POINT(-105.805 -74.855)"] | false | false |
Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.
|
1826712 1443585 1443386 1443424 |
2022-01-13 | Kristan, Allyson; Maiti, Kanchan; McMahon, Kelton; Polito, Michael |
Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators |
This data set contains radiometric dating measurements from two aquatic sediment cores excavated from two separate sites (Salisbury Plain and Gold Harbor) on South Georgia Island in February 2019. It also contains biological and geochemical sediment proxy values from both sediment cores, including total carbon (%), total nitrogen (%), number of penguin feathers and eggshell fragments, number of seal hairs, and δ13C and δ15N stable isotope values. Cores were sectioned at 1cm intervals, and radiometric dating analyses were conducted on sediment fractions <850 µm by measuring for 210Pb and 226Ra (via 214Pb) by direct gamma counting using the high purity germanium planar detector in the Marine Geochemistry Laboratory at Louisiana State University (LSU). The 210Pbex profiles were used to calculate sedimentation rates using a steady state model that assumes constant rate of supply and constant sedimentation rate (Maiti et al., 2010). Geochemical analyses were performed on sediment fractions <125 µm using an Elemental Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS) in the Stable Isotope Ecology Lab at LSU. Biological counts of feathers and hairs were determined by enumeration using a dissecting microscope of sediment fractions >1000 µm. The data set also includes sediment core excavation site names and coordinates, date of excavation, sediment depth and age, and carbon to nitrogen isotopic ratios. Details of the data set and all relevant methods are provided in Kristan et al., 2021. | ["POLYGON((-37.33 -54.05,-37.192 -54.05,-37.054 -54.05,-36.916 -54.05,-36.778 -54.05,-36.64 -54.05,-36.502 -54.05,-36.364 -54.05,-36.226 -54.05,-36.088 -54.05,-35.95 -54.05,-35.95 -54.107,-35.95 -54.164,-35.95 -54.221,-35.95 -54.278,-35.95 -54.335,-35.95 -54.392,-35.95 -54.449,-35.95 -54.506,-35.95 -54.563,-35.95 -54.62,-36.088 -54.62,-36.226 -54.62,-36.364 -54.62,-36.502 -54.62,-36.64 -54.62,-36.778 -54.62,-36.916 -54.62,-37.054 -54.62,-37.192 -54.62,-37.33 -54.62,-37.33 -54.563,-37.33 -54.506,-37.33 -54.449,-37.33 -54.392,-37.33 -54.335,-37.33 -54.278,-37.33 -54.221,-37.33 -54.164,-37.33 -54.107,-37.33 -54.05))"] | ["POINT(-36.64 -54.335)"] | false | false |
LMG13-11 JKC-1 Paleoceanographic data
|
1433140 0732625 |
2021-11-15 | Shevenell, Amelia |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans |
This data set contains an age vs depth model and measurements of magnetic susceptibility, benthic foraminifera Bulimina aculeata d18O and d13C, bulk sediment GDGT data, and diatom assemblage data from USAP LMG13-11 JKC-1 sediment core (0-100 cm) archived at the Oregon State University ACC repository. All stable isotope and GDGT measurements were made at the University of South Florida College of Marine Science. Diatom assemblages were counted at Colgate University. The data set includes all replicate measurements. Details of the entire data set and all relevant methods are provided in Browne et al (submitted, 2021) | ["POLYGON((-69 -58,-67.7 -58,-66.4 -58,-65.1 -58,-63.8 -58,-62.5 -58,-61.2 -58,-59.9 -58,-58.6 -58,-57.3 -58,-56 -58,-56 -59,-56 -60,-56 -61,-56 -62,-56 -63,-56 -64,-56 -65,-56 -66,-56 -67,-56 -68,-57.3 -68,-58.6 -68,-59.9 -68,-61.2 -68,-62.5 -68,-63.8 -68,-65.1 -68,-66.4 -68,-67.7 -68,-69 -68,-69 -67,-69 -66,-69 -65,-69 -64,-69 -63,-69 -62,-69 -61,-69 -60,-69 -59,-69 -58))"] | ["POINT(-62.5 -63)"] | false | false |
NBP0702 surface sediment sample information and images
|
0440775 |
2021-09-17 | Leventer, Amy; Jacobs, Stanley |
The Amundsen Continental Shelf and the Antarctic Ice Sheet |
This dataset contains images and field description of Smith-McIntyre sediment grab samples from Expedition NBP0702 between the Ross Sea and the Amundsen Sea. | ["POLYGON((-180 -71.12,-172.34 -71.12,-164.68 -71.12,-157.02 -71.12,-149.36 -71.12,-141.7 -71.12,-134.04 -71.12,-126.38 -71.12,-118.72 -71.12,-111.06 -71.12,-103.4 -71.12,-103.4 -71.833,-103.4 -72.546,-103.4 -73.259,-103.4 -73.972,-103.4 -74.685,-103.4 -75.398,-103.4 -76.111,-103.4 -76.824,-103.4 -77.537,-103.4 -78.25,-111.06 -78.25,-118.72 -78.25,-126.38 -78.25,-134.04 -78.25,-141.7 -78.25,-149.36 -78.25,-157.02 -78.25,-164.68 -78.25,-172.34 -78.25,180 -78.25,178.657 -78.25,177.314 -78.25,175.971 -78.25,174.628 -78.25,173.285 -78.25,171.942 -78.25,170.599 -78.25,169.256 -78.25,167.913 -78.25,166.57 -78.25,166.57 -77.537,166.57 -76.824,166.57 -76.111,166.57 -75.398,166.57 -74.685,166.57 -73.972,166.57 -73.259,166.57 -72.546,166.57 -71.833,166.57 -71.12,167.913 -71.12,169.256 -71.12,170.599 -71.12,171.942 -71.12,173.285 -71.12,174.628 -71.12,175.971 -71.12,177.314 -71.12,178.657 -71.12,-180 -71.12))"] | ["POINT(-148.415 -74.685)"] | false | false |
Particle-size distributions of Eocene sediment from ODP Site 1166, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene sediment from Ocean Drilling Program Site 1166 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(74.787 -67.696167)"] | ["POINT(74.787 -67.696167)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 742, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 742 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(75.4045 -67.549667)"] | ["POINT(75.4045 -67.549667)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 739, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 739 in Prydz Bay. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(75.081833 -67.276167)"] | ["POINT(75.081833 -67.276167)"] | false | false |
Particle-size measurements for diamictites AND-2A sediment core, McMurdo Sound
|
0838842 |
2021-06-14 | Passchier, Sandra; Hansen, Melissa A. |
Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples |
This dataset contains measurements of particle-size distributions on four intervals of diamicitites from ANDRILL Site AND-2A. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2 and 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(167.0833 -77.8889)"] | ["POINT(167.0833 -77.8889)"] | false | false |
Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound
|
0342484 |
2021-06-14 | Passchier, Sandra; Candice, Falk |
Collaborative Research: ANDRILL - - Investigating Antarcticas Role in Cenozoic Global Environmental Change |
This dataset contains measurements of particle-size distributions on sediment from ANDRILL Site AND-2A. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2 and 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(167 -78)"] | ["POINT(167 -78)"] | false | false |
Particle-size distributions of Pliocene sediment from IODP Site U1359
|
1060080 |
2021-06-14 | Passchier, Sandra; Hansen, Melissa A.; Rosenberg, Jessica | No project link provided | This dataset contains measurements of terrigenous particle-size distributions on Pliocene sediment from Integrated Ocean Drilling Program Site U1359 on the Wilkes Land margin. Biogenic silica, carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate, and after supernatant was removed, digestion in 0.2 N NaOH at ~85 degrees for 1 hour. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(144 -65)"] | ["POINT(144 -65)"] | false | false |
NBP1402 JPC43 Diatom Data
|
1143836 |
2021-04-27 | Leventer, Amy |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
This dataset includes diatom data, both absolute abundance and relative contribution, for NBP1402 JPC43. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.1,121 -66.2,121 -66.3,121 -66.4,121 -66.5,121 -66.6,121 -66.7,121 -66.8,121 -66.9,121 -67,120.9 -67,120.8 -67,120.7 -67,120.6 -67,120.5 -67,120.4 -67,120.3 -67,120.2 -67,120.1 -67,120 -67,120 -66.9,120 -66.8,120 -66.7,120 -66.6,120 -66.5,120 -66.4,120 -66.3,120 -66.2,120 -66.1,120 -66))"] | ["POINT(120.5 -66.5)"] | false | false |
Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment
|
1724670 |
2020-10-05 | Williams, Trevor |
Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance |
This dataset contains 40Ar/39Ar measurements on detrital mineral grains from subglacial till and proximal glacimarine sediment from nine sediment cores along the front of the Filchner and Ronne Ice Shelves. | ["POLYGON((-65 -74,-61 -74,-57 -74,-53 -74,-49 -74,-45 -74,-41 -74,-37 -74,-33 -74,-29 -74,-25 -74,-25 -74.6,-25 -75.2,-25 -75.8,-25 -76.4,-25 -77,-25 -77.6,-25 -78.2,-25 -78.8,-25 -79.4,-25 -80,-29 -80,-33 -80,-37 -80,-41 -80,-45 -80,-49 -80,-53 -80,-57 -80,-61 -80,-65 -80,-65 -79.4,-65 -78.8,-65 -78.2,-65 -77.6,-65 -77,-65 -76.4,-65 -75.8,-65 -75.2,-65 -74.6,-65 -74))"] | ["POINT(-45 -77)"] | false | false |
Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment
|
1724670 |
2020-10-05 | Williams, Trevor |
Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance |
This dataset contains 40Ar/39Ar measurements on detrital mineral grains from till in modern moraines at the edges of the Institute, Foundation, Academy, Recovery, and the Slessor glaciers / ice streams. | ["POLYGON((-70 -80,-65 -80,-60 -80,-55 -80,-50 -80,-45 -80,-40 -80,-35 -80,-30 -80,-25 -80,-20 -80,-20 -80.6,-20 -81.2,-20 -81.8,-20 -82.4,-20 -83,-20 -83.6,-20 -84.2,-20 -84.8,-20 -85.4,-20 -86,-25 -86,-30 -86,-35 -86,-40 -86,-45 -86,-50 -86,-55 -86,-60 -86,-65 -86,-70 -86,-70 -85.4,-70 -84.8,-70 -84.2,-70 -83.6,-70 -83,-70 -82.4,-70 -81.8,-70 -81.2,-70 -80.6,-70 -80))"] | ["POINT(-45 -83)"] | false | false |
Argon thermochronological data on detrital mineral grains from the Weddell Sea embayment
|
1724670 |
2020-10-05 | Williams, Trevor |
Collaborative Research: Deglacial Ice Dynamics in the Weddell Sea Embayment using Sediment Provenance |
This dataset contains 40Ar/39Ar measurements on detrital mineral grains from ice-rafted detritus from sediment core PS1575-1 in the NW Weddell Sea. The depositional age of the sediments is approx. 0 to 300 ka. | ["POLYGON((-50 -62,-49 -62,-48 -62,-47 -62,-46 -62,-45 -62,-44 -62,-43 -62,-42 -62,-41 -62,-40 -62,-40 -62.3,-40 -62.6,-40 -62.9,-40 -63.2,-40 -63.5,-40 -63.8,-40 -64.1,-40 -64.4,-40 -64.7,-40 -65,-41 -65,-42 -65,-43 -65,-44 -65,-45 -65,-46 -65,-47 -65,-48 -65,-49 -65,-50 -65,-50 -64.7,-50 -64.4,-50 -64.1,-50 -63.8,-50 -63.5,-50 -63.2,-50 -62.9,-50 -62.6,-50 -62.3,-50 -62))"] | ["POINT(-45 -63.5)"] | false | false |
ANTAEM project airborne EM resistivity data from McMurdo Region
|
1644187 |
2020-09-12 | Tulaczyk, Slawek |
Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica |
The ANTAEM survey was carried out in the period November 12th to 28th, 2018, with the SkyTEM 312 system. Twenty-one missions (flights) were conducted over 11 production days of helicopter service, resulting in a total of approximately ~3400 line km of data. The SkyTEM system records data from take-off until landing resulting in multiple lines converging to the landing pads in McMurdo and at Marble Point. The production without overlapping lines adds up to approximately 2900 line km. The flight speed was approximately 120 km/h at a target flight altitude of ~50 m (sensor height), but the actual sensor height varies depending on the terrain. The surveys were carried out with a Bell 212 helicopter, which carried the SkyTEM sensor as a sling load. The SkyTEM system was configured in a standard two-moment setup (low moment, LM and high moment, HM). Areas with extremely resistive dry and/or frozen sediment/bedrock, and glacier ice often produce EM-signals with amplitudes below the detection level of the system. Data from these low signal environments cannot be inverted into resistivity models. Data with strong induced polarization effects cannot be inverted for resistivity either. These data were discharged in this standard data delivery. The EM-data and inversion result (resistivity models) are delivered in the SkyTEM2018_dat.xyz and SkyTEM2018_inv.xyz files respectably. The RECORD number in the two files links data and model together. EM-data and data uncertainty for data entering inversion. Info stated in file Header: NAN value, Data unit, Coordinate system, Gate times. The SkyTEM system uses at High-Low moment data recording cycle, therefore only a subset of the total 40 time gates are preset for each moment. The standard lateral constraints inversion (LCI), delivered in the SkyTEM2018_inv.xyz file, was carried out with a smooth 30 layered resistivity model discretized to a depth of 500 m. A depth of investigation (DOI) was estimated for each resistivity model. | ["POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9))"] | ["POINT(164.75 -77.6)"] | false | false |
NBP0505 sediment core locations
|
0338137 |
2020-07-17 | Wellner, Julia; Anderson, John |
Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica |
Excel file with station names, location and water depth and description of the coring device for NBP0505. | ["POLYGON((-76 -45.5,-75.2 -45.5,-74.4 -45.5,-73.6 -45.5,-72.8 -45.5,-72 -45.5,-71.2 -45.5,-70.4 -45.5,-69.6 -45.5,-68.8 -45.5,-68 -45.5,-68 -46.43,-68 -47.36,-68 -48.29,-68 -49.22,-68 -50.15,-68 -51.08,-68 -52.01,-68 -52.94,-68 -53.87,-68 -54.8,-68.8 -54.8,-69.6 -54.8,-70.4 -54.8,-71.2 -54.8,-72 -54.8,-72.8 -54.8,-73.6 -54.8,-74.4 -54.8,-75.2 -54.8,-76 -54.8,-76 -53.87,-76 -52.94,-76 -52.01,-76 -51.08,-76 -50.15,-76 -49.22,-76 -48.29,-76 -47.36,-76 -46.43,-76 -45.5))"] | ["POINT(-72 -50.15)"] | false | false |
NBP0505 CTD data
|
0338137 |
2020-07-17 | Wellner, Julia; Anderson, John |
Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica |
Raw CTD data from expedition NBP0505 collected with the Aanderaa and Seacat CTD systems | ["POLYGON((-76 -45.5,-75.2 -45.5,-74.4 -45.5,-73.6 -45.5,-72.8 -45.5,-72 -45.5,-71.2 -45.5,-70.4 -45.5,-69.6 -45.5,-68.8 -45.5,-68 -45.5,-68 -46.43,-68 -47.36,-68 -48.29,-68 -49.22,-68 -50.15,-68 -51.08,-68 -52.01,-68 -52.94,-68 -53.87,-68 -54.8,-68.8 -54.8,-69.6 -54.8,-70.4 -54.8,-71.2 -54.8,-72 -54.8,-72.8 -54.8,-73.6 -54.8,-74.4 -54.8,-75.2 -54.8,-76 -54.8,-76 -53.87,-76 -52.94,-76 -52.01,-76 -51.08,-76 -50.15,-76 -49.22,-76 -48.29,-76 -47.36,-76 -46.43,-76 -45.5))"] | ["POINT(-72 -50.15)"] | false | false |
Isotopic data from Whillans Ice Stream grounding zone, West Antarctica
|
None | 2020-07-15 | Venturelli, Ryan A |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset contains total organic carbon (%TOC) and carbon isotopic data (δ¹³C, Δ¹⁴C) from sediments retrieved from the Whillans Ice Stream grounding zone during the 2015 Antarctic field season. All %TOC and sediment preparations were done at the University of South Florida. Radiocarbon measurements were done at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) laboratory. | ["POINT(-163.61187 -84.33543)"] | ["POINT(-163.61187 -84.33543)"] | false | false |
Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf
|
1341669 0732711 |
2020-06-19 | DeMaster, David; Taylor, Richard |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
This file contains Pb-210 data from bulk sediments beneath the collapsed Larsen A Ice Shelf and C-14 data from the organic fraction of the same samples. | ["POLYGON((-61 -64,-60.5 -64,-60 -64,-59.5 -64,-59 -64,-58.5 -64,-58 -64,-57.5 -64,-57 -64,-56.5 -64,-56 -64,-56 -64.1,-56 -64.2,-56 -64.3,-56 -64.4,-56 -64.5,-56 -64.6,-56 -64.7,-56 -64.8,-56 -64.9,-56 -65,-56.5 -65,-57 -65,-57.5 -65,-58 -65,-58.5 -65,-59 -65,-59.5 -65,-60 -65,-60.5 -65,-61 -65,-61 -64.9,-61 -64.8,-61 -64.7,-61 -64.6,-61 -64.5,-61 -64.4,-61 -64.3,-61 -64.2,-61 -64.1,-61 -64))"] | ["POINT(-58.5 -64.5)"] | false | false |
Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf
|
0636773 1341669 |
2020-05-11 | DeMaster, David; Taylor, Richard; Smith, Craig; Isla, Enrique; Thomas, Carrie |
Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
This data set is used to describe a new technique for assessing labile organic carbon (LOC) abundances and mean residence times in marine sediments. Radiocarbon is used to determine abundances of labile organic carbon and then a diagenetic organic carbon model, coupled with sediment biotrubation coefficients, is used to assess LOC mean residence times. | ["POLYGON((-71 -64,-70.4 -64,-69.8 -64,-69.2 -64,-68.6 -64,-68 -64,-67.4 -64,-66.8 -64,-66.2 -64,-65.6 -64,-65 -64,-65 -64.7,-65 -65.4,-65 -66.1,-65 -66.8,-65 -67.5,-65 -68.2,-65 -68.9,-65 -69.6,-65 -70.3,-65 -71,-65.6 -71,-66.2 -71,-66.8 -71,-67.4 -71,-68 -71,-68.6 -71,-69.2 -71,-69.8 -71,-70.4 -71,-71 -71,-71 -70.3,-71 -69.6,-71 -68.9,-71 -68.2,-71 -67.5,-71 -66.8,-71 -66.1,-71 -65.4,-71 -64.7,-71 -64))"] | ["POINT(-68 -67.5)"] | false | false |
Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101
|
9909367 |
2020-05-01 | Leventer, Amy |
Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin |
This data set was acquired with a Jumbo Piston Core Sediment Sampler during R/V Nathaniel B. Palmer expedition NBP0101 conducted in 2001. This data file is of Microsoft Excel format and includes Quantitative Diatom Assemblage data; counts completed on randomly settled slides (Scherer, R.P., 1994. A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles. Journal of Paleolimnology, 12 (1), 171-178, doi:10.1007/BF00678093). These counts were completed at closely spaced intervals in NBP0101 JPC41, a jumbo piston core from Iceberg Alley, Mac.Robertson Shelf, East Antarctica | ["POINT(62.99 -67.13)"] | ["POINT(62.99 -67.13)"] | false | false |
Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203
|
0732711 1341669 |
2020-05-01 | Smith, Craig |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems. Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203. Data were acquired as part of the project(s): Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems (LARISSA); and Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change. | ["POLYGON((-61 -62,-60.4 -62,-59.8 -62,-59.2 -62,-58.6 -62,-58 -62,-57.4 -62,-56.8 -62,-56.2 -62,-55.6 -62,-55 -62,-55 -62.34,-55 -62.68,-55 -63.02,-55 -63.36,-55 -63.7,-55 -64.04,-55 -64.38,-55 -64.72,-55 -65.06,-55 -65.4,-55.6 -65.4,-56.2 -65.4,-56.8 -65.4,-57.4 -65.4,-58 -65.4,-58.6 -65.4,-59.2 -65.4,-59.8 -65.4,-60.4 -65.4,-61 -65.4,-61 -65.06,-61 -64.72,-61 -64.38,-61 -64.04,-61 -63.7,-61 -63.36,-61 -63.02,-61 -62.68,-61 -62.34,-61 -62))"] | ["POINT(-58 -63.7)"] | false | false |
Species List, Species Abundance, and Sediment Geochemistry processed data acquired during Laurence M. Gould expedition LMG0802
|
0636806 0636773 |
2020-04-30 | Smith, Craig; DeMaster, David |
Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling |
This data set was acquired with a Box Core Sediment Sampler, Digital Camera, and Sediment Core Sampler during Laurence M. Gould expedition LMG0802 conducted in 2008. The data files are in Microsoft Excel format and include Species List, Species Abundance, and Sediment Geochemistry data that was processed after collection. | ["POLYGON((-72 -59,-71 -59,-70 -59,-69 -59,-68 -59,-67 -59,-66 -59,-65 -59,-64 -59,-63 -59,-62 -59,-62 -59.95,-62 -60.9,-62 -61.85,-62 -62.8,-62 -63.75,-62 -64.7,-62 -65.65,-62 -66.6,-62 -67.55,-62 -68.5,-63 -68.5,-64 -68.5,-65 -68.5,-66 -68.5,-67 -68.5,-68 -68.5,-69 -68.5,-70 -68.5,-71 -68.5,-72 -68.5,-72 -67.55,-72 -66.6,-72 -65.65,-72 -64.7,-72 -63.75,-72 -62.8,-72 -61.85,-72 -60.9,-72 -59.95,-72 -59))"] | ["POINT(-67 -63.75)"] | false | false |
Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf
|
1443680 |
2019-12-31 | Smith, Craig |
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco) |
Sediment macrofaunal data collected by megacore (10-cm diameter sample tubes) along a down-fjord transect from inner Andvord Bay out onto the open continental shelf on the West Antarctic Peninsula. Sediment core samples from 0 - 10 cm depths were fixed in 4% formaldehyde, sieved on a 300 micron seive, and sorted with a dissecting microscope. | ["POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64))"] | ["POINT(-64 -64.5)"] | false | false |
Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set
|
0839059 |
2019-12-19 | Coenen, Jason; Castañeda, Isla; Warny, Sophie; Baudoin, Patrick; Scherer, Reed Paul; Askin, Rosemary |
Collaborative Research: Integrative Study of Marine Ice Sheet Stability & Subglacial Life Habitats in W Antarctica - Lake & Ice Stream Subglacial Access Research Drilling (LISSARD) |
This data set includes biomarker data presented in Paleogene marine and terrestrial development of the West Antarctic Rift System. Included in the alkane sheet are the Terrestrial/aquatic (T/A) n-alkane ratio, total long (C27-C33)- and mid-chain (C23 and C25) n-alkane concentrations in units of ng alkanes per g sediment extracted, and the n-alkane average chain-length (ACL). Included in the glycerol dialkyl glycerol tetraethers (GDGT) sheet are the TEX86 sea surface temperature estimates with multiple calibrations discussed in the text, the MBT’5ME mean annual air temperature estimates, the branched and isoprenoid tetraether (BIT) index. | ["POLYGON((-180 -80,-174 -80,-168 -80,-162 -80,-156 -80,-150 -80,-144 -80,-138 -80,-132 -80,-126 -80,-120 -80,-120 -80.5,-120 -81,-120 -81.5,-120 -82,-120 -82.5,-120 -83,-120 -83.5,-120 -84,-120 -84.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -85,180 -84.5,180 -84,180 -83.5,180 -83,180 -82.5,180 -82,180 -81.5,180 -81,180 -80.5,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,180 -80,-180 -80))"] | ["POINT(-150 -82.5)"] | false | false |
Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography
|
1443420 |
2019-10-27 | Dodd, Justin; Abbott, Tirzah |
Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography |
The Andrill-1B (AND-1B) sediment core from under the Ross Ice Shelf in McMurdo Sound, Antarctica, recovered a mid to late Pliocene (~4.68 to 3.44 Ma) age diatomite unit with d18Odiatom values that range from +32.6 to +37.6 ‰ (n=50 | ["POINT(167.083333 -77.888889)"] | ["POINT(167.083333 -77.888889)"] | false | false |
Easten Antarctic Peninsula Surface Sediment Diatom Data
|
0732625 9714371 |
2019-09-16 | Leventer, Amy |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans |
Diatom data from eastern side of Antarctic Peninsula: This file includes quantitative diatom data for surface samples collected on numerous cruises to the eastern side of the Antarctic Peninsula, including NBP0003, NBP0107, LMG0502, NBP0603, and NBP1203. Samples were collected using a variety of tools including Smith-McIntyre Grab, Kasten Core and Jumbo Kasten Core. These data were generated by Amy Leventer (aleventer@colgate.edu) and undergraduate students at Colgate University. All questions regarding the specifics of these data should be directed to Amy Leventer. Quantitative diatom slides were prepared according to the settling technique of Scherer (1995). Cover slips were adhered to the slides using Norland Optical Adhesive #61. Slides were observed under Olympus CX31, BX50 and BX60, and Zeiss Primo Star light microscopes, using a 100X oil immersion objective for a total magnification of 1000X. A minimum of 400 valves or 10 transects was counted for each slide, depending on the absolute diatom abundance. Valves were only counted if >50% complete. Diatoms were identified to species level when possible (Crosta et al., 2005; Armand et al., 2005; Cefarelli et al., 2010). Armand, L.K., X. Crosta, O. Romero, J. J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species, Paleogeography, Paleoclimatology, Paleoecology, 223, 93-126. Cefarelli, A.O., M. E. Ferrario, G. O. Almandoz, A. G. Atencio, R. Akselman, M. Vernet (2010), Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance, Polar Biology, 33(2), 1463-1484. Crosta, X., O. Romero, L. K. Armand, J. Pichon (2005), The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species, Palaeogeography, Palaeoclimatology, Palaeoecology, 223, 66-92. Scherer, R. P., A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles, J. Paleolimnol., 12, 171–178, 1995. | ["POLYGON((-64 -63,-63.1 -63,-62.2 -63,-61.3 -63,-60.4 -63,-59.5 -63,-58.6 -63,-57.7 -63,-56.8 -63,-55.9 -63,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-55 -65.4,-55 -65.8,-55 -66.2,-55 -66.6,-55 -67,-55.9 -67,-56.8 -67,-57.7 -67,-58.6 -67,-59.5 -67,-60.4 -67,-61.3 -67,-62.2 -67,-63.1 -67,-64 -67,-64 -66.6,-64 -66.2,-64 -65.8,-64 -65.4,-64 -65,-64 -64.6,-64 -64.2,-64 -63.8,-64 -63.4,-64 -63))"] | ["POINT(-59.5 -65)"] | false | false |
Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)
|
1443680 |
2019-07-16 | Eidam, Emily; Nittrouer, Charles; Homolka, Khadijah; Smith, Craig |
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco) |
This dataset includes Pb-210 activities, grain-size distributions, and x-radiograph negatives for cores collected primarily during NBP1603 (and also LMG1510) as part of the FjordEco project in Andvord Bay and surrounding areas (Gerlache Strait, and Station B on the shelf). Data are from subsampled intervals of kasten cores and box cores, as well as one megacore. Samples were x-rayed, sliced, and bagged onboard the vessel. Grain-size and Pb-210 analyses were completed in the Sediment Dynamics Lab within the University of Washington School of Oceanography (PI C. Nittrouer). | ["POLYGON((-65.561 -64.6538,-65.2471 -64.6538,-64.9332 -64.6538,-64.6193 -64.6538,-64.3054 -64.6538,-63.9915 -64.6538,-63.6776 -64.6538,-63.3637 -64.6538,-63.0498 -64.6538,-62.7359 -64.6538,-62.422 -64.6538,-62.422 -64.67842,-62.422 -64.70304,-62.422 -64.72766,-62.422 -64.75228,-62.422 -64.7769,-62.422 -64.80152,-62.422 -64.82614,-62.422 -64.85076,-62.422 -64.87538,-62.422 -64.9,-62.7359 -64.9,-63.0498 -64.9,-63.3637 -64.9,-63.6776 -64.9,-63.9915 -64.9,-64.3054 -64.9,-64.6193 -64.9,-64.9332 -64.9,-65.2471 -64.9,-65.561 -64.9,-65.561 -64.87538,-65.561 -64.85076,-65.561 -64.82614,-65.561 -64.80152,-65.561 -64.7769,-65.561 -64.75228,-65.561 -64.72766,-65.561 -64.70304,-65.561 -64.67842,-65.561 -64.6538))"] | ["POINT(-63.9915 -64.7769)"] | false | false |
NBP1502 YoYo camera benthic images from Ross Sea
|
1246357 |
2019-06-03 | Bart, Philip |
Timing and Duration of the LGM and Post-LGM Grounding Events in Whales Deep Paleo Ice Stream, Eastern Ross Sea Middle Continental Shelf |
Still and video benthic images collected during expedition NBP1502 in the Ross Sea using a YoYo camera system. | ["POLYGON((-171 -75.8,-170.5 -75.8,-170 -75.8,-169.5 -75.8,-169 -75.8,-168.5 -75.8,-168 -75.8,-167.5 -75.8,-167 -75.8,-166.5 -75.8,-166 -75.8,-166 -75.99,-166 -76.18,-166 -76.37,-166 -76.56,-166 -76.75,-166 -76.94,-166 -77.13,-166 -77.32,-166 -77.51,-166 -77.7,-166.5 -77.7,-167 -77.7,-167.5 -77.7,-168 -77.7,-168.5 -77.7,-169 -77.7,-169.5 -77.7,-170 -77.7,-170.5 -77.7,-171 -77.7,-171 -77.51,-171 -77.32,-171 -77.13,-171 -76.94,-171 -76.75,-171 -76.56,-171 -76.37,-171 -76.18,-171 -75.99,-171 -75.8))"] | ["POINT(-168.5 -76.75)"] | false | false |
Geochemical and sedimentologic data from NBP01-01 JPC-34
|
1246378 |
2019-05-10 | Shevenell, Amelia |
Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica |
This dataset contains 14C data, magnetic susceptibility, relative grain size percentages, 10Be | ["POLYGON((70 -68,70.5 -68,71 -68,71.5 -68,72 -68,72.5 -68,73 -68,73.5 -68,74 -68,74.5 -68,75 -68,75 -68.2,75 -68.4,75 -68.6,75 -68.8,75 -69,75 -69.2,75 -69.4,75 -69.6,75 -69.8,75 -70,74.5 -70,74 -70,73.5 -70,73 -70,72.5 -70,72 -70,71.5 -70,71 -70,70.5 -70,70 -70,70 -69.8,70 -69.6,70 -69.4,70 -69.2,70 -69,70 -68.8,70 -68.6,70 -68.4,70 -68.2,70 -68))"] | ["POINT(72.5 -69)"] | false | false |
Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica
|
9909367 |
2019-04-25 | Leventer, Amy |
Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin |
This data set describes diatom assemblages and abundances from two sediment cores retrieved from Edward VIII Gulf. The assemblages are used to reconstruct paleoceanographic conditions throughout the Holocene. | ["POLYGON((57 -66,57.3 -66,57.6 -66,57.9 -66,58.2 -66,58.5 -66,58.8 -66,59.1 -66,59.4 -66,59.7 -66,60 -66,60 -66.1,60 -66.2,60 -66.3,60 -66.4,60 -66.5,60 -66.6,60 -66.7,60 -66.8,60 -66.9,60 -67,59.7 -67,59.4 -67,59.1 -67,58.8 -67,58.5 -67,58.2 -67,57.9 -67,57.6 -67,57.3 -67,57 -67,57 -66.9,57 -66.8,57 -66.7,57 -66.6,57 -66.5,57 -66.4,57 -66.3,57 -66.2,57 -66.1,57 -66))"] | ["POINT(58.5 -66.5)"] | false | false |
Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments
|
1758224 |
2019-03-15 | Salvatore, Mark |
EAGER: Surface Variability and Spectral Analyses of the Central Transantarctic Mountains, Antarctica |
This data set contains reflectance spectra (350 - 2500 nm) of a range of rocks and sediments from the Central Transantarctic Mountains. Data were acquired using an Analytical Spectral Devices (ASD) FieldSpec4 high-resolution spectrometer under illumination with a high-output halogen bulb, with illumination and observation angles fixed at 0 and 30 degrees off-nadir, respectively. Data were acquired for the purposes of validation and 'ground truthing' of orbital multispectral data. | ["POLYGON((-180 -83,-177 -83,-174 -83,-171 -83,-168 -83,-165 -83,-162 -83,-159 -83,-156 -83,-153 -83,-150 -83,-150 -83.5,-150 -84,-150 -84.5,-150 -85,-150 -85.5,-150 -86,-150 -86.5,-150 -87,-150 -87.5,-150 -88,-153 -88,-156 -88,-159 -88,-162 -88,-165 -88,-168 -88,-171 -88,-174 -88,-177 -88,180 -88,177 -88,174 -88,171 -88,168 -88,165 -88,162 -88,159 -88,156 -88,153 -88,150 -88,150 -87.5,150 -87,150 -86.5,150 -86,150 -85.5,150 -85,150 -84.5,150 -84,150 -83.5,150 -83,153 -83,156 -83,159 -83,162 -83,165 -83,168 -83,171 -83,174 -83,177 -83,-180 -83))"] | ["POINT(180 -85.5)"] | false | false |
Fjord-Eco_Sediment_OrgC_OrgN_Data - Craig Smith
|
1443680 |
2019-02-13 | Smith, Craig |
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco) |
Sediment organic carbon and organic nitrogen content (percent mass) in 6 depth intervals (0-1cm, 1-2cm, 3-4cm, 5-6cm, 7-8cm , 9-10cm) in sediment cores collected by OSIL Megacore (10 cm diameter tubes) along the five-station FjordEco Transect from inner Andvord Bay to the open continental shelf at FOODBANCS Station B. | ["POLYGON((-65 -64,-64.7 -64,-64.4 -64,-64.1 -64,-63.8 -64,-63.5 -64,-63.2 -64,-62.9 -64,-62.6 -64,-62.3 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.3 -65,-62.6 -65,-62.9 -65,-63.2 -65,-63.5 -65,-63.8 -65,-64.1 -65,-64.4 -65,-64.7 -65,-65 -65,-65 -64.9,-65 -64.8,-65 -64.7,-65 -64.6,-65 -64.5,-65 -64.4,-65 -64.3,-65 -64.2,-65 -64.1,-65 -64))"] | ["POINT(-63.5 -64.5)"] | false | false |
Palynological samples
|
1048343 |
2019-02-01 | Warny, Sophie |
CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program |
Thanks to grant # U.S. National Science Foundation ANT-1048343, our group was selected to study about 700 of the recently-acquired sediment samples in Antarctica, covering ~9 regions and geological time frames ranging from the Paleocene to today. The samples were processed for palynological analyses and the slides are curated at the LSU CENEX center. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Ross Sea unconformities digital grids in depth and two-way time
|
1341585 |
2018-05-25 | Sorlien, Christopher; Wilson, Douglas S. |
Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea |
This data set includes digital 1 km grids of sub-bottom stratigraphy of most of Ross Sea. In addition to acoustic basement (same as top syn-rift sedimentary rocks in Central Trough and probably other basins), these grids include Oligocene and Miocene horizons that are unconformities in most areas. A sea floor grid is also included. Except for the sea floor grid, the grids are trimmed to be relatively close to control of interpreted seismic stratigraphy. The grids are provided in two way travel time and in depth. Math can be performed on the corresponding time and depth grids to recreate the 3D interval velocity model that was used. The velocity of the water used was 1450 m/s. More detailed descriptions of the work are found in the Final NSF report for PLR1341585 by C. Sorlien, B. Luyendyk, and D. Wilson. The grids are continuous so are merged with the sea floor where there is outcrop, or with basement if there is onlap, or with a young unconformity where there is sub-bottom truncation. The filenames include the name of the horizon (unconformity) and whether they are in time or depth. \"etc.\" means there are two or more horizons that have been merged. Most of the horizons are named and defined in the ANTOSTRAT (1995) atlas. The starting points for many of these horizons are ANTOSTRAT [1995] near DSDP sites 273, 272, and 270. In other areas we deviate from the interpretation of ANTOSTRAT [1995]. late Oligocene through middle Miocene horizons, interpreted very close to the ANTOSTRAT [1995] at DSDP Site 273 in Central Trough, are much deeper in our interpretation within Terror Rift. These horizon grids usually include the sea floor where there is outcrop or acoustic basement (top syn-rift in some basins) where there is onlap. ANTOSTRAT (1995), Seismic Stratigraphic Atlas of the Ross Sea, in Geology and Seismic Stratigraphy of the Antarctic Margin, edited by A. K. Cooper, Barker, P. F., Brancolini, G., 22 plates, American Geophysical Union, Washington, D.C. | ["POLYGON((-180 -73.22,-179.17 -73.22,-178.34 -73.22,-177.51 -73.22,-176.68 -73.22,-175.85 -73.22,-175.02 -73.22,-174.19 -73.22,-173.36 -73.22,-172.53 -73.22,-171.7 -73.22,-171.7 -73.765,-171.7 -74.31,-171.7 -74.855,-171.7 -75.4,-171.7 -75.945,-171.7 -76.49,-171.7 -77.035,-171.7 -77.58,-171.7 -78.125,-171.7 -78.67,-172.53 -78.67,-173.36 -78.67,-174.19 -78.67,-175.02 -78.67,-175.85 -78.67,-176.68 -78.67,-177.51 -78.67,-178.34 -78.67,-179.17 -78.67,180 -78.67,178.56 -78.67,177.12 -78.67,175.68 -78.67,174.24 -78.67,172.8 -78.67,171.36 -78.67,169.92 -78.67,168.48 -78.67,167.04 -78.67,165.6 -78.67,165.6 -78.125,165.6 -77.58,165.6 -77.035,165.6 -76.49,165.6 -75.945,165.6 -75.4,165.6 -74.855,165.6 -74.31,165.6 -73.765,165.6 -73.22,167.04 -73.22,168.48 -73.22,169.92 -73.22,171.36 -73.22,172.8 -73.22,174.24 -73.22,175.68 -73.22,177.12 -73.22,178.56 -73.22,-180 -73.22))"] | ["POINT(176.95 -75.945)"] | false | false |
2016 Paleomagnetic samples from the James Ross Basin, Antarctica
|
1341729 |
2018-04-27 | Skinner, Steven; Kirschvink, Joseph |
Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica |
["POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))"] | ["POINT(-57.55 -64.1)"] | false | false | |
NBP1502A Cruise Core Data
|
1246353 |
2018-02-05 | Simkins, Lauren; Anderson, John; Prothro, Lindsay |
Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. |
Dataset includes details of cores collected as part of cruise NBP1502A, a list of radiocarbon-dated samples and samples to be radiocarbon-dated, and grain-size data from select NBP1502A cores. | ["POLYGON((-180 -74.37,-178.85 -74.37,-177.7 -74.37,-176.55 -74.37,-175.4 -74.37,-174.25 -74.37,-173.1 -74.37,-171.95 -74.37,-170.8 -74.37,-169.65 -74.37,-168.5 -74.37,-168.5 -74.747,-168.5 -75.124,-168.5 -75.501,-168.5 -75.878,-168.5 -76.255,-168.5 -76.632,-168.5 -77.009,-168.5 -77.386,-168.5 -77.763,-168.5 -78.14,-169.65 -78.14,-170.8 -78.14,-171.95 -78.14,-173.1 -78.14,-174.25 -78.14,-175.4 -78.14,-176.55 -78.14,-177.7 -78.14,-178.85 -78.14,180 -78.14,178.48 -78.14,176.96 -78.14,175.44 -78.14,173.92 -78.14,172.4 -78.14,170.88 -78.14,169.36 -78.14,167.84 -78.14,166.32 -78.14,164.8 -78.14,164.8 -77.763,164.8 -77.386,164.8 -77.009,164.8 -76.632,164.8 -76.255,164.8 -75.878,164.8 -75.501,164.8 -75.124,164.8 -74.747,164.8 -74.37,166.32 -74.37,167.84 -74.37,169.36 -74.37,170.88 -74.37,172.4 -74.37,173.92 -74.37,175.44 -74.37,176.96 -74.37,178.48 -74.37,-180 -74.37))"] | ["POINT(178.15 -76.255)"] | false | false |
DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data
|
1341669 |
2018-02-03 | DeMaster, David |
Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change |
This file has C-14 data from the organic matter fraction of Antarctic marine sediments, collected from the collapsed Larsen Ice Shelf and the West Antarctic Peninsula | ["POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))"] | ["POINT(-64 -65)"] | false | false |
LARISSA: Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula
|
0732917 |
2017-12-17 | McCormick, Michael |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems. |
Ice-shelf loss along the east coast of the Antarctic Peninsula over recent decades has brought new sources of carbon and energy to the marine benthos likely affecting sediment geochemistry and microbial community composition. To better understand the long-term effects of ice-shelf loss on benthic microbial communities, we conducted a five-station survey along a 160 km transect following the historic path of retreat of the Larsen A ice shelf. All microbial community sequence data is publicly available through the Metagenomics Analysis Server at Argonne National Laboratory (MG-RAST). The project title is "Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula". A key word search using terms from this title at the MG-RAST portal (http://metagenomics.anl.gov/) will return the complete sample list. This submitted dataset summarizes the measured environmental parameters for these same samples (lat., long., water depth, sediment depth, pH, alkalinity, dissolved oxygen, silicate, phosphate, nitrate, nitrite, and ammonium). | ["POLYGON((299.4 -63.1,299.92 -63.1,300.44 -63.1,300.96 -63.1,301.48 -63.1,302 -63.1,302.52 -63.1,303.04 -63.1,303.56 -63.1,304.08 -63.1,304.6 -63.1,304.6 -63.29,304.6 -63.48,304.6 -63.67,304.6 -63.86,304.6 -64.05,304.6 -64.24,304.6 -64.43,304.6 -64.62,304.6 -64.81,304.6 -65,304.08 -65,303.56 -65,303.04 -65,302.52 -65,302 -65,301.48 -65,300.96 -65,300.44 -65,299.92 -65,299.4 -65,299.4 -64.81,299.4 -64.62,299.4 -64.43,299.4 -64.24,299.4 -64.05,299.4 -63.86,299.4 -63.67,299.4 -63.48,299.4 -63.29,299.4 -63.1))"] | ["POINT(-58 -64.05)"] | false | false |
Sabrina Coast mooring data - sediment trap mooring 2014
|
1143834 |
2017-11-15 | Huber, Bruce |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Time series of temperature and salinity from a sediment trap mooring deployed during NBP1402 on 04 March 2014 at 66S 11, 122 E 30.2, depth 547 m. The mooring was recovered from Aurora Australis on 26 December 2014 | ["POINT(120.5 -66.2)"] | ["POINT(120.5 -66.2)"] | false | false |
Images of Fossil Plants of Antarctica
|
1341500 |
2017-11-07 | Ryberg, Patricia |
RUI: Antarctic Paleobotany: Permian Floral Characteristics in a Sedimentary Setting |
Images of Late Permian glossopterid reproductive structures from Allan Hills in the Beardmore Glacier Region of Antarctica. | [] | [] | false | false |
Anvers Trough Foraminifer Stable Isotope data
|
1246378 |
2017-10-25 | Shevenell, Amelia |
Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica |
These are unpublished stable isotope data from a series of sediment cores collected during LMG12-11 and LMG13-11 down the axis of Anvers Trough. These records span the LMG to recent. | ["POLYGON((-65.32 -64.15,-65.309 -64.15,-65.298 -64.15,-65.287 -64.15,-65.276 -64.15,-65.265 -64.15,-65.254 -64.15,-65.243 -64.15,-65.232 -64.15,-65.221 -64.15,-65.21 -64.15,-65.21 -64.186,-65.21 -64.222,-65.21 -64.258,-65.21 -64.294,-65.21 -64.33,-65.21 -64.366,-65.21 -64.402,-65.21 -64.438,-65.21 -64.474,-65.21 -64.51,-65.221 -64.51,-65.232 -64.51,-65.243 -64.51,-65.254 -64.51,-65.265 -64.51,-65.276 -64.51,-65.287 -64.51,-65.298 -64.51,-65.309 -64.51,-65.32 -64.51,-65.32 -64.474,-65.32 -64.438,-65.32 -64.402,-65.32 -64.366,-65.32 -64.33,-65.32 -64.294,-65.32 -64.258,-65.32 -64.222,-65.32 -64.186,-65.32 -64.15))"] | ["POINT(-65.265 -64.33)"] | false | false |
NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data
|
1430550 |
2017-08-18 | Shevenell, Amelia; Smith, Catherine; Domack, Eugene Walter |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Pollen assemblage data for Paleocene to early to middle Eocene sediments collected on Totten continental shelf, East Antarctica. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"] | ["POINT(120.5 -68)"] | false | false |
NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data
|
1430550 |
2017-08-18 | Smith, Catherine; Shevenell, Amelia; Domack, Eugene Walter |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Bulk sediment carbon and nitrogen data data for Paleocene sediments collected on Totten continental shelf, East Antarctica. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"] | ["POINT(120.5 -68)"] | false | false |
NBP14-02 JPC-55 foraminifer assemblage data
|
1143836 |
2017-08-18 | Shevenell, Amelia; Leventer, Amy |
Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics |
Foraminifer assemblage data for Paleocene sediments collected on Totten continental shelf, East Antarctica. | ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"] | ["POINT(120.5 -68)"] | false | false |
Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins
|
1043554 |
2016-11-09 | Willenbring, Jane |
Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins |
The PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events. This study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K-12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete. | ["POINT(161.5 -77.5)"] | ["POINT(161.5 -77.5)"] | false | false |
Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD)
|
0839059 |
2016-01-01 | Powell, Ross |
Collaborative Research: Integrative Study of Marine Ice Sheet Stability & Subglacial Life Habitats in W Antarctica - Lake & Ice Stream Subglacial Access Research Drilling (LISSARD) |
The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF's Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars. | ["POLYGON((-168.7 -82.3,-168.69 -82.3,-168.68 -82.3,-168.67 -82.3,-168.66 -82.3,-168.65 -82.3,-168.64 -82.3,-168.63 -82.3,-168.62 -82.3,-168.61 -82.3,-168.6 -82.3,-168.6 -82.31,-168.6 -82.32,-168.6 -82.33,-168.6 -82.34,-168.6 -82.35,-168.6 -82.36,-168.6 -82.37,-168.6 -82.38,-168.6 -82.39,-168.6 -82.4,-168.61 -82.4,-168.62 -82.4,-168.63 -82.4,-168.64 -82.4,-168.65 -82.4,-168.66 -82.4,-168.67 -82.4,-168.68 -82.4,-168.69 -82.4,-168.7 -82.4,-168.7 -82.39,-168.7 -82.38,-168.7 -82.37,-168.7 -82.36,-168.7 -82.35,-168.7 -82.34,-168.7 -82.33,-168.7 -82.32,-168.7 -82.31,-168.7 -82.3))"] | ["POINT(-168.65 -82.35)"] | false | false |
Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica
|
0839031 |
2016-01-01 | Severinghaus, Jeffrey P. |
Collaborative Research: A "Horizontal Ice Core" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica |
This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the 'clathrate hypothesis' that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (>1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a 'horizontal ice core' would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica. | ["POINT(161.71965 -77.76165)"] | ["POINT(161.71965 -77.76165)"] | false | false |
Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica
|
0944282 |
2016-01-01 | Hasiotis, Stephen |
Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica |
This proposal will study the diversity, abundance, and tiering patterns of ichnofossils in continental and marine deposits of the Beacon Supergroup in the Beardmore Glacier Area (BGA). The PIs will focus on continental strata that contain a variety of ichnofossils and paleosols. Ichnofossils will be evaluated for their architectural and surficial morphologies, and will be compared to modern and ancient traces to interpret the tracemaker behavior and paleoenvironmental setting. Distribution of ichnofossils within these units may indicate the effect of lateral variability of pedogenesis, the magnitude and frequency of depositional events, and the amount of moisture within the sediment, as well as the effects of climate change. The paleoclimatic significance of ichnofossils will be determined by comparing the burrow size, occurrence, tiering, and pedogenic significance of ichnofossils in measured sections of stratigraphic units deposited during global warming and cooling episodes. Comparisons will be made between BGA formations to stratigraphically equivalent rocks deposited at low paleolatitudes with previously determined paleoclimatic settings. The objectives of this project are to address two major questions: what differences existed in ichnodiversity, abundance, and tiering in marine and continental deposits between high- and low-paleolatitudes, and was there a dearth of habitat usage in continental deposits during the late Paleozoic and Mesozoic, particularly in fluvial and lacustrine environments compared to the habitat usage in the marine realm at that time? This study will enhance the ability to interpret paleoenvironments to the subenvironmental scale, understand the evolution of soil biota and ecosystems at high paleolatitudes, determine the role of organisms in soil formation at high paleolatitudes, explore the effects of climate change on the body size and diversity of organisms in the soil communities, and develop new tools to interpret paleoclimate in high latitudes. There is a strong education component associated with this proposal. | ["POINT(175 -86)"] | ["POINT(175 -86)"] | false | false |
Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES)
|
0839107 |
2016-01-01 | Powell, Ross |
Collaborative Research: Integrative Study of Marine Ice Sheet Stability & Subglacial Life Habitats in W Antarctica - Lake & Ice Stream Subglacial Access Research Drilling (LISSARD) |
The RAGES project (Robotic Access to Grounding zones for Exploration and Science) is one of three research components of the WISSARD (Whillans Ice Stream Subglacial Access Research Drilling) integrative initiative that is being funded by the Antarctic Integrated System Science Program of NSF's Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The RAGES component of WISSARD concentrates on the stability of ice stream grounding zones (GZ), the area where the ice, ocean waters and glacial and sea floor sediment interact. Based on our present limited data and modeling efforts, GZs can be perturbed by (i) internal ice stream dynamics, (ii) filling/draining cycles of subglacial lakes, (iii) increased melting by warming ocean waters, and/or (iv) rates of subglacial sediment (till) supply to the GZ. GZs are seen as high priority targets to investigate due to their unknown contributions to ice sheet stability under future global warming scenarios. The three main science goals for RAGES are to assess: (a) West Antarctic Ice Sheet (WAIS) stability relative to the magnitudes of the four main variables listed above; (b) the degree to which grounding-zone sedimentary systems house important records of past WAIS dynamics; and (c) the importance of microbial activity and subglacial geochemical weathering in supplying nutrients to the WAIS grounding zone, the Ross Ice Shelf (RIS) cavity, and the highly productive Southern Ocean that may ultimately influence global biogeochemical cycles. The RAGES field sampling plan integrates surface geophysical surveys with borehole and subglacial sampling and measurements. The boreholes provide: (1) samples of subglacial water, sediments, and basal ice for biological, geochemical, glaciological, sedimentological, and micropaleontological analyses; (2) measures of subglacial and sub-ice-shelf cavity physical and chemical conditions and their spatial variability; and (3) data on sediment types, state and change of the subglacial water discharge, oceanography, and basal ice at the grounding line and within the nearby sub-ice-shelf cavity. Unique tools to be deployed include a multisensor Sub-Ice ROVer (Remotely Operated Vehicle) and long-term, sub-ice oceanographic moorings. The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. The RAGES project represents a significant advance in polar technology by incorporating the use of complex new instrumentation like the Sub-Ice ROVer and subglacial ocean/lake mooring systems. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars. | ["POLYGON((-163.7 -84,-163.68 -84,-163.66 -84,-163.64 -84,-163.62 -84,-163.6 -84,-163.58 -84,-163.56 -84,-163.54 -84,-163.52 -84,-163.5 -84,-163.5 -84.05,-163.5 -84.1,-163.5 -84.15,-163.5 -84.2,-163.5 -84.25,-163.5 -84.3,-163.5 -84.35,-163.5 -84.4,-163.5 -84.45,-163.5 -84.5,-163.52 -84.5,-163.54 -84.5,-163.56 -84.5,-163.58 -84.5,-163.6 -84.5,-163.62 -84.5,-163.64 -84.5,-163.66 -84.5,-163.68 -84.5,-163.7 -84.5,-163.7 -84.45,-163.7 -84.4,-163.7 -84.35,-163.7 -84.3,-163.7 -84.25,-163.7 -84.2,-163.7 -84.15,-163.7 -84.1,-163.7 -84.05,-163.7 -84))"] | ["POINT(-163.6 -84.25)"] | false | false |
Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica
|
1303896 |
2015-01-01 | Kirschvink, Joseph |
Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica |
The PI will collect samples to extend the magneto-stratigraphic record of late Cretaceous sediments of the James Ross Basin, Antarctica. RAPID support will allow him to take advantage of an invitation from the Instituto Antartico Argentino (IAA) to participate on an excursion to James Ross Island in the Antarctic Peninsula. The PI hopes to collect samples that will refine the position of several geomagnetic reversals between the end of the Cretaceous long normal Chron and the lower portion of Chron 31R. The Brandy Bay locality targeted by this expedition is the best place in the basin for calibrating the biostratigraphic position of the top of the Cretaceous Long Normal Chron, which is one of the most reliable correlation horizons in the entire Geological Time Scale. The top of the Cretaceous long normal Chron is not properly correlated to southern hemisphere biostratigraphy. Locating this event will be a major addition to understanding geological time. This expedition will provide opportunities for an undergraduate student. This project is based on a productive collaboration with an Argentine scientist. | ["POLYGON((-57 -63,-56.9 -63,-56.8 -63,-56.7 -63,-56.6 -63,-56.5 -63,-56.4 -63,-56.3 -63,-56.2 -63,-56.1 -63,-56 -63,-56 -63.2,-56 -63.4,-56 -63.6,-56 -63.8,-56 -64,-56 -64.2,-56 -64.4,-56 -64.6,-56 -64.8,-56 -65,-56.1 -65,-56.2 -65,-56.3 -65,-56.4 -65,-56.5 -65,-56.6 -65,-56.7 -65,-56.8 -65,-56.9 -65,-57 -65,-57 -64.8,-57 -64.6,-57 -64.4,-57 -64.2,-57 -64,-57 -63.8,-57 -63.6,-57 -63.4,-57 -63.2,-57 -63))"] | ["POINT(-56.5 -64)"] | false | false |
Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)
|
1043740 |
2014-01-01 | Lenczewski, Melissa |
Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL) |
The PI proposes to utilize computer models used by hydrogeologists to establish the fate and transport of contamination and determine the extent of drilling fluid contamination in the ANDRILL SMS core. For these models, previously collected logs of lithology, porosity, fracture density, fracture type, fracture orientation, drilling fluid loss, drilling fluid characteristics and temperature will be used as input parameters. In addition, biodegradation and sorption constants for the drilling fluid will be determined and incorporated into the models. Samples of drilling fluids used during coring as well as the return fluids were collected at the drill site using standard microbiological sampling techniques. Fluids will be tested at in situ temperatures under aerobic and anaerobic conditions to determine biodegradation constants. Sorption will be determined between the drilling fluids and core samples using standard isotherm methods. Geochemical and microbial fingerprints of the fluids and the changes during biodegradation will determine the potential impact of the drilling fluids on the isolated microbial communities and the geochemistry within various subsurface lithologic units beneath the southern McMurdo Sound in Antarctica. The results of this study could potentially provide guidelines on developing less detrimental methods for future exploration, if deemed necessary through this research. This proposed project will train a graduate student. The methods developed for analyses of samples in this project will serve as a guide for future studies of similar interest and will improve the understanding of ecological impacts of geologic drilling in Antarctica. The results of this study will be used as a reference for comparison with future studies examining newly developed, and improved, sample collection methods in future exploratory drilling projects in pristine environments. The PI is new to Antarctic research. | ["POLYGON((165 -77.5,165.3 -77.5,165.6 -77.5,165.9 -77.5,166.2 -77.5,166.5 -77.5,166.8 -77.5,167.1 -77.5,167.4 -77.5,167.7 -77.5,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,168 -78.1,168 -78.2,168 -78.3,168 -78.4,168 -78.5,167.7 -78.5,167.4 -78.5,167.1 -78.5,166.8 -78.5,166.5 -78.5,166.2 -78.5,165.9 -78.5,165.6 -78.5,165.3 -78.5,165 -78.5,165 -78.4,165 -78.3,165 -78.2,165 -78.1,165 -78,165 -77.9,165 -77.8,165 -77.7,165 -77.6,165 -77.5))"] | ["POINT(166.5 -78)"] | false | false |
Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains
|
1354231 |
2014-01-01 | Kowalewski, Douglas |
Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains |
Intellectual Merit: Neogene sediment records recovered by ANDRILL suggest multiple events of open water conditions and elevated sea surface temperatures at times when terrestrial data from the McMurdo Dry Valleys indicate hyper arid, cold, desert conditions. Interpretation of the ANDRILL data suggests the West Antarctic Ice Sheet is highly sensitive to changes in Pliocene sea surface temperatures and this conclusion has been supported by recent Global Circulation Model results for the early to mid Pliocene. The PIs propose to model paleo-ice configurations and warm orbits associated with a WAIS collapse to assess potential climate change in East Antarctica. During such episodes of polar warmth they propose to answer: What is the limit of ablation along the East Antarctic Ice Sheet?; Are relict landforms in the Dry Valleys susceptible to modification from increase in maximum summertime temperatures?; and Is there sufficient increase in minimum wintertime temperatures to sustain a tundra environment in the Dry Valleys? Integration of depositional records and model outputs have the potential to test the performance of numerical models currently under development as part of ANDRILL; reconcile inconsistencies between marine and terrestrial paleoclimate records in high Southern Latitudes; and improve understanding of Antarctic climate and ice volume sensitivity to forcing for both the East Antarctic and West Antarctic Ice Sheets. Broader impacts: Results from this study have the potential to be used widely by the research community. Outreach to local elementary schools from other funded efforts will continue and be extended to homeschooled students. A Post Doc will be supported as part of this award. | ["POLYGON((-160 -70,-156 -70,-152 -70,-148 -70,-144 -70,-140 -70,-136 -70,-132 -70,-128 -70,-124 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-124 -85,-128 -85,-132 -85,-136 -85,-140 -85,-144 -85,-148 -85,-152 -85,-156 -85,-160 -85,-160 -83.5,-160 -82,-160 -80.5,-160 -79,-160 -77.5,-160 -76,-160 -74.5,-160 -73,-160 -71.5,-160 -70))"] | ["POINT(-140 -77.5)"] | false | false |
Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems
|
0732983 |
2014-01-01 | Vernet, Maria |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems. A profound transformation in ecosystem structure and function is occurring in coastal waters of the western Weddell Sea, with the collapse of the Larsen B ice shelf. This transformation appears to be yielding a redistribution of energy flow between chemoautotrophic and photosynthetic production, and to be causing the rapid demise of the extraordinary seep ecosystem discovered beneath the ice shelf. This event provides an ideal opportunity to examine fundamental aspects of ecosystem transition associated with climate change. We propose to test the following hypotheses to elucidate the transformations occurring in marine ecosystems as a consequence of the Larsen B collapse: (1) The biogeographic isolation and sub-ice shelf setting of the Larsen B seep has led to novel habitat characteristics, chemoautotrophically dependent taxa and functional adaptations. (2) Benthic communities beneath the former Larsen B ice shelf are fundamentally different from assemblages at similar depths in the Weddell sea-ice zone, and resemble oligotrophic deep-sea communities. Larsen B assemblages are undergoing rapid change. (3) The previously dark, oligotrophic waters of the Larsen B embayment now support a thriving phototrophic community, with production rates and phytoplankton composition similar to other productive areas of the Weddell Sea. To document rapid changes occurring in the Larsen B ecosystem, we will use a remotely operated vehicle, shipboard samplers, and moored sediment traps. We will characterize microbial, macrofaunal and megafaunal components of the seep community; evaluate patterns of surface productivity, export flux, and benthic faunal composition in areas previously covered by the ice shelf, and compare these areas to the open sea-ice zone. These changes will be placed within the geological, glaciological and climatological context that led to ice-shelf retreat, through companion research projects funded in concert with this effort. Together these projects will help predict the likely consequences of ice-shelf collapse to marine ecosystems in other regions of Antarctica vulnerable to climate change. The research features international collaborators from Argentina, Belgium, Canada, Germany, Spain and the United Kingdom. The broader impacts include participation of a science writer; broadcast of science segments by members of the Jim Lehrer News Hour (Public Broadcasting System); material for summer courses in environmental change; mentoring of graduate students and postdoctoral fellows; and showcasing scientific activities and findings to students and public through podcasts. | ["POLYGON((-66 -62,-65.3 -62,-64.6 -62,-63.9 -62,-63.2 -62,-62.5 -62,-61.8 -62,-61.1 -62,-60.4 -62,-59.7 -62,-59 -62,-59 -62.8,-59 -63.6,-59 -64.4,-59 -65.2,-59 -66,-59 -66.8,-59 -67.6,-59 -68.4,-59 -69.2,-59 -70,-59.7 -70,-60.4 -70,-61.1 -70,-61.8 -70,-62.5 -70,-63.2 -70,-63.9 -70,-64.6 -70,-65.3 -70,-66 -70,-66 -69.2,-66 -68.4,-66 -67.6,-66 -66.8,-66 -66,-66 -65.2,-66 -64.4,-66 -63.6,-66 -62.8,-66 -62))"] | ["POINT(-62.5 -66)"] | false | false |
Ocean-Ice Interaction in the Amundsen Sea Sector of West Antarctica
|
0732804 |
2014-01-01 | McPhee, Miles G. |
Collaborative Research; IPY: Ocean-Ice Interaction in the Amundsen Sea sector of West Antarctica |
The Office of Polar Programs, Antarctic Integrated and System Science Program has made this award to support an interdisciplinary study of the effects of the ocean on the stability of glacial ice in the most dynamic region the West Antarctic Ice Sheet, namely the Pine Island Glacier in the Amundsen Sea Embayment. The collaborative project builds on the knowledge gained by the highly successful West Antarctic Ice Sheet program and is being jointly sponsored with NASA. Recent observations indicate a significant ice loss, equivalent to 10% of the ongoing increase in sea-level rise, in this region. These changes are largest along the coast and propagate rapidly inland, indicating the critical impact of the ocean on ice sheet stability in the region. While a broad range of remote sensing and ground-based instrumentation is available to characterize changes of the ice surface and internal structure (deformation, ice motion, melt) and the shape of the underlying sediment and rock bed, instrumentation has yet to be successfully deployed for observing boundary layer processes of the ocean cavity which underlies the floating ice shelf and where rapid melting is apparently occurring. Innovative, mini ocean sensors that can be lowered through boreholes in the ice shelf (about 500 m thick) will be developed and deployed to automatically provide ocean profiling information over at least three years. Their data will be transmitted through a conducting cable frozen in the borehole to the surface where it will be further transmitted via satellite to a laboratory in the US. Geophysical and remote sensing methods (seismic, GPS, altimetry, stereo imaging, radar profiling) will be applied to map the geometry of the ice shelf, the shape of the sub ice-shelf cavity, the ice surface geometry and deformations within the glacial ice. To integrate the seismic, glaciological and oceanographic observations, a new 3-dimensional coupled ice-ocean model is being developed which will be the first of its kind. NASA is supporting satellite based research and the deployment of a robotic-camera system to explore the environment in the ocean cavity underlying the ice shelf and NSF is supporting all other aspects of this study. Broader impacts: This project is motivated by the potential societal impacts of rapid sea level rise and should result in critically needed improvements in characterizing and predicting the behavior of coupled ocean-ice systems. It is a contribution to the International Polar Year and was endorsed by the International Council for Science as a component of the 'Multidisciplinary Study of the Amundsen Sea Embayment' proposal #258 of the honeycomb of endorsed IPY activities. The research involves substantial international partnerships with the British Antarctic Survey and the University of Bristol in the UK. The investigators will partner with the previously funded 'Polar Palooza' education and outreach program in addition to undertaking a diverse set of outreach activities of their own. Eight graduate students and one undergraduate as well as one post doc will be integrated into this research project. | ["POINT(166.25 -77.42)"] | ["POINT(166.25 -77.42)"] | false | false |
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export
|
1043690 |
2014-01-01 | Haji-Sheikh, Michael; Scherer, Reed Paul |
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export |
Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material. Broader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines
|
0944475 |
2014-01-01 | Kaplan, Michael |
Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines |
Intellectual Merit: The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica's inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed <2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. Broader Impact: The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences. | ["POLYGON((-180 -84.1,-176.97 -84.1,-173.94 -84.1,-170.91 -84.1,-167.88 -84.1,-164.85 -84.1,-161.82 -84.1,-158.79 -84.1,-155.76 -84.1,-152.73 -84.1,-149.7 -84.1,-149.7 -84.43,-149.7 -84.76,-149.7 -85.09,-149.7 -85.42,-149.7 -85.75,-149.7 -86.08,-149.7 -86.41,-149.7 -86.74,-149.7 -87.07,-149.7 -87.4,-152.73 -87.4,-155.76 -87.4,-158.79 -87.4,-161.82 -87.4,-164.85 -87.4,-167.88 -87.4,-170.91 -87.4,-173.94 -87.4,-176.97 -87.4,180 -87.4,178.12 -87.4,176.24 -87.4,174.36 -87.4,172.48 -87.4,170.6 -87.4,168.72 -87.4,166.84 -87.4,164.96 -87.4,163.08 -87.4,161.2 -87.4,161.2 -87.07,161.2 -86.74,161.2 -86.41,161.2 -86.08,161.2 -85.75,161.2 -85.42,161.2 -85.09,161.2 -84.76,161.2 -84.43,161.2 -84.1,163.08 -84.1,164.96 -84.1,166.84 -84.1,168.72 -84.1,170.6 -84.1,172.48 -84.1,174.36 -84.1,176.24 -84.1,178.12 -84.1,-180 -84.1))"] | ["POINT(-174.25 -85.75)"] | false | false |
History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris
|
0944489 |
2014-01-01 | Williams, Trevor; Hemming, Sidney R. |
History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris |
Intellectual Merit: The PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Adelie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that indicate ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization. Broader impacts: The data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences | ["POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))"] | ["POINT(54 -68)"] | false | false |
The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter
|
1039365 |
2013-01-01 | Rimmer, Susan |
Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter |
This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. The broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming. | [] | [] | false | false |
Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica
|
0739698 0739681 |
2013-01-01 | Murray, Alison |
Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica |
Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake's history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities. | ["POINT(161.931 -77.3885)"] | ["POINT(161.931 -77.3885)"] | false | false |
Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology
|
0838722 |
2012-01-01 | Gehrels, George; Reiners, Peter; Thomson, Stuart |
Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology |
Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion. | ["POLYGON((61.9 -67.28,63.218 -67.28,64.536 -67.28,65.854 -67.28,67.172 -67.28,68.49 -67.28,69.808 -67.28,71.126 -67.28,72.444 -67.28,73.762 -67.28,75.08 -67.28,75.08 -67.922,75.08 -68.564,75.08 -69.206,75.08 -69.848,75.08 -70.49,75.08 -71.132,75.08 -71.774,75.08 -72.416,75.08 -73.058,75.08 -73.7,73.762 -73.7,72.444 -73.7,71.126 -73.7,69.808 -73.7,68.49 -73.7,67.172 -73.7,65.854 -73.7,64.536 -73.7,63.218 -73.7,61.9 -73.7,61.9 -73.058,61.9 -72.416,61.9 -71.774,61.9 -71.132,61.9 -70.49,61.9 -69.848,61.9 -69.206,61.9 -68.564,61.9 -67.922,61.9 -67.28))"] | ["POINT(68.49 -70.49)"] | false | false |
Thermochronologic and modelling test for a Mesozoic West Antarctic Plateau
|
0739781 |
2012-01-01 | Blythe, Ann Elizabeth; Huerta, Audrey D. |
Collaborative Research: Thermochronologic and modelling test for a Mesozoic West Antarctic Plateau |
This project studies formation of the TransAntarctic Mountains (TAM) through numerical modeling based on cooling histories of apatite mineral grains. The TAM are the highest and longest rift-related mountain range in the world. Various models for their uplift have been proposed, the most provocative of which is that they are not uplifted, but instead are the eroded remnant of a plateau. This project evaluates that hypothesis by collecting apatites from around Byrd Glacier for fission track thermochronology. Results will be combined with a kinematic and thermal model to determine the TAM's structural evolution. The plateau model, if correct, implies that the Byrd Glacier originated not as a glacier-carved valley through the TAM, but as a river system flowing in the opposite direction. Given that the Byrd Glacier is a key drainage for the East Antarctic ice sheet, this result has important implications for ice sheet models and interpretation of both regional geology and sediment records. The main broader impacts are undergraduate research and a new collaboration between a primarily undergraduate and a research institution. Students will be involved in the field program, sample analyses, and numerical modeling. | ["POLYGON((155.77667 -79.793335,156.208836 -79.793335,156.641002 -79.793335,157.073168 -79.793335,157.505334 -79.793335,157.9375 -79.793335,158.369666 -79.793335,158.801832 -79.793335,159.233998 -79.793335,159.666164 -79.793335,160.09833 -79.793335,160.09833 -79.8578345,160.09833 -79.922334,160.09833 -79.9868335,160.09833 -80.051333,160.09833 -80.1158325,160.09833 -80.180332,160.09833 -80.2448315,160.09833 -80.309331,160.09833 -80.3738305,160.09833 -80.43833,159.666164 -80.43833,159.233998 -80.43833,158.801832 -80.43833,158.369666 -80.43833,157.9375 -80.43833,157.505334 -80.43833,157.073168 -80.43833,156.641002 -80.43833,156.208836 -80.43833,155.77667 -80.43833,155.77667 -80.3738305,155.77667 -80.309331,155.77667 -80.2448315,155.77667 -80.180332,155.77667 -80.1158325,155.77667 -80.051333,155.77667 -79.9868335,155.77667 -79.922334,155.77667 -79.8578345,155.77667 -79.793335))"] | ["POINT(157.9375 -80.1158325)"] | false | false |
Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology
|
0838729 |
2011-01-01 | Hemming, Sidney R. |
Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology |
Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion. | ["POLYGON((-67.2 -58,-43.98 -58,-20.76 -58,2.46 -58,25.68 -58,48.9 -58,72.12 -58,95.34 -58,118.56 -58,141.78 -58,165 -58,165 -59.2,165 -60.4,165 -61.6,165 -62.8,165 -64,165 -65.2,165 -66.4,165 -67.6,165 -68.8,165 -70,141.78 -70,118.56 -70,95.34 -70,72.12 -70,48.9 -70,25.68 -70,2.46 -70,-20.76 -70,-43.98 -70,-67.2 -70,-67.2 -68.8,-67.2 -67.6,-67.2 -66.4,-67.2 -65.2,-67.2 -64,-67.2 -62.8,-67.2 -61.6,-67.2 -60.4,-67.2 -59.2,-67.2 -58))"] | ["POINT(48.9 -64)"] | false | false |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals
|
0902957 |
2011-01-01 | Robinson, Laura |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals |
The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column. | ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"] | ["POINT(-52.75 -58)"] | false | false |
Development of Quantitative Weathering Indicators in Proximal Alluvial Sediments to Assess Glacial Activity in the Rock Record
|
0842639 |
2011-01-01 | Soreghan, Gerilyn; Elwood Madden, Megan |
Development of Quantitative Weathering Indicators in Proximal Alluvial Sediments to Assess Glacial Activity in the Rock Record |
The proposed research seeks to test the hypothesis that chemical and physical weathering in proximal alluvial systems will show systematic and measurable variations between glacial and nonglacial systems. To accomplish this, the investigation will attempt to quantify the natural variation of chemical and physical weathering in granitoid-sourced proximal alluvial sediments in end-member glacial and nonglacial systems, when other, 'non-climatic' factors (e.g. provenance, drainage basin area and relief, sample grain size, sediment facies) are controlled. If chemical weathering in the proposed hot-humid, hot-arid, hot semi-arid nonglacial systems and the cool-wet, cold semi-arid, and cold-arid glacial systems show systematic variations, then chemical indices may be used to help differentiate paleoclimatic conditions. Continued reliance on students provides a broader impact of this proposed research and firmly grounds this effort in its educational mission. | ["POLYGON((-163.12865 -77.41693,-163.06062 -77.41693,-162.99259 -77.41693,-162.92456 -77.41693,-162.85653 -77.41693,-162.7885 -77.41693,-162.72047 -77.41693,-162.65244 -77.41693,-162.58441 -77.41693,-162.51638 -77.41693,-162.44835 -77.41693,-162.44835 -77.445495,-162.44835 -77.47406,-162.44835 -77.502625,-162.44835 -77.53119,-162.44835 -77.559755,-162.44835 -77.58832,-162.44835 -77.616885,-162.44835 -77.64545,-162.44835 -77.674015,-162.44835 -77.70258,-162.51638 -77.70258,-162.58441 -77.70258,-162.65244 -77.70258,-162.72047 -77.70258,-162.7885 -77.70258,-162.85653 -77.70258,-162.92456 -77.70258,-162.99259 -77.70258,-163.06062 -77.70258,-163.12865 -77.70258,-163.12865 -77.674015,-163.12865 -77.64545,-163.12865 -77.616885,-163.12865 -77.58832,-163.12865 -77.559755,-163.12865 -77.53119,-163.12865 -77.502625,-163.12865 -77.47406,-163.12865 -77.445495,-163.12865 -77.41693))"] | ["POINT(-162.7885 -77.559755)"] | false | false |
Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean
|
0636319 |
2011-01-01 | Shaw, Tim; Twining, Benjamin |
Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean |
Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | ["POLYGON((-51.9201 -57.5061,-50.99447 -57.5061,-50.06884 -57.5061,-49.14321 -57.5061,-48.21758 -57.5061,-47.29195 -57.5061,-46.36632 -57.5061,-45.44069 -57.5061,-44.51506 -57.5061,-43.58943 -57.5061,-42.6638 -57.5061,-42.6638 -58.03449,-42.6638 -58.56288,-42.6638 -59.09127,-42.6638 -59.61966,-42.6638 -60.14805,-42.6638 -60.67644,-42.6638 -61.20483,-42.6638 -61.73322,-42.6638 -62.26161,-42.6638 -62.79,-43.58943 -62.79,-44.51506 -62.79,-45.44069 -62.79,-46.36632 -62.79,-47.29195 -62.79,-48.21758 -62.79,-49.14321 -62.79,-50.06884 -62.79,-50.99447 -62.79,-51.9201 -62.79,-51.9201 -62.26161,-51.9201 -61.73322,-51.9201 -61.20483,-51.9201 -60.67644,-51.9201 -60.14805,-51.9201 -59.61966,-51.9201 -59.09127,-51.9201 -58.56288,-51.9201 -58.03449,-51.9201 -57.5061))"] | ["POINT(-47.29195 -60.14805)"] | false | false |
Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean
|
0636543 |
2010-01-01 | Murray, Alison |
Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean |
Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | ["POLYGON((-51.98403 -57.58068,-51.042765 -57.58068,-50.1015 -57.58068,-49.160235 -57.58068,-48.21897 -57.58068,-47.277705 -57.58068,-46.33644 -57.58068,-45.395175 -57.58068,-44.45391 -57.58068,-43.512645 -57.58068,-42.57138 -57.58068,-42.57138 -58.10845,-42.57138 -58.63622,-42.57138 -59.16399,-42.57138 -59.69176,-42.57138 -60.21953,-42.57138 -60.7473,-42.57138 -61.27507,-42.57138 -61.80284,-42.57138 -62.33061,-42.57138 -62.85838,-43.512645 -62.85838,-44.45391 -62.85838,-45.395175 -62.85838,-46.33644 -62.85838,-47.277705 -62.85838,-48.21897 -62.85838,-49.160235 -62.85838,-50.1015 -62.85838,-51.042765 -62.85838,-51.98403 -62.85838,-51.98403 -62.33061,-51.98403 -61.80284,-51.98403 -61.27507,-51.98403 -60.7473,-51.98403 -60.21953,-51.98403 -59.69176,-51.98403 -59.16399,-51.98403 -58.63622,-51.98403 -58.10845,-51.98403 -57.58068))"] | ["POINT(-47.277705 -60.21953)"] | false | false |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes
|
0538580 |
2010-01-01 | van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R. |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes |
This project studies sediment from the ocean floor to understand Antarctica's geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work's central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry. | ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"] | ["POINT(120 -65)"] | false | false |
R/V Nathaniel B. Palmer NBP0603 - Paleohistory of the Larsen Ice Shelf System
|
0338163 |
2010-01-01 | Domack, Eugene Walter |
Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II |
The NSF-supported research icebreaker Nathaniel B. Palmer operates year-round in support of the U.S. Antarctic Program, carrying out global change studies in biological, chemical, physical, and oceanographic disciplines. This data set consists of underway data from leg NBP0603 on the R/V Nathaniel B. Palmer. This leg started at Punta Arenas, Chile and ended at Punta Arenas, Chile. | ["POLYGON((-70.90391 -52.35262,-68.130917 -52.35262,-65.357924 -52.35262,-62.584931 -52.35262,-59.811938 -52.35262,-57.038945 -52.35262,-54.265952 -52.35262,-51.492959 -52.35262,-48.719966 -52.35262,-45.946973 -52.35262,-43.17398 -52.35262,-43.17398 -53.75776,-43.17398 -55.1629,-43.17398 -56.56804,-43.17398 -57.97318,-43.17398 -59.37832,-43.17398 -60.78346,-43.17398 -62.1886,-43.17398 -63.59374,-43.17398 -64.99888,-43.17398 -66.40402,-45.946973 -66.40402,-48.719966 -66.40402,-51.492959 -66.40402,-54.265952 -66.40402,-57.038945 -66.40402,-59.811938 -66.40402,-62.584931 -66.40402,-65.357924 -66.40402,-68.130917 -66.40402,-70.90391 -66.40402,-70.90391 -64.99888,-70.90391 -63.59374,-70.90391 -62.1886,-70.90391 -60.78346,-70.90391 -59.37832,-70.90391 -57.97318,-70.90391 -56.56804,-70.90391 -55.1629,-70.90391 -53.75776,-70.90391 -52.35262))"] | ["POINT(-57.038945 -59.37832)"] | false | false |
Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates
|
0338087 |
2010-01-01 | Scheltema, Rudolf |
Collaborative Research: Relevance of Planktonic Larval Dispersal to Endemism and Biogeography of Antarctic Benthic Invertebrates |
Because of extreme isolation of the Antarctic continent since the Early Oligocene, one expects a unique invertebrate benthic fauna with a high degree of endemism. Yet some invertebrate taxa that constitute important ecological components of sedimentary benthic communities include more than 40 percent non-endemic species (e.g., benthic polychaetes). To account for non-endemic species, intermittent genetic exchange must occur between Antarctic and other (e.g. South American) populations. The most likely mechanism for such gene flow, at least for in-faunal and mobile macrobenthos, is dispersal of planktonic larvae across the sub- Antarctic and Antarctic polar fronts. To test for larval dispersal as a mechanism of maintaining genetic continuity across polar fronts, the scientists propose to (1) take plankton samples along transects across Drake passage during both the austral summer and winter seasons while concurrently collecting the appropriate hydrographic data. Such data will help elucidate the hydrographic mechanisms that allow dispersal across Drake Passage. Using a molecular phylogenetic approach, they will (2) compare seemingly identical adult forms from Antarctic and South America continents to identify genetic breaks, historical gene flow, and control for the presence of cryptic species. (3) Similar molecular tools will be used to relate planktonic larvae to their adult forms. Through this procedure, they propose to link the larval forms respectively to their Antarctic or South America origins. The proposed work builds on previous research that provides the basis for this effort to develop a synthetic understanding of historical gene flow and present day dispersal mechanism in South American/Drake Passage/Antarctic Peninsular region. Furthermore, this work represents one of the first attempts to examine recent gene flow in Antarctic benthic invertebrates. Graduate students and a postdoctoral fellow will be trained during this research. | ["POLYGON((-70 -53,-68.4 -53,-66.8 -53,-65.2 -53,-63.6 -53,-62 -53,-60.4 -53,-58.8 -53,-57.2 -53,-55.6 -53,-54 -53,-54 -54.5,-54 -56,-54 -57.5,-54 -59,-54 -60.5,-54 -62,-54 -63.5,-54 -65,-54 -66.5,-54 -68,-55.6 -68,-57.2 -68,-58.8 -68,-60.4 -68,-62 -68,-63.6 -68,-65.2 -68,-66.8 -68,-68.4 -68,-70 -68,-70 -66.5,-70 -65,-70 -63.5,-70 -62,-70 -60.5,-70 -59,-70 -57.5,-70 -56,-70 -54.5,-70 -53))"] | ["POINT(-62 -60.5)"] | false | false |
Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change
|
0439906 |
2010-01-01 | Koch, Paul |
Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change |
During previous NSF-sponsored research, the PI's discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island. This project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses. Because of extreme isolation of the Antarctic continent since the Early Oligocene, one expects a unique invertebrate benthic fauna with a high degree of endemism. Yet some invertebrate taxa that constitute important ecological components of sedimentary benthic communities include more than 40 percent non-endemic species (e.g., benthic polychaetes). To account for non-endemic species, intermittent genetic exchange must occur between Antarctic and other (e.g. South American) populations. The most likely mechanism for such gene flow, at least for in-faunal and mobile macrobenthos, is dispersal of planktonic larvae across the sub- Antarctic and Antarctic polar fronts. To test for larval dispersal as a mechanism of maintaining genetic continuity across polar fronts, the scientists propose to (1) take plankton samples along transects across Drake passage during both the austral summer and winter seasons while concurrently collecting the appropriate hydrographic data. Such data will help elucidate the hydrographic mechanisms that allow dispersal across Drake Passage. Using a molecular phylogenetic approach, they will (2) compare seemingly identical adult forms from Antarctic and South America continents to identify genetic breaks, historical gene flow, and control for the presence of cryptic species. (3) Similar molecular tools will be used to relate planktonic larvae to their adult forms. Through this procedure, they propose to link the larval forms respectively to their Antarctic or South America origins. The proposed work builds on previous research that provides the basis for this effort to develop a synthetic understanding of historical gene flow and present day dispersal mechanism in South American/Drake Passage/ Antarctic Peninsular region. Furthermore, this work represents one of the first attempts to examine recent gene flow in Antarctic benthic invertebrates. Graduate students and a postdoctoral fellow will be trained during this research | ["POLYGON((162 -72,162.6 -72,163.2 -72,163.8 -72,164.4 -72,165 -72,165.6 -72,166.2 -72,166.8 -72,167.4 -72,168 -72,168 -72.6,168 -73.2,168 -73.8,168 -74.4,168 -75,168 -75.6,168 -76.2,168 -76.8,168 -77.4,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))"] | ["POINT(165 -75)"] | false | false |
Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean
|
0636730 |
2010-01-01 | Vernet, Maria |
Collaborative Reseach: Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean. |
Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | ["POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))"] | ["POINT(-47.5 -58.5)"] | false | false |
Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean
|
0636723 |
2010-01-01 | Helly, John |
Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean |
Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions: 1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | ["POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))"] | ["POINT(-47.5 -58.5)"] | false | false |
Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?
|
0228842 |
2009-01-01 | Grew, Edward |
Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust? |
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts per million in rocks subjected to conditions of the middle and lower crust, that is, temperatures of 700 degrees C or more in the granulite-facies, which is characterized by very low water activities at pressures of 5 to 10 kbar (18-35 km burial). Devolatization reactions with loss of aqueous fluid and partial melting with removal of melt have been cited as primary causes for boron depletion under granulite-facies conditions. Despite the pervasiveness of both these processes, rocks rich in boron are locally found in the granulite-facies, that is, there are mechanisms for retaining boron during the metamorphic process. The Larsemann Hills, Prydz Bay, Antarctica, are a prime example. More than 20 lenses and layered bodies containing four borosilicate mineral species crop out over a 50 square kilometer area, which thus would be well suited for research on boron-rich granulite-facies metamorphic rocks. While most investigators have focused on the causes for loss of boron, this work will investigate how boron is retained during high-grade metamorphism. Field observations and mapping in the Larsemann Hills, chemical analyses of minerals and their host rocks, and microprobe age dating will be used to identify possible precursors and deduce how the precursor materials recrystallized into borosilicate rocks under granulite-facies conditions. The working hypothesis is that high initial boron content facilitates retention of boron during metamorphism because above a certain threshold boron content, a mechanism 'kicks in' that facilitates retention of boron in metamorphosed rocks. For example, in a rock with large amounts of the borosilicate tourmaline, such as stratabound tourmalinite, the breakdown of tourmaline to melt could result in the formation of prismatine and grandidierite, two borosilicates found in the Larsemann Hills. This situation is rarely observed in rocks with modest boron content, in which breakdown of tourmaline releases boron into partial melts, which in turn remove boron when they leave the system. Stratabound tourmalinite is associated with manganese-rich quartzite, phosphorus-rich rocks and sulfide concentrations that could be diagnostic for recognizing a tourmalinite protolith in a highly metamorphosed complex where sedimentary features have been destroyed by deformation. Because partial melting plays an important role in the fate of boron during metamorphism, our field and laboratory research will focus on the relationship between the borosilicate units, granite pegmatites and other granitic intrusives. The results of our study will provide information on cycling of boron at deeper levels in the Earth's crust and on possible sources of boron for granites originating from deep-seated rocks. An undergraduate student will participate in the electron microprobe age-dating of monazite and xenotime as part of a senior project, thereby integrating the proposed research into the educational mission of the University of Maine. In response to a proposal for fieldwork, the Australian Antarctic Division, which maintains Davis station near the Larsemann Hills, has indicated that they will support the Antarctic fieldwork. | ["POLYGON((76 -69.3,76.05 -69.3,76.1 -69.3,76.15 -69.3,76.2 -69.3,76.25 -69.3,76.3 -69.3,76.35 -69.3,76.4 -69.3,76.45 -69.3,76.5 -69.3,76.5 -69.32,76.5 -69.34,76.5 -69.36,76.5 -69.38,76.5 -69.4,76.5 -69.42,76.5 -69.44,76.5 -69.46,76.5 -69.48,76.5 -69.5,76.45 -69.5,76.4 -69.5,76.35 -69.5,76.3 -69.5,76.25 -69.5,76.2 -69.5,76.15 -69.5,76.1 -69.5,76.05 -69.5,76 -69.5,76 -69.48,76 -69.46,76 -69.44,76 -69.42,76 -69.4,76 -69.38,76 -69.36,76 -69.34,76 -69.32,76 -69.3))"] | ["POINT(76.25 -69.4)"] | false | false |
Occupation History and Diet of Adelie Penguins in the Ross Sea Region
|
0125098 |
2009-01-01 | Emslie, Steven |
Occupation History and Diet of Adelie Penguins in the Ross Sea Region |
This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. Other data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC. | ["POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))"] | ["POINT(55 -75)"] | false | false |
Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica
|
0440954 |
2009-01-01 | Miller, Molly |
Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica |
This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate. In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems. | ["POLYGON((159 -76.61667,159.05 -76.61667,159.1 -76.61667,159.15 -76.61667,159.2 -76.61667,159.25 -76.61667,159.3 -76.61667,159.35 -76.61667,159.4 -76.61667,159.45 -76.61667,159.5 -76.61667,159.5 -76.630003,159.5 -76.643336,159.5 -76.656669,159.5 -76.670002,159.5 -76.683335,159.5 -76.696668,159.5 -76.710001,159.5 -76.723334,159.5 -76.736667,159.5 -76.75,159.45 -76.75,159.4 -76.75,159.35 -76.75,159.3 -76.75,159.25 -76.75,159.2 -76.75,159.15 -76.75,159.1 -76.75,159.05 -76.75,159 -76.75,159 -76.736667,159 -76.723334,159 -76.710001,159 -76.696668,159 -76.683335,159 -76.670002,159 -76.656669,159 -76.643336,159 -76.630003,159 -76.61667))"] | ["POINT(159.25 -76.683335)"] | false | false |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till
|
0538195 |
2009-01-01 | Marone, Chris; Anandakrishnan, Sridhar |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till |
This award supports a project to conduct laboratory experiments and numerical modeling to determine the constitutive properties of subglacial till under dynamic stressing and to test the hypothesis that granular properties of till are sufficient, when coupled elastically to a large ice stream, to reproduce the field observations of triggered slip and subglacial seismicity. Testing will be carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, which will allow both sliding and microstructural processes to be studied in detail. The main focus of the work will be on laboratory measurements. In addition, we will construct continuum models to evaluate whether our results can predict complex ice sheet motions and observed characteristics of subglacial seismicity. In terms of broader impacts, the proposed work will encourage interactions between the rock-mechanics and glaciology communities and will bring together members of different scientific backgrounds and vocabularies, but similar problems and data. The project will train undergraduate and graduate students at Penn State University and the scientists involved plan to give presentations to grade school classes, scout groups, and at community open houses. Results will be presented at professional meetings and will be published in a timely manner. The work will result in a better understanding of glacial motion and the physics of earthquake slip, which is essential for understanding ice sheet dynamics and earthquake hazard. | [] | [] | false | false |
Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica
|
0739452 |
2009-01-01 | Mukhopadhyay, Sujoy |
Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica |
This project seeks to answer a simple question: how old are potholes and related geomorphic features found in the uplands of the McMurdo Dry Valleys, Antarctica? Some research suggests that they are over ten million years old and date the growth of the East Antarctic Ice Sheet, the world's largest. However, some evidence suggests that these are young, erosional features that continuing to evolve to this day. This project uses cosmogenic nuclide dating to determine the age of the pothole floors. The results are important for determining the ice sheet?s history and interpreting the O-isotope record from the marine sediment cores, key records of global climate. Broader impacts include K12 outreach and incorporation of outcomes into university courses. | ["POLYGON((161 -76,161.2 -76,161.4 -76,161.6 -76,161.8 -76,162 -76,162.2 -76,162.4 -76,162.6 -76,162.8 -76,163 -76,163 -76.2,163 -76.4,163 -76.6,163 -76.8,163 -77,163 -77.2,163 -77.4,163 -77.6,163 -77.8,163 -78,162.8 -78,162.6 -78,162.4 -78,162.2 -78,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))"] | ["POINT(162 -77)"] | false | false |
Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores
|
0739496 |
2009-01-01 | Furbish, David; Miller, Molly |
Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores |
This project answers a simple question: why are there so few fossils in sediment cores from Antarctica's continental shelf? Antarctica's benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change. | ["POLYGON((163.41667 -77.33333,163.46667 -77.33333,163.51667 -77.33333,163.56667 -77.33333,163.61667 -77.33333,163.66667 -77.33333,163.71667 -77.33333,163.76667 -77.33333,163.81667 -77.33333,163.86667 -77.33333,163.91667 -77.33333,163.91667 -77.369997,163.91667 -77.406664,163.91667 -77.443331,163.91667 -77.479998,163.91667 -77.516665,163.91667 -77.553332,163.91667 -77.589999,163.91667 -77.626666,163.91667 -77.663333,163.91667 -77.7,163.86667 -77.7,163.81667 -77.7,163.76667 -77.7,163.71667 -77.7,163.66667 -77.7,163.61667 -77.7,163.56667 -77.7,163.51667 -77.7,163.46667 -77.7,163.41667 -77.7,163.41667 -77.663333,163.41667 -77.626666,163.41667 -77.589999,163.41667 -77.553332,163.41667 -77.516665,163.41667 -77.479998,163.41667 -77.443331,163.41667 -77.406664,163.41667 -77.369997,163.41667 -77.33333))"] | ["POINT(163.66667 -77.516665)"] | false | false |
Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores
|
0739512 |
2009-01-01 | Walker, Sally |
Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores |
This project answers a simple question: why are there so few fossils in sediment cores from Antarctica's continental shelf? Antarctica's benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains
|
0739693 |
2009-01-01 | Ashworth, Allan; Lewis, Adam |
Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains |
This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia. In terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica's ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise. | ["POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))"] | ["POINT(161 -77.5)"] | false | false |
Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains
|
0817163 |
2009-01-01 | Gehrels, George; Reiners, Peter |
Collaborative Research: SGER: Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains |
This Small Grant for Exploratory Research investigates the origin and evolution of the Gamburtsev subglacial mountains (GSM). These mountains are considered the nucleation point for Antarctica's largest ice sheets; however, being of indeterminate age, they may postdate ice sheet formation. As well, their formation could reflect tectonic events during the breakup of Gondwana. The project studies GSM-derived detrital zircon and apatite crystals from Prydz Bay obtained by the Ocean Drilling Program. Analytical work includes triple-dating thermochronometry by U/Pb, fission track, and (U/Th)/He methods. The combined technique offers insight into both high and low temperature processes, and is potentially sensitive to both the orogenic events and the subsequent cooling and exhumation due to erosion. In terms of broader impacts, this project supports research for a postdoctoral fellow. | ["POLYGON((72 -66,72.3 -66,72.6 -66,72.9 -66,73.2 -66,73.5 -66,73.8 -66,74.1 -66,74.4 -66,74.7 -66,75 -66,75 -66.3,75 -66.6,75 -66.9,75 -67.2,75 -67.5,75 -67.8,75 -68.1,75 -68.4,75 -68.7,75 -69,74.7 -69,74.4 -69,74.1 -69,73.8 -69,73.5 -69,73.2 -69,72.9 -69,72.6 -69,72.3 -69,72 -69,72 -68.7,72 -68.4,72 -68.1,72 -67.8,72 -67.5,72 -67.2,72 -66.9,72 -66.6,72 -66.3,72 -66))"] | ["POINT(73.5 -67.5)"] | false | false |
Regional Paleogeographic Views of Earth History
|
None | 2003-11-06 | Blakey, Ronald C. | No project link provided | This presentation uses a series of paleogeographic and plate-tectonic reconstructions to show the broad patterns of Phanerozoic Earth history. Organization is by region and in geologic order from oldest to youngest for each region. The Time Slice link shows all maps and globes of all regions by geologic time (the Periods). Options available from the menu are: - Paleogeographic globes, http://jan.ucc.nau.edu/~rcb7/paleogeographic.html; - Tectonics, Sedimentation, Paleogeography of North Atlantic Region, http://jan.ucc.nau.edu/~rcb7/nat.html; - Tectonics and Paleogeography of Mediterranean Region, http://jan.ucc.nau.edu/~rcb7/paleogeographic_alps.html; - Tectonics and Paleogeography of Central and Southern Asia, http://jan.ucc.nau.edu/~rcb7/paleogeographic_asia.html; and - Time Slice, http://jan.ucc.nau.edu/~rcb7/global_history.html, all maps and globes of all regions by geologic time, and a brief narrative for each time interval. | [] | [] | false | false |