{"dp_type": "Dataset", "free_text": "Subglacial"}
[{"awards": "2324092 MacKie, Emma", "bounds_geometry": ["POLYGON((95 -65,96 -65,97 -65,98 -65,99 -65,100 -65,101 -65,102 -65,103 -65,104 -65,105 -65,105 -65.7,105 -66.4,105 -67.1,105 -67.8,105 -68.5,105 -69.2,105 -69.9,105 -70.6,105 -71.3,105 -72,104 -72,103 -72,102 -72,101 -72,100 -72,99 -72,98 -72,97 -72,96 -72,95 -72,95 -71.3,95 -70.6,95 -69.9,95 -69.2,95 -68.5,95 -67.8,95 -67.1,95 -66.4,95 -65.7,95 -65))"], "date_created": "Mon, 21 Apr 2025 00:00:00 GMT", "description": "This dataset is a result of a study which uses Monte Carlo Markov Chain and geostatistics to infer subglacial topography from sparse bed elevation measurements. The dataset consists of 40 equally probable realizations of subglacial topography in the Denman region. Each of the realizations is constrained by conservation of ice mass (mass conservation), complies with bed elevation measurements from bedmap3 dataset, and has a realistic topographic roughness. The topography has 1 kilometer times 1 kilometer resolution on a regular grid in polar stereographic projection (EPSG 3412).", "east": 105.0, "geometry": ["POINT(100 -68.5)"], "keywords": "Antarctica; Cryosphere; Denman Glacier; East Antarctica; Geostatistics; Ice Thickness; MCMC; Model Data; Monte Carlo Markov Chain; Subglacial Topography", "locations": "Antarctica; East Antarctica; Denman Glacier", "north": -65.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Shao, Niya; MacKie, Emma; Michael, Field; McCormack, Felicity", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -72.0, "title": "Ensemble of subglacial topography beneath Denman Glacier generated by geostatistical Monte Carlo Markov Chain under mass conservation principle", "uid": "601927", "west": 95.0}, {"awards": "2423761 Blackburn, Terrence; 2042495 Blackburn, Terrence", "bounds_geometry": ["POLYGON((-180 -75,-144 -75,-108 -75,-72 -75,-36 -75,0 -75,36 -75,72 -75,108 -75,144 -75,180 -75,180 -76.5,180 -78,180 -79.5,180 -81,180 -82.5,180 -84,180 -85.5,180 -87,180 -88.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -88.5,-180 -87,-180 -85.5,-180 -84,-180 -82.5,-180 -81,-180 -79.5,-180 -78,-180 -76.5,-180 -75))"], "date_created": "Mon, 17 Mar 2025 00:00:00 GMT", "description": "This dataset includes geochemical analyses of carbonate nodules collected at Elephant Moraine and the Pensacola Mountains, East Antarctica. Oxygen and uranium-series isotope analyses indicate that these carbonates precipitated from glacial meltwater during deglacial periods in the late Pleistocene. Carbonate \u03b413C values as low as -32.75 \u2030 identify thermogenic methane as a primary carbon source, while clumped isotope measurements indicate formation temperatures of 12 - 20\u02daC, consistent with a geothermal origin. Lipid biomarker analyses further show that organic matter preserved in the nodules is highly thermally matured. These findings indicate that deep-sourced thermogenic methane migrated as hydrocarbon seeps to shallow pore spaces within basal sediments, demonstrating that geothermally active areas can be hotspots for methane accumulation below the Antarctic Ice Sheet. This material is based on services provided by the Polar Rock Repository with support from the National Science Foundation, under Cooperative Agreement OPP-2137467.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Subglacial", "locations": "Antarctica; Elephant Moraine; East Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Piccione, Gavin", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates; EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica", "projects": [{"proj_uid": "p0010459", "repository": "USAP-DC", "title": "EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica"}, {"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "uid": "601918", "west": -180.0}, {"awards": "2042495 Blackburn, Terrence", "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, 05 Mar 2025 00:00:00 GMT", "description": "This dataset contains U-series, d18O, d13C and 87Sr/86Sr data from 25 subglacial calcite precipitates from locations around the Antarctic ice sheet, primarily outlet glaciers near the ice sheet margins and nunataks in the Transantarctic mountains. Lat-lon data for each sample is given as well.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cryosphere", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Gagliardi, Jessica", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ", "uid": "601911", "west": -180.0}, {"awards": "1738989 Venturelli, Ryan", "bounds_geometry": ["POLYGON((-110.9665 -75.1967,-110.92041 -75.1967,-110.87432 -75.1967,-110.82822999999999 -75.1967,-110.78214 -75.1967,-110.73605 -75.1967,-110.68996 -75.1967,-110.64386999999999 -75.1967,-110.59778 -75.1967,-110.55169000000001 -75.1967,-110.5056 -75.1967,-110.5056 -75.20331,-110.5056 -75.20992000000001,-110.5056 -75.21653,-110.5056 -75.22314,-110.5056 -75.22975,-110.5056 -75.23636,-110.5056 -75.24297,-110.5056 -75.24958,-110.5056 -75.25619,-110.5056 -75.2628,-110.55169000000001 -75.2628,-110.59778 -75.2628,-110.64386999999999 -75.2628,-110.68996 -75.2628,-110.73605 -75.2628,-110.78214 -75.2628,-110.82822999999999 -75.2628,-110.87432 -75.2628,-110.92041 -75.2628,-110.9665 -75.2628,-110.9665 -75.25619,-110.9665 -75.24958,-110.9665 -75.24297,-110.9665 -75.23636,-110.9665 -75.22975,-110.9665 -75.22314,-110.9665 -75.21653,-110.9665 -75.20992000000001,-110.9665 -75.20331,-110.9665 -75.1967))"], "date_created": "Wed, 13 Nov 2024 00:00:00 GMT", "description": "Contains ice-penetrating radar data (10, 100, and 400 MHz) from the north side of the Mt. Murphy massif. Most of these data are closely spaced lines used for reconnaissance and site selection for a subglacial bedrock recovery drilling project very close to the ice margin at the north ridge of Kay Peak, a sub-peak of the massif. In addition, there are several longer exploratory lines that cross the embayment between the massif and the Crosson Ice Shelf, some of which may cross grounding lines. ", "east": -110.5056, "geometry": ["POINT(-110.73605 -75.22975)"], "keywords": "Antarctica; Cryosphere; Mount Murphy", "locations": "Antarctica; Mount Murphy", "north": -75.1967, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Balco, Greg; Campbell, Seth; Goehring, Brent", "project_titles": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "projects": [{"proj_uid": "p0010165", "repository": "USAP-DC", "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.2628, "title": "Ice-penetrating radar data from the northern embayment of the Mt. Murphy massif", "uid": "601834", "west": -110.9665}, {"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": "Antarctica; Antarctica; Totten Glacier", "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": "2317097 Venturelli, Ryan", "bounds_geometry": ["POLYGON((-99.793 -74.857,-99.7882 -74.857,-99.7834 -74.857,-99.77860000000001 -74.857,-99.77380000000001 -74.857,-99.769 -74.857,-99.7642 -74.857,-99.7594 -74.857,-99.75460000000001 -74.857,-99.74980000000001 -74.857,-99.745 -74.857,-99.745 -74.8583,-99.745 -74.8596,-99.745 -74.8609,-99.745 -74.8622,-99.745 -74.8635,-99.745 -74.8648,-99.745 -74.8661,-99.745 -74.8674,-99.745 -74.8687,-99.745 -74.87,-99.74980000000001 -74.87,-99.75460000000001 -74.87,-99.7594 -74.87,-99.7642 -74.87,-99.769 -74.87,-99.77380000000001 -74.87,-99.77860000000001 -74.87,-99.7834 -74.87,-99.7882 -74.87,-99.793 -74.87,-99.793 -74.8687,-99.793 -74.8674,-99.793 -74.8661,-99.793 -74.8648,-99.793 -74.8635,-99.793 -74.8622,-99.793 -74.8609,-99.793 -74.8596,-99.793 -74.8583,-99.793 -74.857))"], "date_created": "Wed, 02 Oct 2024 00:00:00 GMT", "description": "This data set contains an ice and firn density profile from Winkie Nunatak, West Antarctica. These data were collected when drilling a sub-ice access hole with an Eclipse drill in preparation for Winkie drill collection of subglacial bedrock. ", "east": -99.745, "geometry": ["POINT(-99.769 -74.8635)"], "keywords": "Antarctica; Cryosphere; Density; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Density; Ice Core Records; Snow/ice; Snow/Ice", "locations": "Antarctica", "north": -74.857, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Venturelli, Ryan", "project_titles": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "projects": [{"proj_uid": "p0010165", "repository": "USAP-DC", "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -74.87, "title": "Firn and Ice Density at Winkie Nunatak", "uid": "601838", "west": -99.793}, {"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": "Amundsen Sea; Antarctica; Amundsen Sea; Marie Byrd Land", "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": "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 Valley; Taylor Glacier; Antarctica", "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": "p0010243", "repository": "USAP-DC", "title": "U-Series Comminution Age Constraints on Taylor Valley Erosion"}, {"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "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": "1914698 Hansen, Samantha", "bounds_geometry": ["POLYGON((148 -71.5,150.4 -71.5,152.8 -71.5,155.2 -71.5,157.6 -71.5,160 -71.5,162.4 -71.5,164.8 -71.5,167.2 -71.5,169.6 -71.5,172 -71.5,172 -72.15,172 -72.8,172 -73.45,172 -74.1,172 -74.75,172 -75.4,172 -76.05,172 -76.7,172 -77.35,172 -78,169.6 -78,167.2 -78,164.8 -78,162.4 -78,160 -78,157.6 -78,155.2 -78,152.8 -78,150.4 -78,148 -78,148 -77.35,148 -76.7,148 -76.05,148 -75.4,148 -74.75,148 -74.1,148 -73.45,148 -72.8,148 -72.15,148 -71.5))"], "date_created": "Wed, 24 Jan 2024 00:00:00 GMT", "description": "As seismic data availability increases, the necessity for automated processing techniques has become increasingly evident. Expanded geophysical datasets collected over the past several decades across Antarctica provide excellent resources to evaluate different event detection approaches. We have used the traditional Short-Term Average/Long-Term Average (STA/LTA) algorithm to catalogue seismic data recorded by 19 stations in East Antarctica between 2012 and 2015. However, the complexities of the East Antarctic dataset, including low magnitude events and phenomena such as icequakes, warrant more advanced automated detection techniques. Therefore, we have also applied template matching as well as several deep learning algorithms, including Generalized Phase Detection (GPD), PhaseNet, BasicPhaseAE, and EQTransformer (EQT), to identify seismic phases within our dataset. Our goal was not only to increase the volume of detectable seismic events but also to gain insights into the effectiveness of these different automated approaches. Our assessment evaluated the completeness of the newly generated catalogs, the precision of identified event locations, and the quality of the picks. The final events corresponding to each of our three catalogs (based on STA/LTA, template matching, and machine learning, respectively) are listed in the provided files.", "east": 172.0, "geometry": ["POINT(160 -74.75)"], "keywords": "Antarctica; Geoscientificinformation; Machine Learning; Seismic Event Detection; Seismology; Seismometer", "locations": "Antarctica", "north": -71.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha; Ho, Long; Walter, Jacob", "project_titles": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)", "projects": [{"proj_uid": "p0010204", "repository": "USAP-DC", "title": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "East Antarctic Seismicity from different Automated Event Detection Algorithms", "uid": "601762", "west": 148.0}, {"awards": "1914698 Hansen, Samantha", "bounds_geometry": ["POLYGON((90 -65,99 -65,108 -65,117 -65,126 -65,135 -65,144 -65,153 -65,162 -65,171 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,171 -90,162 -90,153 -90,144 -90,135 -90,126 -90,117 -90,108 -90,99 -90,90 -90,90 -87.5,90 -85,90 -82.5,90 -80,90 -77.5,90 -75,90 -72.5,90 -70,90 -67.5,90 -65))"], "date_created": "Wed, 24 Jan 2024 00:00:00 GMT", "description": "Recent investigations in polar environments have examined solid-Earth-ice-sheet feedbacks and have emphasized that glacial isostatic adjustment, tectonic, and geothermal forcings exert first-order control on the physical conditions at and below the ice-bed interface and must be taken into account when evaluating ice-sheet evolution. However, the solid-Earth structure beneath much of Antarctica is still poorly constrained given the sparse distribution of seismic stations across the continent and the generally low seismicity rate. One region of particular interest is the Wilkes Subglacial Basin (WSB) in East Antarctica. During the mid-Pliocene warm period, the WSB may have contributed 3-4 m to the estimated 20 m rise in sea-level, indicating that this region could also play an important role in future warming scenarios. However, the WSB may have experienced notable bedrock uplift since the Pliocene; therefore, past geologic inferences of instability may not serve as a simple analogue for the future.\r\n\r\nUsing records of ambient seismic noise recorded by both temporary and long-term seismic networks, along with a full-waveform tomographic inversion technique, we have developed improved images of the lithospheric structure beneath East Antarctica, including the WSB. Empirical Green\u2019s Functions with periods between 40 and 340 s have been extracted using a frequency-time normalization technique, and a finite-difference approach with a spherical grid has been employed to numerically model synthetic seismograms. Associated sensitivity kernels have also been constructed using a scattering integral method. Our results suggest the WSB is underlain by slow seismic velocities, with faster seismic structure beneath the adjacent Transantarctic Mountains and the Belgica Subglacial Highlands. This may indicate that the WSB is associated with a region of thinner lithosphere, possibly associated with prior continental rifting. The seismic heterogeneity highlighted in our model could have significant implications for understanding the geodynamic origin of WSB topography and its influence on ice-sheet behavior.\r\n\r\nThe model file and associated plotting scripts are provided.", "east": 180.0, "geometry": ["POINT(135 -77.5)"], "keywords": "Ambient Noise; Antarctica; East Antarctica; Geoscientificinformation; Seismic Tomography; Seismology", "locations": "Antarctica; East Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha; Emry, Erica", "project_titles": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)", "projects": [{"proj_uid": "p0010204", "repository": "USAP-DC", "title": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Full Waveform Ambient Noise Tomography for East Antarctica", "uid": "601763", "west": 90.0}, {"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": "1738989 Venturelli, Ryan", "bounds_geometry": ["POINT(-110.96038 -75.21526)"], "date_created": "Mon, 10 Jul 2023 00:00:00 GMT", "description": "Included in this dataset are in situ carbon-14 concentrations for a series of bedrock cores recovered from the subglacial extension of Kay Peak, a grounding-line-proximal ridge of the volcanic edifice Mount Murphy (near Thwaites and Pope glaciers). Concentrations measured in these bedrock samples have been used in the associated publication to demonstrate that the Thwaites-Pope glacier system was thinner in the Holocene than it is today. ", "east": -110.96038, "geometry": ["POINT(-110.96038 -75.21526)"], "keywords": "Antarctica; Cosmogenic Radionuclides; Mount Murphy; Subglacial Bedrock", "locations": "Mount Murphy; Antarctica", "north": -75.21526, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Venturelli, Ryan; Goehring, Brent; Balco, Gregory", "project_titles": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "projects": [{"proj_uid": "p0010165", "repository": "USAP-DC", "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.21526, "title": "In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers", "uid": "601705", "west": -110.96038}, {"awards": "2317097 Venturelli, Ryan", "bounds_geometry": ["POLYGON((-99.793 -74.857,-99.7882 -74.857,-99.7834 -74.857,-99.77860000000001 -74.857,-99.77380000000001 -74.857,-99.769 -74.857,-99.7642 -74.857,-99.7594 -74.857,-99.75460000000001 -74.857,-99.74980000000001 -74.857,-99.745 -74.857,-99.745 -74.8583,-99.745 -74.8596,-99.745 -74.8609,-99.745 -74.8622,-99.745 -74.8635,-99.745 -74.8648,-99.745 -74.8661,-99.745 -74.8674,-99.745 -74.8687,-99.745 -74.87,-99.74980000000001 -74.87,-99.75460000000001 -74.87,-99.7594 -74.87,-99.7642 -74.87,-99.769 -74.87,-99.77380000000001 -74.87,-99.77860000000001 -74.87,-99.7834 -74.87,-99.7882 -74.87,-99.793 -74.87,-99.793 -74.8687,-99.793 -74.8674,-99.793 -74.8661,-99.793 -74.8648,-99.793 -74.8635,-99.793 -74.8622,-99.793 -74.8609,-99.793 -74.8596,-99.793 -74.8583,-99.793 -74.857))"], "date_created": "Fri, 24 Mar 2023 00:00:00 GMT", "description": "This data set contains unprocessed radar profiles collected with a GSSI 200 MHz Hyperstacking antenna near Winkie Nunatak, West Antarctica. This data was collected to estimate depth-to-bedrock along a subglacial ridge line at depths between 20 - 120 meters. ", "east": -99.745, "geometry": ["POINT(-99.769 -74.8635)"], "keywords": "Antarctica; Ice Penetrating Radar; Pine Island Glacier; Subglacial Bedrock", "locations": "Pine Island Glacier; Antarctica", "north": -74.857, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Braddock, Scott", "project_titles": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "projects": [{"proj_uid": "p0010165", "repository": "USAP-DC", "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -74.87, "title": "200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica", "uid": "601677", "west": -99.793}, {"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": "Antarctica; Mercer Subglacial Lake", "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": "Antarctica; Mercer Subglacial Lake; Mercer Subglacial Lake; West Antarctic Ice Sheet", "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 water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (\u03b42H and \u03b418O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "locations": "Mercer Subglacial Lake; Antarctica; West Antarctic Ice Sheet; Mercer Subglacial Lake", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; 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": "Water column biogeochemical data from Mercer Subglacial Lake", "uid": "601663", "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": "West Antarctic Ice Sheet; Antarctica; Mercer Subglacial Lake; 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": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Tue, 17 Jan 2023 00:00:00 GMT", "description": "This dataset includes binned conductivity, temperature and pressure measurements from Mercer Subglacial Lake and the borehole drilled to access the lake by the SALSA project, as well as additional physical parameters derived from these measurements using the TEOS-10 equation of state.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Conductivity; CTD; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; Physical Properties; SALSA; Subglacial Lake; Temperature", "locations": "Antarctica; Mercer Subglacial Lake", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Priscu, John; Leventer, Amy; 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": "CTD data from Mercer Subglacial Lake and access borehole", "uid": "601657", "west": -149.50134}, {"awards": "2042495 Blackburn, Terrence", "bounds_geometry": null, "date_created": "Wed, 10 Aug 2022 00:00:00 GMT", "description": "This file includes U-series isotopic and 234U/230Th chronologic data from two chemical precipitates deposited beneath the Antarctic Ice Sheet. Precipitate mineral compositions consist of opal and calcite layers. Sample MA113 was found at Mount Achernar moraine (84.2\u00b0S, 161\u00b0E), and sample PRR50489 was found at Elephant Moraine (76.3\u00b0S, 157.3\u00b0E).", "east": null, "geometry": null, "keywords": "Antarctica; East Antarctica", "locations": "Antarctica; East Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Piccione, Gavin; Blackburn, Terrence", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Subglacial Precipitates Record Antarctic Ice Sheet Response to Pleistocene Millennial Climate Cycles", "uid": "601594", "west": null}, {"awards": "9319379 Blankenship, Donald", "bounds_geometry": ["POLYGON((-180 -75,-172 -75,-164 -75,-156 -75,-148 -75,-140 -75,-132 -75,-124 -75,-116 -75,-108 -75,-100 -75,-100 -76.5,-100 -78,-100 -79.5,-100 -81,-100 -82.5,-100 -84,-100 -85.5,-100 -87,-100 -88.5,-100 -90,-108 -90,-116 -90,-124 -90,-132 -90,-140 -90,-148 -90,-156 -90,-164 -90,-172 -90,180 -90,172 -90,164 -90,156 -90,148 -90,140 -90,132 -90,124 -90,116 -90,108 -90,100 -90,100 -88.5,100 -87,100 -85.5,100 -84,100 -82.5,100 -81,100 -79.5,100 -78,100 -76.5,100 -75,108 -75,116 -75,124 -75,132 -75,140 -75,148 -75,156 -75,164 -75,172 -75,-180 -75))"], "date_created": "Sun, 24 Jul 2022 00:00:00 GMT", "description": "These data represent the 1-km decimated version of the SOAR ice thickness data provided to the Bedmap2 project, collected as part of various projects between 1991 and 2001. It encompasses the Corridor Aerogeophysics of the South East Ross Zone (CASERTZ) surveys of the Byrd Subglacial Basin (BSB), Bindschadler Ice Stream (WAZ/TKD), and the upstream catchments of Kamb Ice Steam and Willians Ice Stream (IRE); targeted West Antarctic glaciology projects (IPB/WAZ/DVD/STI/LIV); corridors across the Transantarctic Mountains to South Pole (PPT) and Dome C (WLK); and a version of the Lake Vostok dataset (LVS). Data were collected as stacked log detected traces by the SOAR TUD IV system with an attached digitizer. The digitizer was significantly updated in 1997 (RTZ6). Data interpretation approaches can be found in Blankenship et al., 2001.\r\n\r\nData is in ASCII format. Transects are separated by GMT style segment headers with the transect name.\r\nColumns are:\r\n1. Year\r\n2. Day of Year\r\n3. Seconds of Day\r\n4. Longitude (degrees, WGS-84)\r\n5. Latitude (degrees, WGS-84)\r\n6. Easting (meters, EPSG 3031; Polar Stereographic with true scale at 71\u02daS)\r\n7. Northing (meters, EPSG 3031; Polar Stereographic with true scale at 71\u02daS)\r\n8. Surface Elevation (meters, WGS-84) - derived where possible from laser data\r\n9. Ice thickness (meters, using a speed of light in air of 299705000 m/s and a refractive index of 1.78; no firn correction)\r\n10. Bed Elevation (meters, WGS-84) - column 8 minus column 9\r\n11. The transect name formatted by Project/Set/Transect\r\n", "east": 100.0, "geometry": ["POINT(-180 -82.5)"], "keywords": "Antarctica; Ice Penetrating Radar; Ice Thickness; SOAR", "locations": "Antarctica; Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Blankenship, Donald D.; Young, Duncan A.; Kempf, Scott D.", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Support Office for Airborne Research 1 km sampled ice thickness data", "uid": "601588", "west": -100.0}, {"awards": "1643917 Fricker, Helen", "bounds_geometry": ["POLYGON((-163.646 -84.186,-162.58715 -84.186,-161.5283 -84.186,-160.46945 -84.186,-159.4106 -84.186,-158.35175 -84.186,-157.2929 -84.186,-156.23405 -84.186,-155.1752 -84.186,-154.11635 -84.186,-153.0575 -84.186,-153.0575 -84.20871,-153.0575 -84.23142,-153.0575 -84.25413,-153.0575 -84.27684,-153.0575 -84.29955,-153.0575 -84.32226,-153.0575 -84.34497,-153.0575 -84.36768,-153.0575 -84.39039,-153.0575 -84.4131,-154.11635 -84.4131,-155.1752 -84.4131,-156.23405 -84.4131,-157.2929 -84.4131,-158.35175 -84.4131,-159.4106 -84.4131,-160.46945 -84.4131,-161.5283 -84.4131,-162.58715 -84.4131,-163.646 -84.4131,-163.646 -84.39039,-163.646 -84.36768,-163.646 -84.34497,-163.646 -84.32226,-163.646 -84.29955,-163.646 -84.27684,-163.646 -84.25413,-163.646 -84.23142,-163.646 -84.20871,-163.646 -84.186))"], "date_created": "Fri, 25 Feb 2022 00:00:00 GMT", "description": "This archive contains magnetotelluric (MT) responses estimated from MT time series data that were collected to study subglacial groundwater beneath Whillans Ice Stream, West Antarctica. Data acquisition took place during the 2018/2019 Antarctic summer field season. 27 MT stations were collected at Whillans Subglacial Lake (SLW) and 16 stations were obtained at its hypothesized downstream outlet to the ocean, Whillans Grounding Zone (WGZ). The MT responses are provided as text files in the .zmm format output by the MT data processing code, but have also been converted to the more widely used .edi text file format for convenience. All sensor orientations are listed as geomagnetic azimuths, which for this region are substantially different than the corresponding geographic azimuths.", "east": -153.0575, "geometry": ["POINT(-158.35175 -84.29955)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Stream; Magnetotelluric; Subglacial; Whillans Ice Stream", "locations": "Whillans Ice Stream; Antarctica", "north": -84.186, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Gustafson, Chloe; Key, Kerry; Siegfried, Matthew; Fricker, Helen", "project_titles": "Mapping Antarctic Subglacial Water with Novel Electromagnetic Techniques", "projects": [{"proj_uid": "p0010300", "repository": "USAP-DC", "title": "Mapping Antarctic Subglacial Water with Novel Electromagnetic Techniques"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.4131, "title": "Wideband magnetotelluric responses from Whillans Ice Stream, West Antarctica", "uid": "601526", "west": -163.646}, {"awards": "1643353 Christianson, Knut; 1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"], "date_created": "Thu, 06 Jan 2022 00:00:00 GMT", "description": "These are ground-based radar data collected from a subglacial lake ~15 km from the geographic South Pole. Data were collected with the Autonomous phase-sensitive Radio Echo Sounder (ApRES) (Nicholls et al., 2015). The intention of this dataset is to be used for vertical velocity structure and interpretation.", "east": 179.999976057, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Apres; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; South Pole; Subglacial Lakes; Vertical Velocity", "locations": "South Pole; South Pole; Antarctica", "north": -89.752739299, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Hills, Benjamin", "project_titles": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow", "projects": [{"proj_uid": "p0010160", "repository": "USAP-DC", "title": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -89.998090011, "title": "South Pole Lake ApRES Radar", "uid": "601503", "west": -179.9989061}, {"awards": "1744649 Christianson, Knut; 1643353 Christianson, Knut", "bounds_geometry": ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"], "date_created": "Thu, 06 Jan 2022 00:00:00 GMT", "description": "These are ground-based GNSS data collected from a subglacial lake ~15 km from the geographic South Pole.\r\nData were collected with two separate antenna/receiver systems: 1) Septentrio Altus APS3G antenna/receiver 2) Trimble NetR8 and Trimble Zephyr Geodetic antenna.", "east": 179.999976057, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GNSS; GPS; GPS Data; South Pole; Subglacial Lakes", "locations": "South Pole; Antarctica; South Pole", "north": -89.752739299, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Hills, Benjamin", "project_titles": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow", "projects": [{"proj_uid": "p0010160", "repository": "USAP-DC", "title": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -89.998090011, "title": "South Pole Lake GNSS", "uid": "601502", "west": -179.9989061}, {"awards": "1543453 Lyons, W. Berry", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Thu, 23 Dec 2021 00:00:00 GMT", "description": "This dataset includes the following measurements from Niskin casts at Mercer Subglacial Lake as part of the SALSA project: noble gases and their isotopes, d13C-DIC, Ge, 87Sr/86Sr, and 234U/238U", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Mercer Subglacial Lake; Noble Gas", "locations": "Mercer Subglacial Lake; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Gardner, Christopher B.; Lyons, W. Berry", "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 (SLM) noble gas and isotopic data", "uid": "601498", "west": -149.50134}, {"awards": "1246353 Anderson, John; 1745055 Stearns, Leigh; 1745043 Simkins, Lauren", "bounds_geometry": ["POLYGON((174 -75,174.4 -75,174.8 -75,175.2 -75,175.6 -75,176 -75,176.4 -75,176.8 -75,177.2 -75,177.6 -75,178 -75,178 -75.2,178 -75.4,178 -75.6,178 -75.8,178 -76,178 -76.2,178 -76.4,178 -76.6,178 -76.8,178 -77,177.6 -77,177.2 -77,176.8 -77,176.4 -77,176 -77,175.6 -77,175.2 -77,174.8 -77,174.4 -77,174 -77,174 -76.8,174 -76.6,174 -76.4,174 -76.2,174 -76,174 -75.8,174 -75.6,174 -75.4,174 -75.2,174 -75))"], "date_created": "Mon, 04 Oct 2021 00:00:00 GMT", "description": "Bathymetry from multibeam echo sounding data in Pennell Trough, Ross Sea, Antarctica was collected onboard the RVIB Nathaniel B. Palmer (NBP) 15-02 cruise using a Kongsberg EM122 operating in dual swath mode at 12 kHz frequency with a 1\u00b0\u00d71\u00b0 beam width, swath angular coverage set to 62\u00b0\u00d762\u00b0, and 30-60% overlap between survey lines. All raw, ping-edited geophysical data collected on NBP15-02 can be accessed using the Marine Geoscience Data System (Cruise DOI: 10.7284/901477). The bathymetry dataset here is gridded at 20-m resolution with a water depth-dependent vertical resolution on the order of decimeters. Two shapefiles are provided for ice-marginal landforms and meltwater landforms observable in the bathymetry data. The purpose of collecting the bathymetry data on cruise NBP15-02 was to better understand the glacial history of the Ross Sea, and the dataset, inclusive of bathymetry data and shapefiles of glacial landforms, from Pennell Trough are used to understand impacts on subglacial channel morphology and organization during the deglaciation of the region following the Last Glacial Maximum. The published dataset was used and analyzed in the article \"Topographic controls on channelized meltwater in the subglacial environment\" by Simkins, L.M., Greenwood, S.L., Munevar Garcia, S., Eareckson, E.A., Anderson, J.B., and Prothro, L.O, which was published in Geophysical Research Letters in 2021 (DOI: 10.1029/2021GL094678).", "east": 178.0, "geometry": ["POINT(176 -76)"], "keywords": "Antarctica; Bathymetry; Elevation; Geomorphology; Glacial History; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; NBP1502; Pennell Trough; Ross Sea; R/v Nathaniel B. Palmer", "locations": "Ross Sea; Pennell Trough; Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Greenwood, Sarah; Munevar Garcia, Santiago; Eareckson, Elizabeth; Anderson, John; Prothro, Lindsay; Simkins, Lauren", "project_titles": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations; Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum.", "projects": [{"proj_uid": "p0010269", "repository": "USAP-DC", "title": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations"}, {"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": -77.0, "title": "Pennell Trough, Ross Sea bathymetry and glacial landforms", "uid": "601474", "west": 174.0}, {"awards": "1543441 Fricker, Helen; 1656518 Gumport, Patricia", "bounds_geometry": null, "date_created": "Tue, 14 Sep 2021 00:00:00 GMT", "description": "This dataset includes raw, uncalibrated voltage vs time measurements from a bistatic radar receiver. We also include some processed data including upsampled matched filtered data, GPS receiver position, antenna separation", "east": null, "geometry": null, "keywords": "Antarctica; Bistatic Radar; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "locations": "Greenland; Lake Whillans; Antarctica; Whillans Ice Stream; Store Glacier", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "persons": "Bienert, Nicole; Schroeder, Dustin; Siegfried, Matthew; Peters, Sean; MacKie, Emma; Dawson, Eliza; Christoffersen, Poul", "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": null, "title": "Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland", "uid": "601472", "west": null}, {"awards": null, "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, 13 Aug 2021 00:00:00 GMT", "description": "This data set contains (1) ice thickness (H) and basal sliding coefficient (beta) maps for the Antarctic Ice Sheet from Arthern et al. (2015) \"Flow speed within the Antarctic ice sheet and its controls inferred from satellite observations\", and (2) Antarctic subglacial lake locations and estimated sizes from Siegfried and Fricker (2018) \"Thirteen years of subglacial lake activity in Antarctica from multi-mission satellite altimetry\". Data are in zarr (thickness and sliding coefficient maps) and ASCII (lake locations and sizes) formats.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Antarctic Ice Sheet; Ice Thickness; Subglacial Lake", "locations": "Antarctica; Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": null, "persons": "Stubblefield, Aaron; Kingslake, Jonathan; Siegfried, Matthew; Arthern, Robert", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Antarctic Ice Thickness, Slipperiness, and Subglacial Lake Locations", "uid": "601470", "west": -180.0}, {"awards": "1443690 Young, Duncan", "bounds_geometry": ["POLYGON((118 -74.1,118.9 -74.1,119.8 -74.1,120.7 -74.1,121.6 -74.1,122.5 -74.1,123.4 -74.1,124.3 -74.1,125.2 -74.1,126.1 -74.1,127 -74.1,127 -74.33,127 -74.56,127 -74.79,127 -75.02,127 -75.25,127 -75.48,127 -75.71,127 -75.94,127 -76.17,127 -76.4,126.1 -76.4,125.2 -76.4,124.3 -76.4,123.4 -76.4,122.5 -76.4,121.6 -76.4,120.7 -76.4,119.8 -76.4,118.9 -76.4,118 -76.4,118 -76.17,118 -75.94,118 -75.71,118 -75.48,118 -75.25,118 -75.02,118 -74.79,118 -74.56,118 -74.33,118 -74.1))"], "date_created": "Wed, 14 Jul 2021 00:00:00 GMT", "description": "This data set includes compiled and gridded ice thickness, bed elevation, and bed roughness originally published in Young et al., 2017, as well as subglacial lakes identified at the Little Dome C old ice candidate site in Antarctica.", "east": 127.0, "geometry": ["POINT(122.5 -75.25)"], "keywords": "Antarctica; Epica Dome C; ICECAP; Ice Penetrating Radar; Subglacial Lake", "locations": "Antarctica; Epica Dome C; Antarctica", "north": -74.1, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Young, Duncan A.; Roberts, Jason; Ritz, Catherine; Frezzotti, Massimo; Quartini, Enrica; Cavitte, Marie G. P; Tozer, Carly; Steinhage, Daniel; Urbini, Stefano; Corr, Hugh F. J.; Van Ommen, Tas; Blankenship, Donald D.", "project_titles": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)", "projects": [{"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Dome C Ice Core", "south": -76.4, "title": "ICECAP: Gridded boundary conditions for Little Dome C, Antarctica, and extracted subglacial lake locations", "uid": "601463", "west": 118.0}, {"awards": "0636719 Joughin, Ian; 0636970 Tulaczyk, Slawek", "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, 21 Apr 2021 00:00:00 GMT", "description": "This data set contains lake boundaries, volume changes, and gridded elevations for 124 active subglacial lakes beneath the Antarctic ice sheet. Lakes were identified using laser altimetry data obtained from 2003 to 2009 by NASA\u0027s Ice, Cloud, and Land Elevation Satellite (ICESat) mission. The data are provided in Keyhole Markup Language (KML), comma-separated values (CSV), and GEOTiff formats.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Altimetry; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Icesat; Laser Altimetry; Subglacial Lake", "locations": "Antarctica; Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Smith, Ben; Joughin, Ian; Tulaczyk, Slawek; Fricker, Helen", "project_titles": "Collaborative Research: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries", "projects": [{"proj_uid": "p0000115", "repository": "USAP-DC", "title": "Collaborative Research: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Antarctic Active Subglacial Lake Inventory from ICESat Altimetry", "uid": "601439", "west": -180.0}, {"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": "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": "Antarctica; Weddell Sea", "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": "1543452 Blankenship, Donald; 0733025 Blankenship, Donald; 1443690 Young, Duncan; 0636724 Blankenship, Donald", "bounds_geometry": ["POLYGON((80 -65,89 -65,98 -65,107 -65,116 -65,125 -65,134 -65,143 -65,152 -65,161 -65,170 -65,170 -66.5,170 -68,170 -69.5,170 -71,170 -72.5,170 -74,170 -75.5,170 -77,170 -78.5,170 -80,161 -80,152 -80,143 -80,134 -80,125 -80,116 -80,107 -80,98 -80,89 -80,80 -80,80 -78.5,80 -77,80 -75.5,80 -74,80 -72.5,80 -71,80 -69.5,80 -68,80 -66.5,80 -65))"], "date_created": "Mon, 24 Aug 2020 00:00:00 GMT", "description": "The International Collaborative Exploration of the Cryosphere though Airborne Profiling (ICECAP) collected five seasons of aerogeophysical data data through the NSFs International Polar Year and NASAs Operation Ice Bridge programs in East Antarctica, using the coherent HiCARS 60 MHz radar system. By comparing echo strengths for different focusing apertures, and accounting for the ranges and angles involved, we can derive the \"specularity content\" of the bed echo, a proxy for small scale bed roughness and a good indicator for subglacial water pressure in regions of distributed subglacial water (Schroeder et al., 2014, IEEE GRSL, 10.1109/LGRS.2014.2337878; IEEE; Dow et al., 2019, EPSL https://doi.org/10.1016/j.epsl.2019.115961). Specularity data are inherently noisy, so these products have been smoothed with a 1 km filter.", "east": 170.0, "geometry": ["POINT(125 -72.5)"], "keywords": "Antarctica; East Antarctica; ICECAP; Ice Penetrating Radar; Radar Echo Sounder; Radar Echo Sounding; Subglacial Hydrology", "locations": "East Antarctica; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Young, Duncan A.; Blankenship, Donald D.; Roberts, Jason; Siegert, Martin; van Ommen, Tas; Greenbaum, Jamin; Schroeder, Dustin", "project_titles": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP); Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System; East Antarctic Grounding Line Experiment (EAGLE); IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)", "projects": [{"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}, {"proj_uid": "p0000254", "repository": "USAP-DC", "title": "East Antarctic Grounding Line Experiment (EAGLE)"}, {"proj_uid": "p0000174", "repository": "USAP-DC", "title": "Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System"}, {"proj_uid": "p0000719", "repository": "USAP-DC", "title": "IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "ICECAP Basal Interface Specularity Content Profiles: IPY and OIB", "uid": "601371", "west": 80.0}, {"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": "1341658 Mukhopadhyay, Sujoy", "bounds_geometry": ["POLYGON((-116.46 -84.78,-116.452 -84.78,-116.444 -84.78,-116.436 -84.78,-116.428 -84.78,-116.42 -84.78,-116.412 -84.78,-116.404 -84.78,-116.396 -84.78,-116.388 -84.78,-116.38 -84.78,-116.38 -84.781,-116.38 -84.782,-116.38 -84.783,-116.38 -84.784,-116.38 -84.785,-116.38 -84.786,-116.38 -84.787,-116.38 -84.788,-116.38 -84.789,-116.38 -84.79,-116.388 -84.79,-116.396 -84.79,-116.404 -84.79,-116.412 -84.79,-116.42 -84.79,-116.428 -84.79,-116.436 -84.79,-116.444 -84.79,-116.452 -84.79,-116.46 -84.79,-116.46 -84.789,-116.46 -84.788,-116.46 -84.787,-116.46 -84.786,-116.46 -84.785,-116.46 -84.784,-116.46 -84.783,-116.46 -84.782,-116.46 -84.781,-116.46 -84.78))"], "date_created": "Sun, 28 Jun 2020 00:00:00 GMT", "description": "The data set consists of cosmogenic berrylium-10 and aluminum-26, along with neon-21, in a set of 4 rock-cores obtained from the Ohio Range, West Antarctica. The rock cores were obtained using the WInkie drill. The depth to the cores varies from 12 meters to 28 meters. The recovered rock cores analyzed for the cosmogenic isotopes varies from 22 cm long to 50 cm long. The data include the following formation: sample details, cosmogenic berrylium-10, aluminum-26 and upper bounds for cosmogenic 21 (since samples have nucleogenic 21) and the step heating data for neon. The data are in Mircrosoft excel format.", "east": -116.38, "geometry": ["POINT(-116.42 -84.785)"], "keywords": "Aluminum-26; Antarctica; Beryllium-10; Cosmogenic Dating; Cosmogenic Radionuclides; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Fluctuations; Ohio Range; Rocks", "locations": "Antarctica; Ohio Range", "north": -84.78, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Mukhopadhyay, Sujoy", "project_titles": "Constraining Plio-Pleistocene West Antarctic Ice Sheet Behavior from the Ohio Range and Scott Glacier", "projects": [{"proj_uid": "p0010113", "repository": "USAP-DC", "title": "Constraining Plio-Pleistocene West Antarctic Ice Sheet Behavior from the Ohio Range and Scott Glacier"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.79, "title": "Ohio Range Subglacial rock core cosmogenic nuclide data", "uid": "601351", "west": -116.46}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed IcePenetrating Radar Altimeter Shot Data (version 2) acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Navigation; Radar; SOAR; Subglacial Lakes", "locations": "Lake Vostok; Antarctica; East Antarctica", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey airborne radar data", "uid": "601300", "west": 101.5}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed IcePenetrating Radar Altimeter Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of ASCII format and include Ice LayerThickness data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "keywords": "Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Sheet; Ice Stratigraphy; Ice Thickness; Ice Thickness Distribution; Lake Vostok; Radar; Radar Altimetry; Radar Echo Sounder; SOAR; Subglacial Lake", "locations": "East Antarctica; Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey ice thickness data", "uid": "601297", "west": 101.5}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Aerogeophysics; AGAP; Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "East Antarctica; Antarctica; Gamburtsev Mountains", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Altimeter Shot Data (SEGY, version 1) from the Gamburtsev Mountains in Antarctica acquired during the GAMBIT Twin Otter expedition AGAP_GAMBIT (2008)", "uid": "601283", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are jpeg images of Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "AGAP; Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "Gamburtsev Mountains; Antarctica; East Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (jpeg images) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601286", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of MATLAB format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "East Antarctica; Gamburtsev Mountains; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (Matlab format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601284", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of Netcdf format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar Echo Sounder", "locations": "Gamburtsev Mountains; Antarctica; East Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (Netcdf format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601285", "west": 65.0}, {"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": "Fri, 17 Jan 2020 00:00:00 GMT", "description": "This data set includes counts of palynomorphs from subglacial and sub-ice shelf tills from beneath the West Antarctic Ice Sheet. In addition to counts the biostratigraphic ranges are presented on separate tabs. ", "east": -120.0, "geometry": ["POINT(-150 -82.5)"], "keywords": "Antarctica; Pollen; West Antarctica; WISSARD", "locations": "Antarctica; West Antarctica; West Antarctica", "north": -80.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Coenen, Jason; Baudoin, Patrick; Warny, Sophie; Askin, Rosemary; Scherer, Reed Paul; Casta\u00f1eda, Isla", "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: Palynomorph Data Set", "uid": "601245", "west": 180.0}, {"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": "1341728 Stone, John", "bounds_geometry": ["POLYGON((-86.3 -81,-86.17 -81,-86.04 -81,-85.91 -81,-85.78 -81,-85.65 -81,-85.52 -81,-85.39 -81,-85.26 -81,-85.13 -81,-85 -81,-85 -81.03,-85 -81.06,-85 -81.09,-85 -81.12,-85 -81.15,-85 -81.18,-85 -81.21,-85 -81.24,-85 -81.27,-85 -81.3,-85.13 -81.3,-85.26 -81.3,-85.39 -81.3,-85.52 -81.3,-85.65 -81.3,-85.78 -81.3,-85.91 -81.3,-86.04 -81.3,-86.17 -81.3,-86.3 -81.3,-86.3 -81.27,-86.3 -81.24,-86.3 -81.21,-86.3 -81.18,-86.3 -81.15,-86.3 -81.12,-86.3 -81.09,-86.3 -81.06,-86.3 -81.03,-86.3 -81))"], "date_created": "Wed, 09 Oct 2019 00:00:00 GMT", "description": "This data set contains measurements of cosmic-ray-produced Be-10 and Al-26 in quartz from the RB-2 core, recovered from bedrock at a depth of 150 m below the West Antarctic Ice Sheet surface in the Pirrit Hills. The core site is located at latitude S81.09948, longitude W85.15694. Core length is approximately 8 meters. Lithology is A-type granite, similar in composition to bedrock exposed on nearby Harter Nunatak and other mountains in the Pirrit Hills (Lee et al. Geosci. J. 16, 421-433). Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory. Chemical processing and purification methods are described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Aluminum isotope ratios were measured at PRIME Lab, Purdue University, relative to the KNSTD-Al-01-5-2 standard, assuming a standard Al-26/Al-27 ratio of 1.818E-12 (KNSTD normalization). Uncertainties are 1-sigma and include full AMS errors and all known sources of laboratory uncertainty.", "east": -85.0, "geometry": ["POINT(-85.65 -81.15)"], "keywords": "Aluminum-26; Antarctica; Be-10; Bedrock Core; Beryllium-10; Chemistry:rock; Chemistry:Rock; Cosmogenic; Cosmogenic Dating; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope Data; Pirrit Hills; Rocks; Solid Earth; Subglacial Bedrock", "locations": "Pirrit Hills; Antarctica", "north": -81.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Stone, John", "project_titles": "EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse", "projects": [{"proj_uid": "p0010057", "repository": "USAP-DC", "title": "EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.3, "title": "Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data", "uid": "601214", "west": -86.3}, {"awards": "1745137 Schroeder, Dustin", "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, 02 Oct 2019 00:00:00 GMT", "description": "These data accompany the paper \"Antarctic Topographic Realizations and Geostatistical Modeling Used to Map Subglacial Lakes\" (MacKie et al., in review). This dataset contains 100 geostatistically generated subglacial topographic realizations for Antarctica. Data science techniques were used to calculate the probability of the occurrence of radar-detected lakes and altimetry-detected (active) lakes across the continent, using each topographic realization as a parameter. This generated 100 probability maps of the likelihood of radar-detected lake occurrence and 100 probability maps of active lake occurrence. Further statistics were used to generate 100 binary maps showing expected radar-detected lake locations. The ensemble of realizations can be used for uncertainty quantification.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Active Lakes; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; Model Data; Snow/ice; Snow/Ice; Subglacial Lakes; Topography", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "MacKie, Emma; Schroeder, Dustin; Caers, Jef; Scheidt, Celine; Siegfried, Matthew", "project_titles": "CAREER: Cross-Instrument Synthesis of Antarctic Radar Sounding Observations", "projects": [{"proj_uid": "p0010058", "repository": "USAP-DC", "title": "CAREER: Cross-Instrument Synthesis of Antarctic Radar Sounding Observations"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Antarctic topographic and subglacial lake geostatistical simulations", "uid": "601213", "west": -180.0}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((150 -72,152 -72,154 -72,156 -72,158 -72,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,170 -72.3,170 -72.6,170 -72.9,170 -73.2,170 -73.5,170 -73.8,170 -74.1,170 -74.4,170 -74.7,170 -75,168 -75,166 -75,164 -75,162 -75,160 -75,158 -75,156 -75,154 -75,152 -75,150 -75,150 -74.7,150 -74.4,150 -74.1,150 -73.8,150 -73.5,150 -73.2,150 -72.9,150 -72.6,150 -72.3,150 -72))"], "date_created": "Wed, 31 Jul 2019 00:00:00 GMT", "description": "The Transantarctic Mountains (TAMs) are the largest non-collisional mountain range on Earth. Their origin, as well as the origin of the Wilkes Subglacial Basin (WSB) along the inland side of the TAMs, have been widely debated, and a key constraint to distinguish between competing models is the underlying crustal structure. Previous investigations have examined this structure but have primarily focused on a small region of the central TAMs near Ross Island, providing little along-strike constraint. In this study, we use data from the new Transantarctic Mountains Northern Network and from five stations operated by the Korea Polar Research Institute to investigate the crustal structure beneath a previously unexplored portion of the TAMs. Using S-wave receiver functions and Rayleigh wave phase velocities, crustal thickness and average crustal shear velocity (\uf8e5Vs) are resolved within \u00b14 km and \u00b10.1 km/s, respectively. The crust thickens from ~20 km near the Ross Sea coast to ~46 km beneath the northern TAMs, which is somewhat thicker than that imaged in previous studies beneath the central TAMs. The crust thins to ~41 km beneath the WSB.\uf8e5Vs ranges from ~3.1-3.9 km/s, with slower velocities near the coast. Our findings are consistent with a flexural origin for the TAMs and WSB, where these features result from broad flexure of the East Antarctic lithosphere and uplift along its western edge due to thermal conduction from hotter mantle beneath West Antarctica. Locally thicker crust may explain the ~1 km of additional topography in the northern TAMs compared to the central TAMs.", "east": 170.0, "geometry": ["POINT(160 -73.5)"], "keywords": "Antarctica; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -72.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha", "project_titles": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "projects": [{"proj_uid": "p0000300", "repository": "USAP-DC", "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins", "uid": "601194", "west": 150.0}, {"awards": "1144176 Lyons, W. Berry", "bounds_geometry": ["POLYGON((162.250099 -77.719928,162.2519358 -77.719928,162.2537726 -77.719928,162.2556094 -77.719928,162.2574462 -77.719928,162.259283 -77.719928,162.2611198 -77.719928,162.2629566 -77.719928,162.2647934 -77.719928,162.2666302 -77.719928,162.268467 -77.719928,162.268467 -77.7201251,162.268467 -77.7203222,162.268467 -77.7205193,162.268467 -77.7207164,162.268467 -77.7209135,162.268467 -77.7211106,162.268467 -77.7213077,162.268467 -77.7215048,162.268467 -77.7217019,162.268467 -77.721899,162.2666302 -77.721899,162.2647934 -77.721899,162.2629566 -77.721899,162.2611198 -77.721899,162.259283 -77.721899,162.2574462 -77.721899,162.2556094 -77.721899,162.2537726 -77.721899,162.2519358 -77.721899,162.250099 -77.721899,162.250099 -77.7217019,162.250099 -77.7215048,162.250099 -77.7213077,162.250099 -77.7211106,162.250099 -77.7209135,162.250099 -77.7207164,162.250099 -77.7205193,162.250099 -77.7203222,162.250099 -77.7201251,162.250099 -77.719928))"], "date_created": "Tue, 07 May 2019 00:00:00 GMT", "description": "Blood Falls is a hypersaline, iron\u2010rich discharge at the terminus of the Taylor Glacier in the McMurdo Dry Valleys, Antarctica. In November 2014, brine in a conduit within the glacier was penetrated and sampled using clean\u2010entry techniques and a thermoelectric melting probe called the IceMole. We analyzed the englacial brine sample for filterable iron (fFe), total Fe, major cations and anions, nutrients, organic carbon, and perchlorate. In addition, aliquots were analyzed for minor and trace elements and isotopes including \u03b4D and \u03b418O of water, \u03b434S and \u03b418O of sulfate, 234U, 238U, \u03b411B, 87Sr/86Sr, and \u03b481Br. These measurements were made in order to (1) determine the source and geochemical evolution of the brine and (2) compare the chemistry of the brine to that of nearby hypersaline lake waters and previous supraglacially sampled collections of Blood Falls outflow that were interpreted as end\u2010member brines.", "east": 162.268467, "geometry": ["POINT(162.259283 -77.7209135)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Brine", "locations": "Antarctica", "north": -77.719928, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Lyons, W. Berry; Gardner, Christopher B.", "project_titles": "Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys", "projects": [{"proj_uid": "p0000002", "repository": "USAP-DC", "title": "Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.721899, "title": "The Geochemistry of englacial brine from Taylor Glacier, Antarctica.", "uid": "601179", "west": 162.250099}, {"awards": "0838947 Tulaczyk, Slawek", "bounds_geometry": ["POLYGON((-165.28 -84.24,-165.086 -84.24,-164.892 -84.24,-164.698 -84.24,-164.504 -84.24,-164.31 -84.24,-164.116 -84.24,-163.922 -84.24,-163.728 -84.24,-163.534 -84.24,-163.34 -84.24,-163.34 -84.252,-163.34 -84.264,-163.34 -84.276,-163.34 -84.288,-163.34 -84.3,-163.34 -84.312,-163.34 -84.324,-163.34 -84.336,-163.34 -84.348,-163.34 -84.36,-163.534 -84.36,-163.728 -84.36,-163.922 -84.36,-164.116 -84.36,-164.31 -84.36,-164.504 -84.36,-164.698 -84.36,-164.892 -84.36,-165.086 -84.36,-165.28 -84.36,-165.28 -84.348,-165.28 -84.336,-165.28 -84.324,-165.28 -84.312,-165.28 -84.3,-165.28 -84.288,-165.28 -84.276,-165.28 -84.264,-165.28 -84.252,-165.28 -84.24))"], "date_created": "Sun, 09 Sep 2018 00:00:00 GMT", "description": "This dataset contains ice-shelf basal melt rates and vertical strain rates for 11 sites near the Whillans Ice Stream grounding line. These rates were determined using Autonomous Phase-Sensitive Radar. Data processing is described in Begeman et al. 2018, JGR Oceans. These sites are concentrated within an embayment of the Ross Ice Shelf. These melt rates and strain rates were determined over periods ranging from 10 to 38 days in December 2014 to January 2015. ", "east": -163.34, "geometry": ["POINT(-164.31 -84.3)"], "keywords": "Antarctica; Flexure Zone; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Ice-Shelf Basal Melting; Ice-Shelf Strain Rate", "locations": "Antarctica", "north": -84.24, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Begeman, Carolyn", "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": -84.36, "title": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line", "uid": "601122", "west": -165.28}, {"awards": "1443126 MacAyeal, Douglas", "bounds_geometry": ["POLYGON((165.911079 -77.872851,165.941267 -77.872851,165.971455 -77.872851,166.001643 -77.872851,166.031831 -77.872851,166.062019 -77.872851,166.092207 -77.872851,166.122395 -77.872851,166.152583 -77.872851,166.182771 -77.872851,166.212959 -77.872851,166.212959 -77.8781411,166.212959 -77.8834312,166.212959 -77.8887213,166.212959 -77.8940114,166.212959 -77.8993015,166.212959 -77.9045916,166.212959 -77.9098817,166.212959 -77.9151718,166.212959 -77.9204619,166.212959 -77.925752,166.182771 -77.925752,166.152583 -77.925752,166.122395 -77.925752,166.092207 -77.925752,166.062019 -77.925752,166.031831 -77.925752,166.001643 -77.925752,165.971455 -77.925752,165.941267 -77.925752,165.911079 -77.925752,165.911079 -77.9204619,165.911079 -77.9151718,165.911079 -77.9098817,165.911079 -77.9045916,165.911079 -77.8993015,165.911079 -77.8940114,165.911079 -77.8887213,165.911079 -77.8834312,165.911079 -77.8781411,165.911079 -77.872851))"], "date_created": "Tue, 04 Sep 2018 00:00:00 GMT", "description": "During the melt seasons of 2015/6 and 2016/7, water pressure gages were deployed on the McMurdo Ice Shelf to observe water depth in supraglacial lakes and streams. This was done in support of research directed toward understanding how filling and draining supraglacial lakes would induce ice-shelf flexure and fracture.", "east": 166.212959, "geometry": ["POINT(166.062019 -77.8993015)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Snow/ice; Snow/Ice; Subglacial And Supraglacial Water Depth; Supraglacial Lake; Supraglacial Meltwater; Water Depth", "locations": "Antarctica", "north": -77.872851, "nsf_funding_programs": "Antarctic Glaciology", "persons": "MacAyeal, Douglas; Banwell, Alison", "project_titles": "Impact of Supraglacial Lakes on Ice-Shelf Stability", "projects": [{"proj_uid": "p0000138", "repository": "USAP-DC", "title": "Impact of Supraglacial Lakes on Ice-Shelf Stability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.925752, "title": "Supraglacial Lake Depths on McMurdo Ice Shelf, Antarctica", "uid": "601116", "west": 165.911079}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"], "date_created": "Thu, 20 Apr 2017 00:00:00 GMT", "description": "Using data from the Transantarctic Mountains (TAMs) Northern Network, shear-wave splitting analysis has been employed to constrain azimuthal anisotropy beneath a portion of the northern TAMs. Splitting measurements were made for PKS, SKS, and SKKS phases with the eigenvalue method in SplitLab. The results show two distinct geographic regions of anisotropy: one behind the TAMs front and the other along the Ross Sea coastline. The anisotropic structure behind the TAMs front is best attributed to relict fabric associated with past tectonic episodes. Along the coastline, the anisotropy is interpreted to reflect mantle flow associated with rift-related decompression melting and Cenozoic extension.", "east": 165.120012, "geometry": ["POINT(159.223506 -74.6349495)"], "keywords": "Antarctica; Geology/Geophysics - Other; GPS; Sample/collection Description; Sample/Collection Description; Seismology; Shearwave Spitting; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -73.032547, "nsf_funding_programs": null, "persons": "Hansen, Samantha", "project_titles": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "projects": [{"proj_uid": "p0000300", "repository": "USAP-DC", "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains", "uid": "601019", "west": 153.327}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"], "date_created": "Thu, 20 Apr 2017 00:00:00 GMT", "description": "Using data from the Transantarctic Mountains (TAMs) Northern Network, the shear wave velocity structure beneath the northern TAMs was investigated with surface wave tomography. Rayleigh wave phase velocities were calculated using a two-plane wave approximation and were then inverted for shear velocity structure. The resulting model shows a low velocity zone (~4.24 km/s) at ~160 km depth offshore and adjacent to Mt. Melbourne that extends inland and vertically upwards to ~100 km depth beneath the northern TAMs and Victoria Land. Another low velocity zone (~4.16-4.24 km/s) is also seen at ~150 km depth beneath Ross Island, and relatively slow velocities (~4.24-4.32 km/s) along the Terror Rift connect the two low velocity zones. This structure has been interpreted to reflect rift-related decompression melting along the TAMs front, which would provide thermal buoyancy to uplift the mountain range.", "east": 165.120012, "geometry": ["POINT(159.223506 -74.6349495)"], "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -73.032547, "nsf_funding_programs": null, "persons": "Hansen, Samantha", "project_titles": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "projects": [{"proj_uid": "p0000300", "repository": "USAP-DC", "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "uid": "601018", "west": 153.327}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"], "date_created": "Thu, 06 Apr 2017 00:00:00 GMT", "description": "Stretching ~3,500 km across Antarctica, with peak elevations up to 4,500 m, the Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth and represent a tectonic boundary between the East Antarctica (EA) craton and the West Antarctic Rift System. The origin and uplift mechanism associated with the TAMs is controversial, and multiple models have been proposed. Seismic investigations of the TAMs\u0027 subsurface structure can provide key constraints to help evaluate these models, but previous studies have been primarily focused only on the central TAMs near Ross Island. Using data from the new 15-station Transantarctic Mountain Northern Network as well as data from several smaller networks, this study investigates the upper mantle velocity structure beneath a previously unexplored portion of the northern TAMs through regional body wave tomography. Relative travel-times were calculated for 11,182 P-wave and 8,285 S-wave arrivals from 790 and 581 Mw \u2265 5.5 events, respectively, using multi-channel cross correlation, and these data were then inverted for models of the upper mantle seismic structure. Resulting P- and S-wave tomography images reveal two focused low velocity anomalies beneath Ross Island (RI; \u03b4VP \u2248 -2.0%; \u03b4VS \u2248 -1.5% to -4.0%) and Terra Nova Bay (TNB; \u03b4VP \u2248 -1.5% to -2.0%; \u03b4VS \u2248 -1.0% to -4.0%) that extend to depths of ~200 and ~150 km, respectively. The RI and TNB slow anomalies also extend ~50-100 km laterally beneath the TAMs front and sharply abut fast velocities beneath the EA craton (\u03b4VP \u2248 0.5% to 2%; \u03b4VS \u2248 1.5% to 4.0%). A low velocity region (\u03b4VP \u2248 -1.5%), centered at ~150 km depth beneath the Terror Rift (TR) and primarily constrained within the Victoria Land Basin, connects the RI and TNB anomalies. The focused low velocities are interpreted as regions of partial melt and buoyancy-driven upwelling, connected by a broad region of slow (presumably warm) upper mantle associated with Cenozoic extension along the TR. Dynamic topography estimates based on the imaged S-wave velocity perturbations are consistent with observed surface topography in the central and northern TAMs, thereby providing support for uplift models that advocate for thermal loading and a flexural origin for the mountain range.", "east": 165.120012, "geometry": ["POINT(159.223506 -74.6349495)"], "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -73.032547, "nsf_funding_programs": null, "persons": "Hansen, Samantha", "project_titles": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "projects": [{"proj_uid": "p0000300", "repository": "USAP-DC", "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography", "uid": "601017", "west": 153.327}, {"awards": "1043761 Young, Duncan", "bounds_geometry": ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"], "date_created": "Mon, 20 Feb 2017 00:00:00 GMT", "description": "GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading \"#\" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GMGEO2 contains line based data (in ASCII space delimited txt files) relating to magnetic anomaly. The raw data was obtained by a tail mounted Geometrics G-823A magnetometer. No heading correction, cross over correction, continuation or base correction have been applied. Data with significant geomagnetic activity (restricted to 07-Dec-2014 and 23-Dec-2014) were removed.", "east": -110.0, "geometry": ["POINT(-133 -77.25)"], "keywords": "Antarctica; Gimble; Glaciers/ice Sheet; Glaciers/Ice Sheet; Magnetic; Marie Byrd Land; Navigation; Potential Field; Solid Earth", "locations": "Marie Byrd Land; Antarctica", "north": -74.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Young, Duncan A.; Holt, John W.; Blankenship, Donald D.", "project_titles": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)", "projects": [{"proj_uid": "p0000435", "repository": "USAP-DC", "title": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Magnetic anomaly data over central Marie Byrd Land, West Antarctica (GIMBLE.GMGEO2)", "uid": "601002", "west": -156.0}, {"awards": "1043761 Young, Duncan", "bounds_geometry": ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"], "date_created": "Mon, 20 Feb 2017 00:00:00 GMT", "description": "GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading \"#\" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GGCMG2 contains line based data relating to gravity disturbance, processed from raw acceleration and position data by propriety software from Gravimetric Technologies and Novatel. The raw data was obtained a Canadian MicroGravity GT-1A gravimeter in ICP5, and a GT-2A gravimeter in ICP6. Data reduction was led by T. Richter.", "east": -110.0, "geometry": ["POINT(-133 -77.25)"], "keywords": "Antarctica; Gimble; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravity; Marie Byrd Land; Navigation; Potential Field; Solid Earth", "locations": "Marie Byrd Land; Antarctica", "north": -74.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Young, Duncan A.; Holt, John W.; Blankenship, Donald D.", "project_titles": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)", "projects": [{"proj_uid": "p0000435", "repository": "USAP-DC", "title": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Gravity disturbance data over central Marie Byrd Land, West Antarctica (GIMBLE.GGCMG2)", "uid": "601003", "west": -156.0}, {"awards": "1043761 Young, Duncan", "bounds_geometry": ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"], "date_created": "Mon, 20 Feb 2017 00:00:00 GMT", "description": "GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading \"#\" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GR2HI2 contains line based data (in ASCII space delimited txt files) relating to ice thickness, bed elevation and bed reflectivity, extracted from 1-D focused radargrams by semiautomatic interpretation. Data was acquired using HiCARS2 in ICP5, and MARFA in ICP6. Some data loss occurred in ICP6 (in particular F10,F11, and F14), limiting the lines that were focused. Data reduction was led by D. Young and S. Kempf.", "east": -110.0, "geometry": ["POINT(-133 -77.25)"], "keywords": "Airborne Radar; Antarctica; Gimble; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Marie Byrd Land; Navigation; Radar", "locations": "Marie Byrd Land; Antarctica", "north": -74.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Young, Duncan A.; Holt, John W.; Blankenship, Donald D.", "project_titles": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)", "projects": [{"proj_uid": "p0000435", "repository": "USAP-DC", "title": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Ice thickness and related data over central Marie Byrd Land, West Antarctica (GIMBLE.GR2HI2)", "uid": "601001", "west": -156.0}, {"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": "Lake Whillans; Southern Ocean; Antarctica; Ross Sea", "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": "1142162 Stone, John", "bounds_geometry": ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public.", "east": -85.14, "geometry": ["POINT(-94.64 -81.755)"], "keywords": "Antarctica; Be-10; Chemistry:rock; Chemistry:Rock; Cosmogenic Dating; Glaciology; Nunataks; Sample/collection Description; Sample/Collection Description; Solid Earth; Whitmore Mountains", "locations": "Antarctica; Whitmore Mountains", "north": -81.07, "nsf_funding_programs": null, "persons": "Stone, John", "project_titles": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "projects": [{"proj_uid": "p0000335", "repository": "USAP-DC", "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.44, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "uid": "600162", "west": -104.14}, {"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": "Antarctica; Southern Ocean", "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": "0838855 Jacobel, Robert; 0838854 Jacobel, Robert", "bounds_geometry": ["POLYGON((-164 -84.2,-163 -84.2,-162 -84.2,-161 -84.2,-160 -84.2,-159 -84.2,-158 -84.2,-157 -84.2,-156 -84.2,-155 -84.2,-154 -84.2,-154 -84.21,-154 -84.22,-154 -84.23,-154 -84.24,-154 -84.25,-154 -84.26,-154 -84.27,-154 -84.28,-154 -84.29,-154 -84.3,-155 -84.3,-156 -84.3,-157 -84.3,-158 -84.3,-159 -84.3,-160 -84.3,-161 -84.3,-162 -84.3,-163 -84.3,-164 -84.3,-164 -84.29,-164 -84.28,-164 -84.27,-164 -84.26,-164 -84.25,-164 -84.24,-164 -84.23,-164 -84.22,-164 -84.21,-164 -84.2))"], "date_created": "Thu, 30 Oct 2014 00:00:00 GMT", "description": "This data set includes ground-based, gridded, ice-penetrating radar thickness and basal reflection power, along with GPS coordinates, for two areas of Whillans Ice Stream: Subglacial Lake Whillans and the Whillans Ice Stream grounding zone.", "east": -154.0, "geometry": ["POINT(-159 -84.25)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS; Radar; Whillans Ice Stream", "locations": "Antarctica; Whillans Ice Stream", "north": -84.2, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Jacobel, Robert", "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": -84.3, "title": "Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone", "uid": "609594", "west": -164.0}, {"awards": "0838811 Sergienko, Olga", "bounds_geometry": ["POINT(0 -78)"], "date_created": "Mon, 14 Apr 2014 00:00:00 GMT", "description": "This data set consists of outputs of several numerical models simulating ice stream flow over undulated bed, interaction of ice stream flow, and subglacial and supraglacial hydraulic systems. All simulations are performed for idealized geometries using finite-element models.", "east": 0.0, "geometry": ["POINT(0 -78)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; Ice Thickness; Ice Velocity", "locations": "Antarctica", "north": -78.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Sergienko, Olga", "project_titles": "Model Investigation of Ice Stream/Subglacial Lake Systems", "projects": [{"proj_uid": "p0000045", "repository": "USAP-DC", "title": "Model Investigation of Ice Stream/Subglacial Lake Systems"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Interaction of Ice Stream Flow with Heterogeneous Beds", "uid": "609583", "west": 0.0}, {"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": "Transantarctic Mountains; Antarctica", "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; Wilkes Land; Prydz Bay; George V 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": "0739681 Murray, Alison; 0739698 Doran, Peter", "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": "0636724 Blankenship, Donald", "bounds_geometry": ["POLYGON((-120 -75,-117 -75,-114 -75,-111 -75,-108 -75,-105 -75,-102 -75,-99 -75,-96 -75,-93 -75,-90 -75,-90 -75.5,-90 -76,-90 -76.5,-90 -77,-90 -77.5,-90 -78,-90 -78.5,-90 -79,-90 -79.5,-90 -80,-93 -80,-96 -80,-99 -80,-102 -80,-105 -80,-108 -80,-111 -80,-114 -80,-117 -80,-120 -80,-120 -79.5,-120 -79,-120 -78.5,-120 -78,-120 -77.5,-120 -77,-120 -76.5,-120 -76,-120 -75.5,-120 -75))"], "date_created": "Mon, 21 May 2012 00:00:00 GMT", "description": "This data set contains subglacial water flow paths beneath Thwaites Glacier, West Antarctica, interpreted from ice thickness and bed elevation measurements collected between 7 December 2004 and 31 January 2005 by the Airborne Geophysical Survey of the Amundsen Embayment (AGASEA) expedition. Data consist of an ASCII text file with geographical coordinates, hydraulic head, and bed and surface elevations, and a corresponding .pdf map.\n\nData are available via FTP.", "east": -90.0, "geometry": ["POINT(-105 -77.5)"], "keywords": "AGASEA; Airborne Radar; Antarctica; Elevation; Flow Paths; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Thwaites Glacier", "locations": "Antarctica; Thwaites Glacier", "north": -75.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Carter, Sasha P.; Young, Duncan A.; Blankenship, Donald D.", "project_titles": "Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System", "projects": [{"proj_uid": "p0000174", "repository": "USAP-DC", "title": "Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Subglacial water flow paths under Thwaites Glacier, West Antarctica", "uid": "609518", "west": -120.0}, {"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": "Antarctica; Southern Ocean; Gamburtsev Mountains; Prydz Bay", "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": "0538674 Winebrenner, Dale", "bounds_geometry": ["POLYGON((68.4 -75.7,69.61 -75.7,70.82 -75.7,72.03 -75.7,73.24 -75.7,74.45 -75.7,75.66 -75.7,76.87 -75.7,78.08 -75.7,79.29 -75.7,80.5 -75.7,80.5 -76.04,80.5 -76.38,80.5 -76.72,80.5 -77.06,80.5 -77.4,80.5 -77.74,80.5 -78.08,80.5 -78.42,80.5 -78.76,80.5 -79.1,79.29 -79.1,78.08 -79.1,76.87 -79.1,75.66 -79.1,74.45 -79.1,73.24 -79.1,72.03 -79.1,70.82 -79.1,69.61 -79.1,68.4 -79.1,68.4 -78.76,68.4 -78.42,68.4 -78.08,68.4 -77.74,68.4 -77.4,68.4 -77.06,68.4 -76.72,68.4 -76.38,68.4 -76.04,68.4 -75.7))"], "date_created": "Mon, 01 Aug 2011 00:00:00 GMT", "description": "This data set consists of inferred accumulation rates from three radar layers (26, 35 and 41 thousand years old) in the Vostok Subglacial Lake region. Accumulation rates were inferred using Local-Layer Approximation (LLA), which assumes that the strain-rate history of a particle traveling through the ice sheet can be approximated by the vertical strain-rate profile at the current position of the particle, which the researchers assume to be uniform. Parameters include location, in latitude and longitude, polar stereographic coordinates, and local grid X and Y coordinates, along with layer age, in thousands of years (ka), and inferred accumulation rate (cm/a). The data cover a 150 by 350 km area.\n\nData are available via FTP, as a text file (.txt) with columns in comma separated value format.", "east": 80.5, "geometry": ["POINT(74.45 -77.4)"], "keywords": "Accumulation Rate; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok", "locations": "Antarctica; Lake Vostok", "north": -75.7, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Macgregor, Joseph A.; Matsuoka, Kenichi; Studinger, Michael S.; Waddington, Edwin D.; Winebrenner, Dale", "project_titles": "Collaborative Research: Deciphering the Deep Ice and the Ice-water Interface over Lake Vostok Using Existing Radar Data", "projects": [{"proj_uid": "p0000090", "repository": "USAP-DC", "title": "Collaborative Research: Deciphering the Deep Ice and the Ice-water Interface over Lake Vostok Using Existing Radar Data"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.1, "title": "Millennially Averaged Accumulation Rates for Lake Vostok", "uid": "609500", "west": 68.4}, {"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": "Southern Ocean; Antarctica; Gamburtsev Mountains", "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": "0338151 Raymond, Charles", "bounds_geometry": ["POINT(-112.09 -79.47)"], "date_created": "Tue, 15 Jun 2010 00:00:00 GMT", "description": "This data set contains the results of a model study of spatial variations of ice temperature and subglacial conditions using available ice-penetrating radar data around a future deep ice coring site near the Ross and Amundsen flow divide of West Antarctic Ice Sheet. The model data are based on radar data collected by the Support Office of Aerogeophysical Research (SOAR) at the University of Texas, and the University of Washington, in 2000. The data include values for attenuation estimates for individual radar profiles.\n\nData are available via FTP in MATLAB (.mat) and Portable Document (.pdf) formats.", "east": -112.09, "geometry": ["POINT(-112.09 -79.47)"], "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; WAIS Divide", "locations": "WAIS Divide; Antarctica", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Raymond, Charles; Matsuoka, Kenichi", "project_titles": "Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data", "projects": [{"proj_uid": "p0000017", "repository": "USAP-DC", "title": "Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica", "uid": "609470", "west": -112.09}, {"awards": "0440523 Baker, Ian; 0538195 Marone, Chris; 0424589 Gogineni, S. Prasad", "bounds_geometry": ["POINT(-147.753056 61.781667)", "POINT(-83.006944 40.067222)", "POINT(147.758889 61.779444)"], "date_created": "Wed, 14 Apr 2010 00:00:00 GMT", "description": "This data set includes the results of laboratory experiments examining the constitutive properties of subglacial till, under dynamic stressing. The data include the results of shear strain and stress experiments. Testing was carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, allowing both sliding and microstructural processes to be studied in detail. Till samples were collected from Matanuska, Alaska and from Caesar till at the Laurentide Ice Sheet. \n\nThe data are available via FTP in ASCII text format (.txt).", "east": 147.758889, "geometry": ["POINT(-147.753056 61.781667)", "POINT(-83.006944 40.067222)", "POINT(147.758889 61.779444)"], "keywords": "Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Shear Stress; Solid Earth; Strain", "locations": null, "north": 61.781667, "nsf_funding_programs": "Antarctic Glaciology", "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": 40.067222, "title": "Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till", "uid": "609460", "west": -147.753056}, {"awards": "9319379 Blankenship, Donald; 9911617 Blankenship, Donald", "bounds_geometry": ["POLYGON((-160 -70,-142.5 -70,-125 -70,-107.5 -70,-90 -70,-72.5 -70,-55 -70,-37.5 -70,-20 -70,-2.5 -70,15 -70,15 -72,15 -74,15 -76,15 -78,15 -80,15 -82,15 -84,15 -86,15 -88,15 -90,-2.5 -90,-20 -90,-37.5 -90,-55 -90,-72.5 -90,-90 -90,-107.5 -90,-125 -90,-142.5 -90,-160 -90,-160 -88,-160 -86,-160 -84,-160 -82,-160 -80,-160 -78,-160 -76,-160 -74,-160 -72,-160 -70))"], "date_created": "Fri, 06 Feb 2009 00:00:00 GMT", "description": "This data set is an Antarctic radar-based subglacial lake classification collection, which focuses on the radar reflection properties of each given lake.\n\nThe Subglacial lakes are separated into four categories specified by radar reflection properties. Additional information includes: latitude, longitude, length (in kilometers), hydro-potential (in meters), bed elevation (in meters above WGS84), and ice thickness (in meters).\n\nSource data used to compile this data set were collected between 1998 and 2001. Data are available via FTP as a Microsoft Excel Spreadsheet (XLS), and Tagged Image File Format (TIF).", "east": 15.0, "geometry": ["POINT(-72.5 -80)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Lake", "locations": "Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Blankenship, Donald D.; Holt, John W.; Carter, Sasha P.", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Antarctic Subglacial Lake Classification Inventory", "uid": "609336", "west": -160.0}, {"awards": "0816934 Thomson, Stuart", "bounds_geometry": ["POLYGON((65 -66,72.9 -66,80.8 -66,88.7 -66,96.6 -66,104.5 -66,112.4 -66,120.3 -66,128.2 -66,136.1 -66,144 -66,144 -66.3,144 -66.6,144 -66.9,144 -67.2,144 -67.5,144 -67.8,144 -68.1,144 -68.4,144 -68.7,144 -69,136.1 -69,128.2 -69,120.3 -69,112.4 -69,104.5 -69,96.6 -69,88.7 -69,80.8 -69,72.9 -69,65 -69,65 -68.7,65 -68.4,65 -68.1,65 -67.8,65 -67.5,65 -67.2,65 -66.9,65 -66.6,65 -66.3,65 -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": 144.0, "geometry": ["POINT(104.5 -67.5)"], "keywords": "Antarctica; Fission Track Thermochronology; Gamburtsev Mountains; Geochronology; Solid Earth", "locations": "Gamburtsev Mountains; Antarctica", "north": -66.0, "nsf_funding_programs": null, "persons": "Thomson, Stuart", "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": "600089", "west": 65.0}, {"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": "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; Prydz Bay; Southern Ocean; 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": "0536870 Rogers, Scott", "bounds_geometry": ["POINT(106.8 -72.4667)"], "date_created": "Tue, 01 Jan 2008 00:00:00 GMT", "description": "The large subglacial Lake Vostok in Antarctica is unique ecological site with a novel microbial biota. The temperatures, pressures and lack of light all select for organisms that may not exist anywhere else on Earth. The accretion ice (lake water frozen to the bottom of the lower surface of the glacier) has preserved microbial samples from each region of Lake Vostok as the glacier passes over and into the lake. Thus, without contaminating the lake with microorganisms from the surface, microbes originating from the lake can be collected, transported to the laboratory and studied. Two of the deepest ice cores sections in this project are part of the international allocation. \n\nThe will be shared between four researchers (Sergey Bulat from Russia, Jean-Robert Petit and Daniel Prieur from France, Scott Rogers from USA). The United States team will study, isolate, and characterize bacteria, fungi, and viruses that have been sampled from the lake through the process of ice accretion to the lower surface of 3500+m thick glacier overriding the lake. The project will involve a suite of methods, including molecular, morphological, and cultural. This includes observation and description by fluorescence, light, and electron microscopy, isolation on thirteen separate cultural media, polymerase chain reaction amplification, DNA sequencing, and phylogenetic analyses. Eleven accretion ice core sections, as well as two glacial ice core sections. As well as two glacial ice core sections will be studied. The accretion ice core sections, as well as two glacial ice core sections will be studied. The accretion ice core sections represent all of the major regions of the lake that have been sampled by the accretion process in the vicinity of the Vostok 5G ice core. The broader impacts of the work relate to the impact the results will have on the filed. These long=isolated lakes, deep below the Antarctic ice sheet may contain novel uniquely adapted organisms. Glacial ice contains an enormous diversity of entrapped microbes, some of which may be metabolically active in the ice. The microbes from Lake Vostok are of special interest, since they are adapted to cold, dark, and high pressure. Thus, their enzyme systems and biochemical pathways may be significantly different from those in the microbes that are the subject of current studies. As such, these organisms may form compounds that may have useful applications. Also, study of the accretion ice, and eventually the water, from Lake Vostok will provide a basis for the study of other subglacial lakes. Additionally, study of the microbes in the accretion ice will be useful to those planning to study analogous systems on ice-covered planets and moons.", "east": 106.8, "geometry": ["POINT(106.8 -72.4667)"], "keywords": "Antarctica; Biota; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrothermal Vent; Lake Vostok; Microbes; Subglacial Lake", "locations": "Antarctica; Lake Vostok", "north": -72.4667, "nsf_funding_programs": null, "persons": "Rogers, Scott O.", "project_titles": "Comprehensive Biological Study of Vostok Accretion Ice", "projects": [{"proj_uid": "p0000566", "repository": "USAP-DC", "title": "Comprehensive Biological Study of Vostok Accretion Ice"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.4667, "title": "Comprehensive Biological Study of Vostok Accretion Ice", "uid": "600052", "west": 106.8}, {"awards": "0230197 Holt, John", "bounds_geometry": ["POLYGON((-134.9 -71.7,-129.86 -71.7,-124.82 -71.7,-119.78 -71.7,-114.74 -71.7,-109.7 -71.7,-104.66 -71.7,-99.62 -71.7,-94.58 -71.7,-89.54 -71.7,-84.5 -71.7,-84.5 -72.7,-84.5 -73.7,-84.5 -74.7,-84.5 -75.7,-84.5 -76.7,-84.5 -77.7,-84.5 -78.7,-84.5 -79.7,-84.5 -80.7,-84.5 -81.7,-89.54 -81.7,-94.58 -81.7,-99.62 -81.7,-104.66 -81.7,-109.7 -81.7,-114.74 -81.7,-119.78 -81.7,-124.82 -81.7,-129.86 -81.7,-134.9 -81.7,-134.9 -80.7,-134.9 -79.7,-134.9 -78.7,-134.9 -77.7,-134.9 -76.7,-134.9 -75.7,-134.9 -74.7,-134.9 -73.7,-134.9 -72.7,-134.9 -71.7))"], "date_created": "Wed, 25 Oct 2006 00:00:00 GMT", "description": "This data set includes 5 km gridded data from the Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) conducted during the 2004-2005 austral summer. Investigators derived maps of the ice sheet surface and subglacial topography, which covers the entire catchments of both the Thwaites Glacier and the Pine Islands Glacier, from airborne survey systems mounted on a Twin Otter aircraft. The surveys had sufficient density to identify critical ice dynamic transitions within the Amundsen Sea Embayment (ASE). \n\nThe ASE is the only major drainage to exhibit significant elevation change over the period of available satellite observations. Modeling of the Western Antarctic Ice Sheet (WAIS) deglaciation pinpointed the Pine Island Glacier and the Thwaites Glacier, which comprise a major portion of the ASE, as the most vulnerable features of the WAIS. Present knowledge of the ice thickness and subglacial boundary conditions in the ASE are insufficient to understand its evolution or its sensitivity to climatic change, and it is not yet determined whether these changes are evidence of ongoing deglaciation or simply a fluctuation that does not threaten the equilibrium of the ice sheet. This research will support the efforts of a community of United States and international researchers to assess the present and predict the future behavior of the ice sheet in the ASE. \n\nThese data are available via FTP.", "east": -84.5, "geometry": ["POINT(-109.7 -76.7)"], "keywords": "AGASEA; Airborne Radar; Amundsen Sea; Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Solid Earth", "locations": "Antarctica; Amundsen Sea", "north": -71.7, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Holt, John W.; Blankenship, Donald D.; Morse, David L.; Vaughan, David G.; Corr, Hugh F. J.; Young, Duncan A.", "project_titles": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA)", "projects": [{"proj_uid": "p0000243", "repository": "USAP-DC", "title": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.7, "title": "Subglacial Topography: Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica", "uid": "609292", "west": -134.9}, {"awards": "9318121 Anandakrishnan, Sridhar; 9222121 Dalziel, Ian", "bounds_geometry": ["POINT(106.48 -72.28)"], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "These data describe the d18O of O2, d15N of N2, d18Oatm, and O2/N2 ratios of trapped gases in the Vostok ice core from East Antarctica. The investigator used a mass spectrometer to measure gas concentrations and isotopic compositions. Data extend to approximately 420,000 years ago. Two different age models are included.\n\nData are available in tab-delimited ASCII format via ftp.", "east": 106.48, "geometry": ["POINT(106.48 -72.28)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciology; Ice Core Records; Lake Vostok; Paleoclimate; UPLC-Q-TOF; Vostok Ice Core", "locations": "Lake Vostok; Antarctica", "north": -72.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Bender, Michael", "project_titles": "Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test", "projects": [{"proj_uid": "p0000150", "repository": "USAP-DC", "title": "Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.28, "title": "Concentration and Isotopic Composition of O2 and N2 in Trapped Gases of the Vostok Ice Core", "uid": "609107", "west": 106.48}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Ensemble of subglacial topography beneath Denman Glacier generated by geostatistical Monte Carlo Markov Chain under mass conservation principle
|
2324092 |
2025-04-21 | Shao, Niya; MacKie, Emma; Michael, Field; McCormack, Felicity | No project link provided | This dataset is a result of a study which uses Monte Carlo Markov Chain and geostatistics to infer subglacial topography from sparse bed elevation measurements. The dataset consists of 40 equally probable realizations of subglacial topography in the Denman region. Each of the realizations is constrained by conservation of ice mass (mass conservation), complies with bed elevation measurements from bedmap3 dataset, and has a realistic topographic roughness. The topography has 1 kilometer times 1 kilometer resolution on a regular grid in polar stereographic projection (EPSG 3412). | ["POLYGON((95 -65,96 -65,97 -65,98 -65,99 -65,100 -65,101 -65,102 -65,103 -65,104 -65,105 -65,105 -65.7,105 -66.4,105 -67.1,105 -67.8,105 -68.5,105 -69.2,105 -69.9,105 -70.6,105 -71.3,105 -72,104 -72,103 -72,102 -72,101 -72,100 -72,99 -72,98 -72,97 -72,96 -72,95 -72,95 -71.3,95 -70.6,95 -69.9,95 -69.2,95 -68.5,95 -67.8,95 -67.1,95 -66.4,95 -65.7,95 -65))"] | ["POINT(100 -68.5)"] | false | false |
Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps
|
2423761 2042495 |
2025-03-17 | Piccione, Gavin |
EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica Collaborative Research: Reconstructing East Antarctica’s Past Response to Climate using Subglacial Precipitates |
This dataset includes geochemical analyses of carbonate nodules collected at Elephant Moraine and the Pensacola Mountains, East Antarctica. Oxygen and uranium-series isotope analyses indicate that these carbonates precipitated from glacial meltwater during deglacial periods in the late Pleistocene. Carbonate δ13C values as low as -32.75 ‰ identify thermogenic methane as a primary carbon source, while clumped isotope measurements indicate formation temperatures of 12 - 20˚C, consistent with a geothermal origin. Lipid biomarker analyses further show that organic matter preserved in the nodules is highly thermally matured. These findings indicate that deep-sourced thermogenic methane migrated as hydrocarbon seeps to shallow pore spaces within basal sediments, demonstrating that geothermally active areas can be hotspots for methane accumulation below the Antarctic Ice Sheet. This material is based on services provided by the Polar Rock Repository with support from the National Science Foundation, under Cooperative Agreement OPP-2137467. | ["POLYGON((-180 -75,-144 -75,-108 -75,-72 -75,-36 -75,0 -75,36 -75,72 -75,108 -75,144 -75,180 -75,180 -76.5,180 -78,180 -79.5,180 -81,180 -82.5,180 -84,180 -85.5,180 -87,180 -88.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -88.5,-180 -87,-180 -85.5,-180 -84,-180 -82.5,-180 -81,-180 -79.5,-180 -78,-180 -76.5,-180 -75))"] | ["POINT(0 -89.999)"] | false | false |
Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming
|
2042495 |
2025-03-05 | Gagliardi, Jessica |
Collaborative Research: Reconstructing East Antarctica’s Past Response to Climate using Subglacial Precipitates |
This dataset contains U-series, d18O, d13C and 87Sr/86Sr data from 25 subglacial calcite precipitates from locations around the Antarctic ice sheet, primarily outlet glaciers near the ice sheet margins and nunataks in the Transantarctic mountains. Lat-lon data for each sample is given as well. | ["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 |
Ice-penetrating radar data from the northern embayment of the Mt. Murphy massif
|
1738989 |
2024-11-13 | Balco, Greg; Campbell, Seth; Goehring, Brent |
NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System |
Contains ice-penetrating radar data (10, 100, and 400 MHz) from the north side of the Mt. Murphy massif. Most of these data are closely spaced lines used for reconnaissance and site selection for a subglacial bedrock recovery drilling project very close to the ice margin at the north ridge of Kay Peak, a sub-peak of the massif. In addition, there are several longer exploratory lines that cross the embayment between the massif and the Crosson Ice Shelf, some of which may cross grounding lines. | ["POLYGON((-110.9665 -75.1967,-110.92041 -75.1967,-110.87432 -75.1967,-110.82822999999999 -75.1967,-110.78214 -75.1967,-110.73605 -75.1967,-110.68996 -75.1967,-110.64386999999999 -75.1967,-110.59778 -75.1967,-110.55169000000001 -75.1967,-110.5056 -75.1967,-110.5056 -75.20331,-110.5056 -75.20992000000001,-110.5056 -75.21653,-110.5056 -75.22314,-110.5056 -75.22975,-110.5056 -75.23636,-110.5056 -75.24297,-110.5056 -75.24958,-110.5056 -75.25619,-110.5056 -75.2628,-110.55169000000001 -75.2628,-110.59778 -75.2628,-110.64386999999999 -75.2628,-110.68996 -75.2628,-110.73605 -75.2628,-110.78214 -75.2628,-110.82822999999999 -75.2628,-110.87432 -75.2628,-110.92041 -75.2628,-110.9665 -75.2628,-110.9665 -75.25619,-110.9665 -75.24958,-110.9665 -75.24297,-110.9665 -75.23636,-110.9665 -75.22975,-110.9665 -75.22314,-110.9665 -75.21653,-110.9665 -75.20992000000001,-110.9665 -75.20331,-110.9665 -75.1967))"] | ["POINT(-110.73605 -75.22975)"] | 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 |
Firn and Ice Density at Winkie Nunatak
|
2317097 |
2024-10-02 | Venturelli, Ryan |
NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System |
This data set contains an ice and firn density profile from Winkie Nunatak, West Antarctica. These data were collected when drilling a sub-ice access hole with an Eclipse drill in preparation for Winkie drill collection of subglacial bedrock. | ["POLYGON((-99.793 -74.857,-99.7882 -74.857,-99.7834 -74.857,-99.77860000000001 -74.857,-99.77380000000001 -74.857,-99.769 -74.857,-99.7642 -74.857,-99.7594 -74.857,-99.75460000000001 -74.857,-99.74980000000001 -74.857,-99.745 -74.857,-99.745 -74.8583,-99.745 -74.8596,-99.745 -74.8609,-99.745 -74.8622,-99.745 -74.8635,-99.745 -74.8648,-99.745 -74.8661,-99.745 -74.8674,-99.745 -74.8687,-99.745 -74.87,-99.74980000000001 -74.87,-99.75460000000001 -74.87,-99.7594 -74.87,-99.7642 -74.87,-99.769 -74.87,-99.77380000000001 -74.87,-99.77860000000001 -74.87,-99.7834 -74.87,-99.7882 -74.87,-99.793 -74.87,-99.793 -74.8687,-99.793 -74.8674,-99.793 -74.8661,-99.793 -74.8648,-99.793 -74.8635,-99.793 -74.8622,-99.793 -74.8609,-99.793 -74.8596,-99.793 -74.8583,-99.793 -74.857))"] | ["POINT(-99.769 -74.8635)"] | 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 |
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 |
U-Series Comminution Age Constraints on Taylor Valley Erosion Collaborative Research: Reconstructing East Antarctica’s Past Response to Climate using Subglacial Precipitates |
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 |
East Antarctic Seismicity from different Automated Event Detection Algorithms
|
1914698 |
2024-01-24 | Hansen, Samantha; Ho, Long; Walter, Jacob |
Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes
Subglacial Basin (RESISSt) |
As seismic data availability increases, the necessity for automated processing techniques has become increasingly evident. Expanded geophysical datasets collected over the past several decades across Antarctica provide excellent resources to evaluate different event detection approaches. We have used the traditional Short-Term Average/Long-Term Average (STA/LTA) algorithm to catalogue seismic data recorded by 19 stations in East Antarctica between 2012 and 2015. However, the complexities of the East Antarctic dataset, including low magnitude events and phenomena such as icequakes, warrant more advanced automated detection techniques. Therefore, we have also applied template matching as well as several deep learning algorithms, including Generalized Phase Detection (GPD), PhaseNet, BasicPhaseAE, and EQTransformer (EQT), to identify seismic phases within our dataset. Our goal was not only to increase the volume of detectable seismic events but also to gain insights into the effectiveness of these different automated approaches. Our assessment evaluated the completeness of the newly generated catalogs, the precision of identified event locations, and the quality of the picks. The final events corresponding to each of our three catalogs (based on STA/LTA, template matching, and machine learning, respectively) are listed in the provided files. | ["POLYGON((148 -71.5,150.4 -71.5,152.8 -71.5,155.2 -71.5,157.6 -71.5,160 -71.5,162.4 -71.5,164.8 -71.5,167.2 -71.5,169.6 -71.5,172 -71.5,172 -72.15,172 -72.8,172 -73.45,172 -74.1,172 -74.75,172 -75.4,172 -76.05,172 -76.7,172 -77.35,172 -78,169.6 -78,167.2 -78,164.8 -78,162.4 -78,160 -78,157.6 -78,155.2 -78,152.8 -78,150.4 -78,148 -78,148 -77.35,148 -76.7,148 -76.05,148 -75.4,148 -74.75,148 -74.1,148 -73.45,148 -72.8,148 -72.15,148 -71.5))"] | ["POINT(160 -74.75)"] | false | false |
Full Waveform Ambient Noise Tomography for East Antarctica
|
1914698 |
2024-01-24 | Hansen, Samantha; Emry, Erica |
Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes
Subglacial Basin (RESISSt) |
Recent investigations in polar environments have examined solid-Earth-ice-sheet feedbacks and have emphasized that glacial isostatic adjustment, tectonic, and geothermal forcings exert first-order control on the physical conditions at and below the ice-bed interface and must be taken into account when evaluating ice-sheet evolution. However, the solid-Earth structure beneath much of Antarctica is still poorly constrained given the sparse distribution of seismic stations across the continent and the generally low seismicity rate. One region of particular interest is the Wilkes Subglacial Basin (WSB) in East Antarctica. During the mid-Pliocene warm period, the WSB may have contributed 3-4 m to the estimated 20 m rise in sea-level, indicating that this region could also play an important role in future warming scenarios. However, the WSB may have experienced notable bedrock uplift since the Pliocene; therefore, past geologic inferences of instability may not serve as a simple analogue for the future. Using records of ambient seismic noise recorded by both temporary and long-term seismic networks, along with a full-waveform tomographic inversion technique, we have developed improved images of the lithospheric structure beneath East Antarctica, including the WSB. Empirical Green’s Functions with periods between 40 and 340 s have been extracted using a frequency-time normalization technique, and a finite-difference approach with a spherical grid has been employed to numerically model synthetic seismograms. Associated sensitivity kernels have also been constructed using a scattering integral method. Our results suggest the WSB is underlain by slow seismic velocities, with faster seismic structure beneath the adjacent Transantarctic Mountains and the Belgica Subglacial Highlands. This may indicate that the WSB is associated with a region of thinner lithosphere, possibly associated with prior continental rifting. The seismic heterogeneity highlighted in our model could have significant implications for understanding the geodynamic origin of WSB topography and its influence on ice-sheet behavior. The model file and associated plotting scripts are provided. | ["POLYGON((90 -65,99 -65,108 -65,117 -65,126 -65,135 -65,144 -65,153 -65,162 -65,171 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,171 -90,162 -90,153 -90,144 -90,135 -90,126 -90,117 -90,108 -90,99 -90,90 -90,90 -87.5,90 -85,90 -82.5,90 -80,90 -77.5,90 -75,90 -72.5,90 -70,90 -67.5,90 -65))"] | ["POINT(135 -77.5)"] | 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 |
In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers
|
1738989 |
2023-07-10 | Venturelli, Ryan; Goehring, Brent; Balco, Gregory |
NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System |
Included in this dataset are in situ carbon-14 concentrations for a series of bedrock cores recovered from the subglacial extension of Kay Peak, a grounding-line-proximal ridge of the volcanic edifice Mount Murphy (near Thwaites and Pope glaciers). Concentrations measured in these bedrock samples have been used in the associated publication to demonstrate that the Thwaites-Pope glacier system was thinner in the Holocene than it is today. | ["POINT(-110.96038 -75.21526)"] | ["POINT(-110.96038 -75.21526)"] | false | false |
200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica
|
2317097 |
2023-03-24 | Braddock, Scott |
NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System |
This data set contains unprocessed radar profiles collected with a GSSI 200 MHz Hyperstacking antenna near Winkie Nunatak, West Antarctica. This data was collected to estimate depth-to-bedrock along a subglacial ridge line at depths between 20 - 120 meters. | ["POLYGON((-99.793 -74.857,-99.7882 -74.857,-99.7834 -74.857,-99.77860000000001 -74.857,-99.77380000000001 -74.857,-99.769 -74.857,-99.7642 -74.857,-99.7594 -74.857,-99.75460000000001 -74.857,-99.74980000000001 -74.857,-99.745 -74.857,-99.745 -74.8583,-99.745 -74.8596,-99.745 -74.8609,-99.745 -74.8622,-99.745 -74.8635,-99.745 -74.8648,-99.745 -74.8661,-99.745 -74.8674,-99.745 -74.8687,-99.745 -74.87,-99.74980000000001 -74.87,-99.75460000000001 -74.87,-99.7594 -74.87,-99.7642 -74.87,-99.769 -74.87,-99.77380000000001 -74.87,-99.77860000000001 -74.87,-99.7834 -74.87,-99.7882 -74.87,-99.793 -74.87,-99.793 -74.8687,-99.793 -74.8674,-99.793 -74.8661,-99.793 -74.8648,-99.793 -74.8635,-99.793 -74.8622,-99.793 -74.8609,-99.793 -74.8596,-99.793 -74.8583,-99.793 -74.857))"] | ["POINT(-99.769 -74.8635)"] | 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 |
Water column biogeochemical data from Mercer Subglacial Lake
|
1543537 |
2023-02-01 | Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset contains water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (δ2H and δ18O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts. | ["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 |
CTD data from Mercer Subglacial Lake and access borehole
|
1543537 |
2023-01-17 | Dore, John; Priscu, John; Leventer, Amy; Rosenheim, Brad |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset includes binned conductivity, temperature and pressure measurements from Mercer Subglacial Lake and the borehole drilled to access the lake by the SALSA project, as well as additional physical parameters derived from these measurements using the TEOS-10 equation of state. | ["POINT(-149.50134 -84.640287)"] | ["POINT(-149.50134 -84.640287)"] | false | false |
Subglacial Precipitates Record Antarctic Ice Sheet Response to Pleistocene Millennial Climate Cycles
|
2042495 |
2022-08-10 | Piccione, Gavin; Blackburn, Terrence |
Collaborative Research: Reconstructing East Antarctica’s Past Response to Climate using Subglacial Precipitates |
This file includes U-series isotopic and 234U/230Th chronologic data from two chemical precipitates deposited beneath the Antarctic Ice Sheet. Precipitate mineral compositions consist of opal and calcite layers. Sample MA113 was found at Mount Achernar moraine (84.2°S, 161°E), and sample PRR50489 was found at Elephant Moraine (76.3°S, 157.3°E). | [] | [] | false | false |
Support Office for Airborne Research 1 km sampled ice thickness data
|
9319379 |
2022-07-24 | Blankenship, Donald D.; Young, Duncan A.; Kempf, Scott D. | No project link provided | These data represent the 1-km decimated version of the SOAR ice thickness data provided to the Bedmap2 project, collected as part of various projects between 1991 and 2001. It encompasses the Corridor Aerogeophysics of the South East Ross Zone (CASERTZ) surveys of the Byrd Subglacial Basin (BSB), Bindschadler Ice Stream (WAZ/TKD), and the upstream catchments of Kamb Ice Steam and Willians Ice Stream (IRE); targeted West Antarctic glaciology projects (IPB/WAZ/DVD/STI/LIV); corridors across the Transantarctic Mountains to South Pole (PPT) and Dome C (WLK); and a version of the Lake Vostok dataset (LVS). Data were collected as stacked log detected traces by the SOAR TUD IV system with an attached digitizer. The digitizer was significantly updated in 1997 (RTZ6). Data interpretation approaches can be found in Blankenship et al., 2001. Data is in ASCII format. Transects are separated by GMT style segment headers with the transect name. Columns are: 1. Year 2. Day of Year 3. Seconds of Day 4. Longitude (degrees, WGS-84) 5. Latitude (degrees, WGS-84) 6. Easting (meters, EPSG 3031; Polar Stereographic with true scale at 71˚S) 7. Northing (meters, EPSG 3031; Polar Stereographic with true scale at 71˚S) 8. Surface Elevation (meters, WGS-84) - derived where possible from laser data 9. Ice thickness (meters, using a speed of light in air of 299705000 m/s and a refractive index of 1.78; no firn correction) 10. Bed Elevation (meters, WGS-84) - column 8 minus column 9 11. The transect name formatted by Project/Set/Transect | ["POLYGON((-180 -75,-172 -75,-164 -75,-156 -75,-148 -75,-140 -75,-132 -75,-124 -75,-116 -75,-108 -75,-100 -75,-100 -76.5,-100 -78,-100 -79.5,-100 -81,-100 -82.5,-100 -84,-100 -85.5,-100 -87,-100 -88.5,-100 -90,-108 -90,-116 -90,-124 -90,-132 -90,-140 -90,-148 -90,-156 -90,-164 -90,-172 -90,180 -90,172 -90,164 -90,156 -90,148 -90,140 -90,132 -90,124 -90,116 -90,108 -90,100 -90,100 -88.5,100 -87,100 -85.5,100 -84,100 -82.5,100 -81,100 -79.5,100 -78,100 -76.5,100 -75,108 -75,116 -75,124 -75,132 -75,140 -75,148 -75,156 -75,164 -75,172 -75,-180 -75))"] | ["POINT(-180 -82.5)"] | false | false |
Wideband magnetotelluric responses from Whillans Ice Stream, West Antarctica
|
1643917 |
2022-02-25 | Gustafson, Chloe; Key, Kerry; Siegfried, Matthew; Fricker, Helen |
Mapping Antarctic Subglacial Water with Novel Electromagnetic Techniques |
This archive contains magnetotelluric (MT) responses estimated from MT time series data that were collected to study subglacial groundwater beneath Whillans Ice Stream, West Antarctica. Data acquisition took place during the 2018/2019 Antarctic summer field season. 27 MT stations were collected at Whillans Subglacial Lake (SLW) and 16 stations were obtained at its hypothesized downstream outlet to the ocean, Whillans Grounding Zone (WGZ). The MT responses are provided as text files in the .zmm format output by the MT data processing code, but have also been converted to the more widely used .edi text file format for convenience. All sensor orientations are listed as geomagnetic azimuths, which for this region are substantially different than the corresponding geographic azimuths. | ["POLYGON((-163.646 -84.186,-162.58715 -84.186,-161.5283 -84.186,-160.46945 -84.186,-159.4106 -84.186,-158.35175 -84.186,-157.2929 -84.186,-156.23405 -84.186,-155.1752 -84.186,-154.11635 -84.186,-153.0575 -84.186,-153.0575 -84.20871,-153.0575 -84.23142,-153.0575 -84.25413,-153.0575 -84.27684,-153.0575 -84.29955,-153.0575 -84.32226,-153.0575 -84.34497,-153.0575 -84.36768,-153.0575 -84.39039,-153.0575 -84.4131,-154.11635 -84.4131,-155.1752 -84.4131,-156.23405 -84.4131,-157.2929 -84.4131,-158.35175 -84.4131,-159.4106 -84.4131,-160.46945 -84.4131,-161.5283 -84.4131,-162.58715 -84.4131,-163.646 -84.4131,-163.646 -84.39039,-163.646 -84.36768,-163.646 -84.34497,-163.646 -84.32226,-163.646 -84.29955,-163.646 -84.27684,-163.646 -84.25413,-163.646 -84.23142,-163.646 -84.20871,-163.646 -84.186))"] | ["POINT(-158.35175 -84.29955)"] | false | false |
South Pole Lake ApRES Radar
|
1643353 1744649 |
2022-01-06 | Hills, Benjamin |
Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow |
These are ground-based radar data collected from a subglacial lake ~15 km from the geographic South Pole. Data were collected with the Autonomous phase-sensitive Radio Echo Sounder (ApRES) (Nicholls et al., 2015). The intention of this dataset is to be used for vertical velocity structure and interpretation. | ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"] | ["POINT(0 -89.999)"] | false | false |
South Pole Lake GNSS
|
1744649 1643353 |
2022-01-06 | Hills, Benjamin |
Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow |
These are ground-based GNSS data collected from a subglacial lake ~15 km from the geographic South Pole. Data were collected with two separate antenna/receiver systems: 1) Septentrio Altus APS3G antenna/receiver 2) Trimble NetR8 and Trimble Zephyr Geodetic antenna. | ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"] | ["POINT(0 -89.999)"] | false | false |
Mercer Subglacial Lake (SLM) noble gas and isotopic data
|
1543453 |
2021-12-23 | Gardner, Christopher B.; Lyons, W. Berry |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset includes the following measurements from Niskin casts at Mercer Subglacial Lake as part of the SALSA project: noble gases and their isotopes, d13C-DIC, Ge, 87Sr/86Sr, and 234U/238U | ["POINT(-149.50134 -84.640287)"] | ["POINT(-149.50134 -84.640287)"] | false | false |
Pennell Trough, Ross Sea bathymetry and glacial landforms
|
1246353 1745055 1745043 |
2021-10-04 | Greenwood, Sarah; Munevar Garcia, Santiago; Eareckson, Elizabeth; Anderson, John; Prothro, Lindsay; Simkins, Lauren |
Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. |
Bathymetry from multibeam echo sounding data in Pennell Trough, Ross Sea, Antarctica was collected onboard the RVIB Nathaniel B. Palmer (NBP) 15-02 cruise using a Kongsberg EM122 operating in dual swath mode at 12 kHz frequency with a 1°×1° beam width, swath angular coverage set to 62°×62°, and 30-60% overlap between survey lines. All raw, ping-edited geophysical data collected on NBP15-02 can be accessed using the Marine Geoscience Data System (Cruise DOI: 10.7284/901477). The bathymetry dataset here is gridded at 20-m resolution with a water depth-dependent vertical resolution on the order of decimeters. Two shapefiles are provided for ice-marginal landforms and meltwater landforms observable in the bathymetry data. The purpose of collecting the bathymetry data on cruise NBP15-02 was to better understand the glacial history of the Ross Sea, and the dataset, inclusive of bathymetry data and shapefiles of glacial landforms, from Pennell Trough are used to understand impacts on subglacial channel morphology and organization during the deglaciation of the region following the Last Glacial Maximum. The published dataset was used and analyzed in the article "Topographic controls on channelized meltwater in the subglacial environment" by Simkins, L.M., Greenwood, S.L., Munevar Garcia, S., Eareckson, E.A., Anderson, J.B., and Prothro, L.O, which was published in Geophysical Research Letters in 2021 (DOI: 10.1029/2021GL094678). | ["POLYGON((174 -75,174.4 -75,174.8 -75,175.2 -75,175.6 -75,176 -75,176.4 -75,176.8 -75,177.2 -75,177.6 -75,178 -75,178 -75.2,178 -75.4,178 -75.6,178 -75.8,178 -76,178 -76.2,178 -76.4,178 -76.6,178 -76.8,178 -77,177.6 -77,177.2 -77,176.8 -77,176.4 -77,176 -77,175.6 -77,175.2 -77,174.8 -77,174.4 -77,174 -77,174 -76.8,174 -76.6,174 -76.4,174 -76.2,174 -76,174 -75.8,174 -75.6,174 -75.4,174 -75.2,174 -75))"] | ["POINT(176 -76)"] | false | false |
Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland
|
1543441 1656518 |
2021-09-14 | Bienert, Nicole; Schroeder, Dustin; Siegfried, Matthew; Peters, Sean; MacKie, Emma; Dawson, Eliza; Christoffersen, Poul |
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments |
This dataset includes raw, uncalibrated voltage vs time measurements from a bistatic radar receiver. We also include some processed data including upsampled matched filtered data, GPS receiver position, antenna separation | [] | [] | false | false |
Antarctic Ice Thickness, Slipperiness, and Subglacial Lake Locations
|
None | 2021-08-13 | Stubblefield, Aaron; Kingslake, Jonathan; Siegfried, Matthew; Arthern, Robert | No project link provided | This data set contains (1) ice thickness (H) and basal sliding coefficient (beta) maps for the Antarctic Ice Sheet from Arthern et al. (2015) "Flow speed within the Antarctic ice sheet and its controls inferred from satellite observations", and (2) Antarctic subglacial lake locations and estimated sizes from Siegfried and Fricker (2018) "Thirteen years of subglacial lake activity in Antarctica from multi-mission satellite altimetry". Data are in zarr (thickness and sliding coefficient maps) and ASCII (lake locations and sizes) formats. | ["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 |
ICECAP: Gridded boundary conditions for Little Dome C, Antarctica, and extracted subglacial lake locations
|
1443690 |
2021-07-14 | Young, Duncan A.; Roberts, Jason; Ritz, Catherine; Frezzotti, Massimo; Quartini, Enrica; Cavitte, Marie G. P; Tozer, Carly; Steinhage, Daniel; Urbini, Stefano; Corr, Hugh F. J.; Van Ommen, Tas; Blankenship, Donald D. |
Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP) |
This data set includes compiled and gridded ice thickness, bed elevation, and bed roughness originally published in Young et al., 2017, as well as subglacial lakes identified at the Little Dome C old ice candidate site in Antarctica. | ["POLYGON((118 -74.1,118.9 -74.1,119.8 -74.1,120.7 -74.1,121.6 -74.1,122.5 -74.1,123.4 -74.1,124.3 -74.1,125.2 -74.1,126.1 -74.1,127 -74.1,127 -74.33,127 -74.56,127 -74.79,127 -75.02,127 -75.25,127 -75.48,127 -75.71,127 -75.94,127 -76.17,127 -76.4,126.1 -76.4,125.2 -76.4,124.3 -76.4,123.4 -76.4,122.5 -76.4,121.6 -76.4,120.7 -76.4,119.8 -76.4,118.9 -76.4,118 -76.4,118 -76.17,118 -75.94,118 -75.71,118 -75.48,118 -75.25,118 -75.02,118 -74.79,118 -74.56,118 -74.33,118 -74.1))"] | ["POINT(122.5 -75.25)"] | false | false |
Antarctic Active Subglacial Lake Inventory from ICESat Altimetry
|
0636719 0636970 |
2021-04-21 | Smith, Ben; Joughin, Ian; Tulaczyk, Slawek; Fricker, Helen |
Collaborative Research: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries |
This data set contains lake boundaries, volume changes, and gridded elevations for 124 active subglacial lakes beneath the Antarctic ice sheet. Lakes were identified using laser altimetry data obtained from 2003 to 2009 by NASA's Ice, Cloud, and Land Elevation Satellite (ICESat) mission. The data are provided in Keyhole Markup Language (KML), comma-separated values (CSV), and GEOTiff formats. | ["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 |
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 |
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 |
ICECAP Basal Interface Specularity Content Profiles: IPY and OIB
|
1543452 0733025 1443690 0636724 |
2020-08-24 | Young, Duncan A.; Blankenship, Donald D.; Roberts, Jason; Siegert, Martin; van Ommen, Tas; Greenbaum, Jamin; Schroeder, Dustin |
Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP) East Antarctic Grounding Line Experiment (EAGLE) Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP) |
The International Collaborative Exploration of the Cryosphere though Airborne Profiling (ICECAP) collected five seasons of aerogeophysical data data through the NSFs International Polar Year and NASAs Operation Ice Bridge programs in East Antarctica, using the coherent HiCARS 60 MHz radar system. By comparing echo strengths for different focusing apertures, and accounting for the ranges and angles involved, we can derive the "specularity content" of the bed echo, a proxy for small scale bed roughness and a good indicator for subglacial water pressure in regions of distributed subglacial water (Schroeder et al., 2014, IEEE GRSL, 10.1109/LGRS.2014.2337878; IEEE; Dow et al., 2019, EPSL https://doi.org/10.1016/j.epsl.2019.115961). Specularity data are inherently noisy, so these products have been smoothed with a 1 km filter. | ["POLYGON((80 -65,89 -65,98 -65,107 -65,116 -65,125 -65,134 -65,143 -65,152 -65,161 -65,170 -65,170 -66.5,170 -68,170 -69.5,170 -71,170 -72.5,170 -74,170 -75.5,170 -77,170 -78.5,170 -80,161 -80,152 -80,143 -80,134 -80,125 -80,116 -80,107 -80,98 -80,89 -80,80 -80,80 -78.5,80 -77,80 -75.5,80 -74,80 -72.5,80 -71,80 -69.5,80 -68,80 -66.5,80 -65))"] | ["POINT(125 -72.5)"] | 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 |
Ohio Range Subglacial rock core cosmogenic nuclide data
|
1341658 |
2020-06-28 | Mukhopadhyay, Sujoy |
Constraining Plio-Pleistocene West Antarctic Ice Sheet Behavior from the Ohio Range and Scott Glacier |
The data set consists of cosmogenic berrylium-10 and aluminum-26, along with neon-21, in a set of 4 rock-cores obtained from the Ohio Range, West Antarctica. The rock cores were obtained using the WInkie drill. The depth to the cores varies from 12 meters to 28 meters. The recovered rock cores analyzed for the cosmogenic isotopes varies from 22 cm long to 50 cm long. The data include the following formation: sample details, cosmogenic berrylium-10, aluminum-26 and upper bounds for cosmogenic 21 (since samples have nucleogenic 21) and the step heating data for neon. The data are in Mircrosoft excel format. | ["POLYGON((-116.46 -84.78,-116.452 -84.78,-116.444 -84.78,-116.436 -84.78,-116.428 -84.78,-116.42 -84.78,-116.412 -84.78,-116.404 -84.78,-116.396 -84.78,-116.388 -84.78,-116.38 -84.78,-116.38 -84.781,-116.38 -84.782,-116.38 -84.783,-116.38 -84.784,-116.38 -84.785,-116.38 -84.786,-116.38 -84.787,-116.38 -84.788,-116.38 -84.789,-116.38 -84.79,-116.388 -84.79,-116.396 -84.79,-116.404 -84.79,-116.412 -84.79,-116.42 -84.79,-116.428 -84.79,-116.436 -84.79,-116.444 -84.79,-116.452 -84.79,-116.46 -84.79,-116.46 -84.789,-116.46 -84.788,-116.46 -84.787,-116.46 -84.786,-116.46 -84.785,-116.46 -84.784,-116.46 -84.783,-116.46 -84.782,-116.46 -84.781,-116.46 -84.78))"] | ["POINT(-116.42 -84.785)"] | false | false |
SOAR-Lake Vostok Survey airborne radar data
|
9911617 9978236 |
2020-04-28 | Studinger, Michael S.; Bell, Robin |
Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR) Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work |
Processed IcePenetrating Radar Altimeter Shot Data (version 2) acquired during the SOAR Twin Otter expedition SOAR-LVS (2000) This data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work | ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"] | ["POINT(104.75 -77.25)"] | false | false |
SOAR-Lake Vostok Survey ice thickness data
|
9911617 9978236 |
2020-04-28 | Studinger, Michael S.; Bell, Robin |
Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR) Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work |
Processed IcePenetrating Radar Altimeter Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000) This data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of ASCII format and include Ice LayerThickness data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work | ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"] | ["POINT(104.75 -77.25)"] | false | false |
Processed Ice Penetrating Radar Altimeter Shot Data (SEGY, version 1) from the Gamburtsev Mountains in Antarctica acquired during the GAMBIT Twin Otter expedition AGAP_GAMBIT (2008)
|
0632292 |
2020-04-20 | Bell, Robin |
Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets |
This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica's Gamburtsev Province Project (AGAP). | ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"] | ["POINT(77 -81.25)"] | false | false |
Processed Ice Penetrating Radar Data (jpeg images) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT
|
0632292 |
2020-04-20 | Bell, Robin; Studinger, Michael S. |
Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets |
This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are jpeg images of Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica's Gamburtsev Province Project (AGAP). | ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"] | ["POINT(77 -81.25)"] | false | false |
Processed Ice Penetrating Radar Data (Matlab format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT
|
0632292 |
2020-04-20 | Bell, Robin; Studinger, Michael S. |
Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets |
This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of MATLAB format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica's Gamburtsev Province Project (AGAP). | ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"] | ["POINT(77 -81.25)"] | false | false |
Processed Ice Penetrating Radar Data (Netcdf format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT
|
0632292 |
2020-04-20 | Bell, Robin; Studinger, Michael S. |
Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets |
This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of Netcdf format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica's Gamburtsev Province Project (AGAP). | ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"] | ["POINT(77 -81.25)"] | false | false |
Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set
|
0839059 |
2020-01-17 | Coenen, Jason; Baudoin, Patrick; Warny, Sophie; Askin, Rosemary; Scherer, Reed Paul; Castañeda, Isla |
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 counts of palynomorphs from subglacial and sub-ice shelf tills from beneath the West Antarctic Ice Sheet. In addition to counts the biostratigraphic ranges are presented on separate tabs. | ["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 |
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 |
Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data
|
1341728 |
2019-10-09 | Stone, John |
EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse |
This data set contains measurements of cosmic-ray-produced Be-10 and Al-26 in quartz from the RB-2 core, recovered from bedrock at a depth of 150 m below the West Antarctic Ice Sheet surface in the Pirrit Hills. The core site is located at latitude S81.09948, longitude W85.15694. Core length is approximately 8 meters. Lithology is A-type granite, similar in composition to bedrock exposed on nearby Harter Nunatak and other mountains in the Pirrit Hills (Lee et al. Geosci. J. 16, 421-433). Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory. Chemical processing and purification methods are described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Aluminum isotope ratios were measured at PRIME Lab, Purdue University, relative to the KNSTD-Al-01-5-2 standard, assuming a standard Al-26/Al-27 ratio of 1.818E-12 (KNSTD normalization). Uncertainties are 1-sigma and include full AMS errors and all known sources of laboratory uncertainty. | ["POLYGON((-86.3 -81,-86.17 -81,-86.04 -81,-85.91 -81,-85.78 -81,-85.65 -81,-85.52 -81,-85.39 -81,-85.26 -81,-85.13 -81,-85 -81,-85 -81.03,-85 -81.06,-85 -81.09,-85 -81.12,-85 -81.15,-85 -81.18,-85 -81.21,-85 -81.24,-85 -81.27,-85 -81.3,-85.13 -81.3,-85.26 -81.3,-85.39 -81.3,-85.52 -81.3,-85.65 -81.3,-85.78 -81.3,-85.91 -81.3,-86.04 -81.3,-86.17 -81.3,-86.3 -81.3,-86.3 -81.27,-86.3 -81.24,-86.3 -81.21,-86.3 -81.18,-86.3 -81.15,-86.3 -81.12,-86.3 -81.09,-86.3 -81.06,-86.3 -81.03,-86.3 -81))"] | ["POINT(-85.65 -81.15)"] | false | false |
Antarctic topographic and subglacial lake geostatistical simulations
|
1745137 |
2019-10-02 | MacKie, Emma; Schroeder, Dustin; Caers, Jef; Scheidt, Celine; Siegfried, Matthew |
CAREER: Cross-Instrument Synthesis of Antarctic Radar Sounding Observations |
These data accompany the paper "Antarctic Topographic Realizations and Geostatistical Modeling Used to Map Subglacial Lakes" (MacKie et al., in review). This dataset contains 100 geostatistically generated subglacial topographic realizations for Antarctica. Data science techniques were used to calculate the probability of the occurrence of radar-detected lakes and altimetry-detected (active) lakes across the continent, using each topographic realization as a parameter. This generated 100 probability maps of the likelihood of radar-detected lake occurrence and 100 probability maps of active lake occurrence. Further statistics were used to generate 100 binary maps showing expected radar-detected lake locations. The ensemble of realizations can be used for uncertainty quantification. | ["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 |
Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins
|
1148982 |
2019-07-31 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
The Transantarctic Mountains (TAMs) are the largest non-collisional mountain range on Earth. Their origin, as well as the origin of the Wilkes Subglacial Basin (WSB) along the inland side of the TAMs, have been widely debated, and a key constraint to distinguish between competing models is the underlying crustal structure. Previous investigations have examined this structure but have primarily focused on a small region of the central TAMs near Ross Island, providing little along-strike constraint. In this study, we use data from the new Transantarctic Mountains Northern Network and from five stations operated by the Korea Polar Research Institute to investigate the crustal structure beneath a previously unexplored portion of the TAMs. Using S-wave receiver functions and Rayleigh wave phase velocities, crustal thickness and average crustal shear velocity (Vs) are resolved within ±4 km and ±0.1 km/s, respectively. The crust thickens from ~20 km near the Ross Sea coast to ~46 km beneath the northern TAMs, which is somewhat thicker than that imaged in previous studies beneath the central TAMs. The crust thins to ~41 km beneath the WSB.Vs ranges from ~3.1-3.9 km/s, with slower velocities near the coast. Our findings are consistent with a flexural origin for the TAMs and WSB, where these features result from broad flexure of the East Antarctic lithosphere and uplift along its western edge due to thermal conduction from hotter mantle beneath West Antarctica. Locally thicker crust may explain the ~1 km of additional topography in the northern TAMs compared to the central TAMs. | ["POLYGON((150 -72,152 -72,154 -72,156 -72,158 -72,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,170 -72.3,170 -72.6,170 -72.9,170 -73.2,170 -73.5,170 -73.8,170 -74.1,170 -74.4,170 -74.7,170 -75,168 -75,166 -75,164 -75,162 -75,160 -75,158 -75,156 -75,154 -75,152 -75,150 -75,150 -74.7,150 -74.4,150 -74.1,150 -73.8,150 -73.5,150 -73.2,150 -72.9,150 -72.6,150 -72.3,150 -72))"] | ["POINT(160 -73.5)"] | false | false |
The Geochemistry of englacial brine from Taylor Glacier, Antarctica.
|
1144176 |
2019-05-07 | Lyons, W. Berry; Gardner, Christopher B. |
Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys |
Blood Falls is a hypersaline, iron‐rich discharge at the terminus of the Taylor Glacier in the McMurdo Dry Valleys, Antarctica. In November 2014, brine in a conduit within the glacier was penetrated and sampled using clean‐entry techniques and a thermoelectric melting probe called the IceMole. We analyzed the englacial brine sample for filterable iron (fFe), total Fe, major cations and anions, nutrients, organic carbon, and perchlorate. In addition, aliquots were analyzed for minor and trace elements and isotopes including δD and δ18O of water, δ34S and δ18O of sulfate, 234U, 238U, δ11B, 87Sr/86Sr, and δ81Br. These measurements were made in order to (1) determine the source and geochemical evolution of the brine and (2) compare the chemistry of the brine to that of nearby hypersaline lake waters and previous supraglacially sampled collections of Blood Falls outflow that were interpreted as end‐member brines. | ["POLYGON((162.250099 -77.719928,162.2519358 -77.719928,162.2537726 -77.719928,162.2556094 -77.719928,162.2574462 -77.719928,162.259283 -77.719928,162.2611198 -77.719928,162.2629566 -77.719928,162.2647934 -77.719928,162.2666302 -77.719928,162.268467 -77.719928,162.268467 -77.7201251,162.268467 -77.7203222,162.268467 -77.7205193,162.268467 -77.7207164,162.268467 -77.7209135,162.268467 -77.7211106,162.268467 -77.7213077,162.268467 -77.7215048,162.268467 -77.7217019,162.268467 -77.721899,162.2666302 -77.721899,162.2647934 -77.721899,162.2629566 -77.721899,162.2611198 -77.721899,162.259283 -77.721899,162.2574462 -77.721899,162.2556094 -77.721899,162.2537726 -77.721899,162.2519358 -77.721899,162.250099 -77.721899,162.250099 -77.7217019,162.250099 -77.7215048,162.250099 -77.7213077,162.250099 -77.7211106,162.250099 -77.7209135,162.250099 -77.7207164,162.250099 -77.7205193,162.250099 -77.7203222,162.250099 -77.7201251,162.250099 -77.719928))"] | ["POINT(162.259283 -77.7209135)"] | false | false |
Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line
|
0838947 |
2018-09-09 | Begeman, Carolyn |
Collaborative Research: Integrative Study of Marine Ice Sheet Stability & Subglacial Life Habitats in W Antarctica - Lake & Ice Stream Subglacial Access Research Drilling (LISSARD) |
This dataset contains ice-shelf basal melt rates and vertical strain rates for 11 sites near the Whillans Ice Stream grounding line. These rates were determined using Autonomous Phase-Sensitive Radar. Data processing is described in Begeman et al. 2018, JGR Oceans. These sites are concentrated within an embayment of the Ross Ice Shelf. These melt rates and strain rates were determined over periods ranging from 10 to 38 days in December 2014 to January 2015. | ["POLYGON((-165.28 -84.24,-165.086 -84.24,-164.892 -84.24,-164.698 -84.24,-164.504 -84.24,-164.31 -84.24,-164.116 -84.24,-163.922 -84.24,-163.728 -84.24,-163.534 -84.24,-163.34 -84.24,-163.34 -84.252,-163.34 -84.264,-163.34 -84.276,-163.34 -84.288,-163.34 -84.3,-163.34 -84.312,-163.34 -84.324,-163.34 -84.336,-163.34 -84.348,-163.34 -84.36,-163.534 -84.36,-163.728 -84.36,-163.922 -84.36,-164.116 -84.36,-164.31 -84.36,-164.504 -84.36,-164.698 -84.36,-164.892 -84.36,-165.086 -84.36,-165.28 -84.36,-165.28 -84.348,-165.28 -84.336,-165.28 -84.324,-165.28 -84.312,-165.28 -84.3,-165.28 -84.288,-165.28 -84.276,-165.28 -84.264,-165.28 -84.252,-165.28 -84.24))"] | ["POINT(-164.31 -84.3)"] | false | false |
Supraglacial Lake Depths on McMurdo Ice Shelf, Antarctica
|
1443126 |
2018-09-04 | MacAyeal, Douglas; Banwell, Alison |
Impact of Supraglacial Lakes on Ice-Shelf Stability |
During the melt seasons of 2015/6 and 2016/7, water pressure gages were deployed on the McMurdo Ice Shelf to observe water depth in supraglacial lakes and streams. This was done in support of research directed toward understanding how filling and draining supraglacial lakes would induce ice-shelf flexure and fracture. | ["POLYGON((165.911079 -77.872851,165.941267 -77.872851,165.971455 -77.872851,166.001643 -77.872851,166.031831 -77.872851,166.062019 -77.872851,166.092207 -77.872851,166.122395 -77.872851,166.152583 -77.872851,166.182771 -77.872851,166.212959 -77.872851,166.212959 -77.8781411,166.212959 -77.8834312,166.212959 -77.8887213,166.212959 -77.8940114,166.212959 -77.8993015,166.212959 -77.9045916,166.212959 -77.9098817,166.212959 -77.9151718,166.212959 -77.9204619,166.212959 -77.925752,166.182771 -77.925752,166.152583 -77.925752,166.122395 -77.925752,166.092207 -77.925752,166.062019 -77.925752,166.031831 -77.925752,166.001643 -77.925752,165.971455 -77.925752,165.941267 -77.925752,165.911079 -77.925752,165.911079 -77.9204619,165.911079 -77.9151718,165.911079 -77.9098817,165.911079 -77.9045916,165.911079 -77.8993015,165.911079 -77.8940114,165.911079 -77.8887213,165.911079 -77.8834312,165.911079 -77.8781411,165.911079 -77.872851))"] | ["POINT(166.062019 -77.8993015)"] | false | false |
Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains
|
1148982 |
2017-04-20 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
Using data from the Transantarctic Mountains (TAMs) Northern Network, shear-wave splitting analysis has been employed to constrain azimuthal anisotropy beneath a portion of the northern TAMs. Splitting measurements were made for PKS, SKS, and SKKS phases with the eigenvalue method in SplitLab. The results show two distinct geographic regions of anisotropy: one behind the TAMs front and the other along the Ross Sea coastline. The anisotropic structure behind the TAMs front is best attributed to relict fabric associated with past tectonic episodes. Along the coastline, the anisotropy is interpreted to reflect mantle flow associated with rift-related decompression melting and Cenozoic extension. | ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"] | ["POINT(159.223506 -74.6349495)"] | false | false |
Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains
|
1148982 |
2017-04-20 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
Using data from the Transantarctic Mountains (TAMs) Northern Network, the shear wave velocity structure beneath the northern TAMs was investigated with surface wave tomography. Rayleigh wave phase velocities were calculated using a two-plane wave approximation and were then inverted for shear velocity structure. The resulting model shows a low velocity zone (~4.24 km/s) at ~160 km depth offshore and adjacent to Mt. Melbourne that extends inland and vertically upwards to ~100 km depth beneath the northern TAMs and Victoria Land. Another low velocity zone (~4.16-4.24 km/s) is also seen at ~150 km depth beneath Ross Island, and relatively slow velocities (~4.24-4.32 km/s) along the Terror Rift connect the two low velocity zones. This structure has been interpreted to reflect rift-related decompression melting along the TAMs front, which would provide thermal buoyancy to uplift the mountain range. | ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"] | ["POINT(159.223506 -74.6349495)"] | false | false |
Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography
|
1148982 |
2017-04-06 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
Stretching ~3,500 km across Antarctica, with peak elevations up to 4,500 m, the Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth and represent a tectonic boundary between the East Antarctica (EA) craton and the West Antarctic Rift System. The origin and uplift mechanism associated with the TAMs is controversial, and multiple models have been proposed. Seismic investigations of the TAMs' subsurface structure can provide key constraints to help evaluate these models, but previous studies have been primarily focused only on the central TAMs near Ross Island. Using data from the new 15-station Transantarctic Mountain Northern Network as well as data from several smaller networks, this study investigates the upper mantle velocity structure beneath a previously unexplored portion of the northern TAMs through regional body wave tomography. Relative travel-times were calculated for 11,182 P-wave and 8,285 S-wave arrivals from 790 and 581 Mw ≥ 5.5 events, respectively, using multi-channel cross correlation, and these data were then inverted for models of the upper mantle seismic structure. Resulting P- and S-wave tomography images reveal two focused low velocity anomalies beneath Ross Island (RI; δVP ≈ -2.0%; δVS ≈ -1.5% to -4.0%) and Terra Nova Bay (TNB; δVP ≈ -1.5% to -2.0%; δVS ≈ -1.0% to -4.0%) that extend to depths of ~200 and ~150 km, respectively. The RI and TNB slow anomalies also extend ~50-100 km laterally beneath the TAMs front and sharply abut fast velocities beneath the EA craton (δVP ≈ 0.5% to 2%; δVS ≈ 1.5% to 4.0%). A low velocity region (δVP ≈ -1.5%), centered at ~150 km depth beneath the Terror Rift (TR) and primarily constrained within the Victoria Land Basin, connects the RI and TNB anomalies. The focused low velocities are interpreted as regions of partial melt and buoyancy-driven upwelling, connected by a broad region of slow (presumably warm) upper mantle associated with Cenozoic extension along the TR. Dynamic topography estimates based on the imaged S-wave velocity perturbations are consistent with observed surface topography in the central and northern TAMs, thereby providing support for uplift models that advocate for thermal loading and a flexural origin for the mountain range. | ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"] | ["POINT(159.223506 -74.6349495)"] | false | false |
Magnetic anomaly data over central Marie Byrd Land, West Antarctica (GIMBLE.GMGEO2)
|
1043761 |
2017-02-20 | Young, Duncan A.; Holt, John W.; Blankenship, Donald D. |
Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE) |
GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading "#" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GMGEO2 contains line based data (in ASCII space delimited txt files) relating to magnetic anomaly. The raw data was obtained by a tail mounted Geometrics G-823A magnetometer. No heading correction, cross over correction, continuation or base correction have been applied. Data with significant geomagnetic activity (restricted to 07-Dec-2014 and 23-Dec-2014) were removed. | ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"] | ["POINT(-133 -77.25)"] | false | false |
Gravity disturbance data over central Marie Byrd Land, West Antarctica (GIMBLE.GGCMG2)
|
1043761 |
2017-02-20 | Young, Duncan A.; Holt, John W.; Blankenship, Donald D. |
Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE) |
GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading "#" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GGCMG2 contains line based data relating to gravity disturbance, processed from raw acceleration and position data by propriety software from Gravimetric Technologies and Novatel. The raw data was obtained a Canadian MicroGravity GT-1A gravimeter in ICP5, and a GT-2A gravimeter in ICP6. Data reduction was led by T. Richter. | ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"] | ["POINT(-133 -77.25)"] | false | false |
Ice thickness and related data over central Marie Byrd Land, West Antarctica (GIMBLE.GR2HI2)
|
1043761 |
2017-02-20 | Young, Duncan A.; Holt, John W.; Blankenship, Donald D. |
Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE) |
GIMBLE was proposed as the first systematic aerogeophysical investigation of the subglacial massif underlying central Marie Byrd Land. Aerogeophysically configured Baslers conducted 14 flights from Byrd Surface Camp and WAIS Divide Camp over two field seasons (January 2013 and December 2014). Airborne ice penetrating radar, gravity and magnetics were the primary datasets collected. Level 2 data represent geolocated geophysical properties (e.g ice thickness), derived from Level 1B measurements (e.g. radar echo delay). Dataset structures are based on those used for Operation Ice Bridge, and are line based data in ASCII space delimited .txt files, with a header delimited by leading "#" characters documenting column assignment and metadata. Georefering data is contained in .met files. GIMBLE.GR2HI2 contains line based data (in ASCII space delimited txt files) relating to ice thickness, bed elevation and bed reflectivity, extracted from 1-D focused radargrams by semiautomatic interpretation. Data was acquired using HiCARS2 in ICP5, and MARFA in ICP6. Some data loss occurred in ICP6 (in particular F10,F11, and F14), limiting the lines that were focused. Data reduction was led by D. Young and S. Kempf. | ["POLYGON((-156 -74.5,-151.4 -74.5,-146.8 -74.5,-142.2 -74.5,-137.6 -74.5,-133 -74.5,-128.4 -74.5,-123.8 -74.5,-119.2 -74.5,-114.6 -74.5,-110 -74.5,-110 -75.05,-110 -75.6,-110 -76.15,-110 -76.7,-110 -77.25,-110 -77.8,-110 -78.35,-110 -78.9,-110 -79.45,-110 -80,-114.6 -80,-119.2 -80,-123.8 -80,-128.4 -80,-133 -80,-137.6 -80,-142.2 -80,-146.8 -80,-151.4 -80,-156 -80,-156 -79.45,-156 -78.9,-156 -78.35,-156 -77.8,-156 -77.25,-156 -76.7,-156 -76.15,-156 -75.6,-156 -75.05,-156 -74.5))"] | ["POINT(-133 -77.25)"] | 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 |
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling
|
1142162 |
2016-01-01 | Stone, John |
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling |
This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public. | ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"] | ["POINT(-94.64 -81.755)"] | 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 |
Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone
|
0838855 0838854 |
2014-10-30 | Jacobel, Robert |
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 ground-based, gridded, ice-penetrating radar thickness and basal reflection power, along with GPS coordinates, for two areas of Whillans Ice Stream: Subglacial Lake Whillans and the Whillans Ice Stream grounding zone. | ["POLYGON((-164 -84.2,-163 -84.2,-162 -84.2,-161 -84.2,-160 -84.2,-159 -84.2,-158 -84.2,-157 -84.2,-156 -84.2,-155 -84.2,-154 -84.2,-154 -84.21,-154 -84.22,-154 -84.23,-154 -84.24,-154 -84.25,-154 -84.26,-154 -84.27,-154 -84.28,-154 -84.29,-154 -84.3,-155 -84.3,-156 -84.3,-157 -84.3,-158 -84.3,-159 -84.3,-160 -84.3,-161 -84.3,-162 -84.3,-163 -84.3,-164 -84.3,-164 -84.29,-164 -84.28,-164 -84.27,-164 -84.26,-164 -84.25,-164 -84.24,-164 -84.23,-164 -84.22,-164 -84.21,-164 -84.2))"] | ["POINT(-159 -84.25)"] | false | false |
Interaction of Ice Stream Flow with Heterogeneous Beds
|
0838811 |
2014-04-14 | Sergienko, Olga |
Model Investigation of Ice Stream/Subglacial Lake Systems |
This data set consists of outputs of several numerical models simulating ice stream flow over undulated bed, interaction of ice stream flow, and subglacial and supraglacial hydraulic systems. All simulations are performed for idealized geometries using finite-element models. | ["POINT(0 -78)"] | ["POINT(0 -78)"] | 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 |
Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica
|
0739681 0739698 |
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 |
Subglacial water flow paths under Thwaites Glacier, West Antarctica
|
0636724 |
2012-05-21 | Carter, Sasha P.; Young, Duncan A.; Blankenship, Donald D. |
Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System |
This data set contains subglacial water flow paths beneath Thwaites Glacier, West Antarctica, interpreted from ice thickness and bed elevation measurements collected between 7 December 2004 and 31 January 2005 by the Airborne Geophysical Survey of the Amundsen Embayment (AGASEA) expedition. Data consist of an ASCII text file with geographical coordinates, hydraulic head, and bed and surface elevations, and a corresponding .pdf map. Data are available via FTP. | ["POLYGON((-120 -75,-117 -75,-114 -75,-111 -75,-108 -75,-105 -75,-102 -75,-99 -75,-96 -75,-93 -75,-90 -75,-90 -75.5,-90 -76,-90 -76.5,-90 -77,-90 -77.5,-90 -78,-90 -78.5,-90 -79,-90 -79.5,-90 -80,-93 -80,-96 -80,-99 -80,-102 -80,-105 -80,-108 -80,-111 -80,-114 -80,-117 -80,-120 -80,-120 -79.5,-120 -79,-120 -78.5,-120 -78,-120 -77.5,-120 -77,-120 -76.5,-120 -76,-120 -75.5,-120 -75))"] | ["POINT(-105 -77.5)"] | 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 |
Millennially Averaged Accumulation Rates for Lake Vostok
|
0538674 |
2011-08-01 | Macgregor, Joseph A.; Matsuoka, Kenichi; Studinger, Michael S.; Waddington, Edwin D.; Winebrenner, Dale |
Collaborative Research: Deciphering the Deep Ice and the Ice-water Interface over Lake Vostok Using Existing Radar Data |
This data set consists of inferred accumulation rates from three radar layers (26, 35 and 41 thousand years old) in the Vostok Subglacial Lake region. Accumulation rates were inferred using Local-Layer Approximation (LLA), which assumes that the strain-rate history of a particle traveling through the ice sheet can be approximated by the vertical strain-rate profile at the current position of the particle, which the researchers assume to be uniform. Parameters include location, in latitude and longitude, polar stereographic coordinates, and local grid X and Y coordinates, along with layer age, in thousands of years (ka), and inferred accumulation rate (cm/a). The data cover a 150 by 350 km area. Data are available via FTP, as a text file (.txt) with columns in comma separated value format. | ["POLYGON((68.4 -75.7,69.61 -75.7,70.82 -75.7,72.03 -75.7,73.24 -75.7,74.45 -75.7,75.66 -75.7,76.87 -75.7,78.08 -75.7,79.29 -75.7,80.5 -75.7,80.5 -76.04,80.5 -76.38,80.5 -76.72,80.5 -77.06,80.5 -77.4,80.5 -77.74,80.5 -78.08,80.5 -78.42,80.5 -78.76,80.5 -79.1,79.29 -79.1,78.08 -79.1,76.87 -79.1,75.66 -79.1,74.45 -79.1,73.24 -79.1,72.03 -79.1,70.82 -79.1,69.61 -79.1,68.4 -79.1,68.4 -78.76,68.4 -78.42,68.4 -78.08,68.4 -77.74,68.4 -77.4,68.4 -77.06,68.4 -76.72,68.4 -76.38,68.4 -76.04,68.4 -75.7))"] | ["POINT(74.45 -77.4)"] | 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 |
Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica
|
0338151 |
2010-06-15 | Raymond, Charles; Matsuoka, Kenichi |
Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data |
This data set contains the results of a model study of spatial variations of ice temperature and subglacial conditions using available ice-penetrating radar data around a future deep ice coring site near the Ross and Amundsen flow divide of West Antarctic Ice Sheet. The model data are based on radar data collected by the Support Office of Aerogeophysical Research (SOAR) at the University of Texas, and the University of Washington, in 2000. The data include values for attenuation estimates for individual radar profiles. Data are available via FTP in MATLAB (.mat) and Portable Document (.pdf) formats. | ["POINT(-112.09 -79.47)"] | ["POINT(-112.09 -79.47)"] | false | false |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till
|
0440523 0538195 0424589 |
2010-04-14 | Marone, Chris; Anandakrishnan, Sridhar |
Laboratory Study of Stick-Slip Behavior and Deformation Mechanics of Subglacial Till |
This data set includes the results of laboratory experiments examining the constitutive properties of subglacial till, under dynamic stressing. The data include the results of shear strain and stress experiments. Testing was carried out in a servo-controlled biaxial shear device under controlled temperature and stress conditions, allowing both sliding and microstructural processes to be studied in detail. Till samples were collected from Matanuska, Alaska and from Caesar till at the Laurentide Ice Sheet. The data are available via FTP in ASCII text format (.txt). | ["POINT(-147.753056 61.781667)", "POINT(-83.006944 40.067222)", "POINT(147.758889 61.779444)"] | ["POINT(-147.753056 61.781667)", "POINT(-83.006944 40.067222)", "POINT(147.758889 61.779444)"] | false | false |
Antarctic Subglacial Lake Classification Inventory
|
9319379 9911617 |
2009-02-06 | Blankenship, Donald D.; Holt, John W.; Carter, Sasha P. |
Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR) |
This data set is an Antarctic radar-based subglacial lake classification collection, which focuses on the radar reflection properties of each given lake. The Subglacial lakes are separated into four categories specified by radar reflection properties. Additional information includes: latitude, longitude, length (in kilometers), hydro-potential (in meters), bed elevation (in meters above WGS84), and ice thickness (in meters). Source data used to compile this data set were collected between 1998 and 2001. Data are available via FTP as a Microsoft Excel Spreadsheet (XLS), and Tagged Image File Format (TIF). | ["POLYGON((-160 -70,-142.5 -70,-125 -70,-107.5 -70,-90 -70,-72.5 -70,-55 -70,-37.5 -70,-20 -70,-2.5 -70,15 -70,15 -72,15 -74,15 -76,15 -78,15 -80,15 -82,15 -84,15 -86,15 -88,15 -90,-2.5 -90,-20 -90,-37.5 -90,-55 -90,-72.5 -90,-90 -90,-107.5 -90,-125 -90,-142.5 -90,-160 -90,-160 -88,-160 -86,-160 -84,-160 -82,-160 -80,-160 -78,-160 -76,-160 -74,-160 -72,-160 -70))"] | ["POINT(-72.5 -80)"] | false | false |
Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains
|
0816934 |
2009-01-01 | Thomson, Stuart |
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((65 -66,72.9 -66,80.8 -66,88.7 -66,96.6 -66,104.5 -66,112.4 -66,120.3 -66,128.2 -66,136.1 -66,144 -66,144 -66.3,144 -66.6,144 -66.9,144 -67.2,144 -67.5,144 -67.8,144 -68.1,144 -68.4,144 -68.7,144 -69,136.1 -69,128.2 -69,120.3 -69,112.4 -69,104.5 -69,96.6 -69,88.7 -69,80.8 -69,72.9 -69,65 -69,65 -68.7,65 -68.4,65 -68.1,65 -67.8,65 -67.5,65 -67.2,65 -66.9,65 -66.6,65 -66.3,65 -66))"] | ["POINT(104.5 -67.5)"] | 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 |
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 |
Comprehensive Biological Study of Vostok Accretion Ice
|
0536870 |
2008-01-01 | Rogers, Scott O. |
Comprehensive Biological Study of Vostok Accretion Ice |
The large subglacial Lake Vostok in Antarctica is unique ecological site with a novel microbial biota. The temperatures, pressures and lack of light all select for organisms that may not exist anywhere else on Earth. The accretion ice (lake water frozen to the bottom of the lower surface of the glacier) has preserved microbial samples from each region of Lake Vostok as the glacier passes over and into the lake. Thus, without contaminating the lake with microorganisms from the surface, microbes originating from the lake can be collected, transported to the laboratory and studied. Two of the deepest ice cores sections in this project are part of the international allocation. The will be shared between four researchers (Sergey Bulat from Russia, Jean-Robert Petit and Daniel Prieur from France, Scott Rogers from USA). The United States team will study, isolate, and characterize bacteria, fungi, and viruses that have been sampled from the lake through the process of ice accretion to the lower surface of 3500+m thick glacier overriding the lake. The project will involve a suite of methods, including molecular, morphological, and cultural. This includes observation and description by fluorescence, light, and electron microscopy, isolation on thirteen separate cultural media, polymerase chain reaction amplification, DNA sequencing, and phylogenetic analyses. Eleven accretion ice core sections, as well as two glacial ice core sections. As well as two glacial ice core sections will be studied. The accretion ice core sections, as well as two glacial ice core sections will be studied. The accretion ice core sections represent all of the major regions of the lake that have been sampled by the accretion process in the vicinity of the Vostok 5G ice core. The broader impacts of the work relate to the impact the results will have on the filed. These long=isolated lakes, deep below the Antarctic ice sheet may contain novel uniquely adapted organisms. Glacial ice contains an enormous diversity of entrapped microbes, some of which may be metabolically active in the ice. The microbes from Lake Vostok are of special interest, since they are adapted to cold, dark, and high pressure. Thus, their enzyme systems and biochemical pathways may be significantly different from those in the microbes that are the subject of current studies. As such, these organisms may form compounds that may have useful applications. Also, study of the accretion ice, and eventually the water, from Lake Vostok will provide a basis for the study of other subglacial lakes. Additionally, study of the microbes in the accretion ice will be useful to those planning to study analogous systems on ice-covered planets and moons. | ["POINT(106.8 -72.4667)"] | ["POINT(106.8 -72.4667)"] | false | false |
Subglacial Topography: Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica
|
0230197 |
2006-10-25 | Holt, John W.; Blankenship, Donald D.; Morse, David L.; Vaughan, David G.; Corr, Hugh F. J.; Young, Duncan A. |
Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) |
This data set includes 5 km gridded data from the Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) conducted during the 2004-2005 austral summer. Investigators derived maps of the ice sheet surface and subglacial topography, which covers the entire catchments of both the Thwaites Glacier and the Pine Islands Glacier, from airborne survey systems mounted on a Twin Otter aircraft. The surveys had sufficient density to identify critical ice dynamic transitions within the Amundsen Sea Embayment (ASE). The ASE is the only major drainage to exhibit significant elevation change over the period of available satellite observations. Modeling of the Western Antarctic Ice Sheet (WAIS) deglaciation pinpointed the Pine Island Glacier and the Thwaites Glacier, which comprise a major portion of the ASE, as the most vulnerable features of the WAIS. Present knowledge of the ice thickness and subglacial boundary conditions in the ASE are insufficient to understand its evolution or its sensitivity to climatic change, and it is not yet determined whether these changes are evidence of ongoing deglaciation or simply a fluctuation that does not threaten the equilibrium of the ice sheet. This research will support the efforts of a community of United States and international researchers to assess the present and predict the future behavior of the ice sheet in the ASE. These data are available via FTP. | ["POLYGON((-134.9 -71.7,-129.86 -71.7,-124.82 -71.7,-119.78 -71.7,-114.74 -71.7,-109.7 -71.7,-104.66 -71.7,-99.62 -71.7,-94.58 -71.7,-89.54 -71.7,-84.5 -71.7,-84.5 -72.7,-84.5 -73.7,-84.5 -74.7,-84.5 -75.7,-84.5 -76.7,-84.5 -77.7,-84.5 -78.7,-84.5 -79.7,-84.5 -80.7,-84.5 -81.7,-89.54 -81.7,-94.58 -81.7,-99.62 -81.7,-104.66 -81.7,-109.7 -81.7,-114.74 -81.7,-119.78 -81.7,-124.82 -81.7,-129.86 -81.7,-134.9 -81.7,-134.9 -80.7,-134.9 -79.7,-134.9 -78.7,-134.9 -77.7,-134.9 -76.7,-134.9 -75.7,-134.9 -74.7,-134.9 -73.7,-134.9 -72.7,-134.9 -71.7))"] | ["POINT(-109.7 -76.7)"] | false | false |
Concentration and Isotopic Composition of O2 and N2 in Trapped Gases of the Vostok Ice Core
|
9318121 9222121 |
2002-01-01 | Bender, Michael |
Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test |
These data describe the d18O of O2, d15N of N2, d18Oatm, and O2/N2 ratios of trapped gases in the Vostok ice core from East Antarctica. The investigator used a mass spectrometer to measure gas concentrations and isotopic compositions. Data extend to approximately 420,000 years ago. Two different age models are included. Data are available in tab-delimited ASCII format via ftp. | ["POINT(106.48 -72.28)"] | ["POINT(106.48 -72.28)"] | false | false |