{"dp_type": "Dataset", "free_text": "Geochronology"}
[{"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": "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": "1643868 DeWitt, Regina; 1644197 Simms, Alexander", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "detailed results for rock and sediment OSL ages; De calculation; dose rate calculation, fading, signal measurement", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Joinville Island; Antarctica; Livingston Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Joinville and Livingston Islands - rock and sediment OSL ages", "uid": "601534", "west": -65.0}, {"awards": "1643868 DeWitt, Regina; 1644197 Simms, Alexander", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "raw OSL data for rock and sediment samples collected on Joinville and Livingston Islands", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Joinville Island; Antarctica; Livingston Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "OSL data - Joinville and Livingston Islands - Raw data", "uid": "601532", "west": -65.0}, {"awards": "1644197 Simms, Alexander; 1643868 DeWitt, Regina", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "sediment and rock samples were collected on Joinville and Livingston Islands for OSL dating; feldspar separates were prepared; data set includes Electron microprobe analysis of selected feldspar extracts; includes bmp and tif with elemental maps plus elemental concentrations and Ca:Na:K ratios for feldspar analysis", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Livingston Island; Antarctica; Joinville Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches", "uid": "601531", "west": -65.0}, {"awards": "1443556 Thomson, Stuart", "bounds_geometry": ["POLYGON((-180 -83.5,-178 -83.5,-176 -83.5,-174 -83.5,-172 -83.5,-170 -83.5,-168 -83.5,-166 -83.5,-164 -83.5,-162 -83.5,-160 -83.5,-160 -83.75,-160 -84,-160 -84.25,-160 -84.5,-160 -84.75,-160 -85,-160 -85.25,-160 -85.5,-160 -85.75,-160 -86,-162 -86,-164 -86,-166 -86,-168 -86,-170 -86,-172 -86,-174 -86,-176 -86,-178 -86,180 -86,179 -86,178 -86,177 -86,176 -86,175 -86,174 -86,173 -86,172 -86,171 -86,170 -86,170 -85.75,170 -85.5,170 -85.25,170 -85,170 -84.75,170 -84.5,170 -84.25,170 -84,170 -83.75,170 -83.5,171 -83.5,172 -83.5,173 -83.5,174 -83.5,175 -83.5,176 -83.5,177 -83.5,178 -83.5,179 -83.5,-180 -83.5))"], "date_created": "Tue, 13 Jul 2021 00:00:00 GMT", "description": "List of supplementary tables from publication\r\nHe, J., Thomson, S.N., Reiners, P.W., Hemming, S.R., and Licht, K.J., 2021, Rapid erosion of the central Transantarctic Mountains at the Eocene-Oligocene transition: Evidence from skewed (U-Th)/He date distributions near Beardmore Glacier: Earth and Planetary Science Letters, v. 567, p. 117009, doi:10.1016/j.epsl.2021.117009.\r\n\r\nSupp. Table 1 U-Th/He data\r\nSupp. Table 2 Trace and REE data\r\nSupp. Table 3 Compilation with elevation-weighted resampling\r\nSupp. Table 4 Summary statistics and sampling distribution of large-n samples and compilations.\r\nSupp. Table 5 Perpendicular distance of BAR and CMK sample to Kukri Peneplain\r\nSupp. Table 6 Compilation of apatite He data from east Antarctica used in Fig. 1\r\n", "east": -160.0, "geometry": ["POINT(-175 -84.75)"], "keywords": "Antarctica; Beardmore Glacier; Erosion; Landscape Evolution; Shackleton Glacier; Transantarctic Mountains; (U-Th)/He", "locations": "Antarctica; Transantarctic Mountains; Beardmore Glacier; Shackleton Glacier", "north": -83.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Thomson, Stuart; He, John; Reiners, Peter; Hemming, Sidney R.; Licht, Kathy", "project_titles": "Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis", "projects": [{"proj_uid": "p0010188", "repository": "USAP-DC", "title": "Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Apatite (U-Th)/He and TREE Data Central Transantarctic Mountains", "uid": "601462", "west": 170.0}, {"awards": "1443576 Panter, Kurt", "bounds_geometry": ["POLYGON((-154.1 -86.9,-154.03 -86.9,-153.96 -86.9,-153.89 -86.9,-153.82 -86.9,-153.75 -86.9,-153.68 -86.9,-153.61 -86.9,-153.54 -86.9,-153.47 -86.9,-153.4 -86.9,-153.4 -86.92,-153.4 -86.94,-153.4 -86.96,-153.4 -86.98,-153.4 -87,-153.4 -87.02,-153.4 -87.04,-153.4 -87.06,-153.4 -87.08,-153.4 -87.1,-153.47 -87.1,-153.54 -87.1,-153.61 -87.1,-153.68 -87.1,-153.75 -87.1,-153.82 -87.1,-153.89 -87.1,-153.96 -87.1,-154.03 -87.1,-154.1 -87.1,-154.1 -87.08,-154.1 -87.06,-154.1 -87.04,-154.1 -87.02,-154.1 -87,-154.1 -86.98,-154.1 -86.96,-154.1 -86.94,-154.1 -86.92,-154.1 -86.9))"], "date_created": "Fri, 05 Jun 2020 00:00:00 GMT", "description": "Mt. Early and Sheridan Bluff (87\u00b0S) are the above ice expression of Earth\u2019s southernmost volcanic field that lies approximately 300 km from the South Pole. The dataset supplies the locations and lithological descriptions of the units that the samples were collected from for dating and petrological study. Fundamental compositional information on the mafic volcanic rock samples include whole rock MgO concentrations (wt.%), the forsterite content of olivine and the oxygen isotopic composition of olivine. The dataset also provides a record of what samples have been analyzed for major and trace elements by XRF and ICP-MS, mineral chemistry by EMPA, radiogenic isotopes of Sr, Nd and Pb on whole rock powders by ICP-MS and dating by 40Ar/39Ar method.", "east": -153.4, "geometry": ["POINT(-153.75 -87)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochronology; Glacial Volcanism; Magma Differentiation; Major Elements; Mantle Melting; Solid Earth; Trace Elements; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -86.9, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Panter, Kurt", "project_titles": "Investigating Early Miocene Sub-ice Volcanoes in Antarctica for Improved Modeling and understanding of a Large Magmatic Province", "projects": [{"proj_uid": "p0010105", "repository": "USAP-DC", "title": "Investigating Early Miocene Sub-ice Volcanoes in Antarctica for Improved Modeling and understanding of a Large Magmatic Province"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.1, "title": "Volcanological and Petrological measurements on Mt. Early and Sheridan Bluff volcanoes, upper Scott Glacier, Antarctica ", "uid": "601331", "west": -154.1}, {"awards": "1543256 Shuster, David", "bounds_geometry": ["POLYGON((-66.80688 -67.420674,-66.732895 -67.420674,-66.65891 -67.420674,-66.584925 -67.420674,-66.51094 -67.420674,-66.436955 -67.420674,-66.36297 -67.420674,-66.288985 -67.420674,-66.215 -67.420674,-66.141015 -67.420674,-66.06703 -67.420674,-66.06703 -67.4542151,-66.06703 -67.4877562,-66.06703 -67.5212973,-66.06703 -67.5548384,-66.06703 -67.5883795,-66.06703 -67.6219206,-66.06703 -67.6554617,-66.06703 -67.6890028,-66.06703 -67.7225439,-66.06703 -67.756085,-66.141015 -67.756085,-66.215 -67.756085,-66.288985 -67.756085,-66.36297 -67.756085,-66.436955 -67.756085,-66.51094 -67.756085,-66.584925 -67.756085,-66.65891 -67.756085,-66.732895 -67.756085,-66.80688 -67.756085,-66.80688 -67.7225439,-66.80688 -67.6890028,-66.80688 -67.6554617,-66.80688 -67.6219206,-66.80688 -67.5883795,-66.80688 -67.5548384,-66.80688 -67.5212973,-66.80688 -67.4877562,-66.80688 -67.4542151,-66.80688 -67.420674))"], "date_created": "Thu, 27 Feb 2020 00:00:00 GMT", "description": "This dataset contains 80 detrital and 2 bedrock apatite (U-Th)/He thermochronometric ages from Bourgeois Fjord. Data was collected to constrain timing and patterns of topographic change at Bourgeois Fjord on Ma timescales. Analyses were conducted at the Berkeley Geochronology Center and presented in Microsoft Excel formats.", "east": -66.06703, "geometry": ["POINT(-66.436955 -67.5883795)"], "keywords": "Antarctica; Antarctic Peninsula", "locations": "Antarctic Peninsula; Antarctica", "north": -67.420674, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Clinger, Anna", "project_titles": "Antarctic Peninsula Exhumation and Landscape Development Investigated by Low-Temperature Detrital Thermochronometry", "projects": [{"proj_uid": "p0000876", "repository": "USAP-DC", "title": "Antarctic Peninsula Exhumation and Landscape Development Investigated by Low-Temperature Detrital Thermochronometry"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.756085, "title": "Detrital low-temperature thermochronometry from Bourgeois Fjord, AP", "uid": "601259", "west": -66.80688}, {"awards": "1826712 McMahon, Kelton; 1443386 Emslie, Steven; 1443585 Polito, Michael; 1443424 McMahon, Kelton", "bounds_geometry": ["POLYGON((-59 -62,-58.9 -62,-58.8 -62,-58.7 -62,-58.6 -62,-58.5 -62,-58.4 -62,-58.3 -62,-58.2 -62,-58.1 -62,-58 -62,-58 -62.1,-58 -62.2,-58 -62.3,-58 -62.4,-58 -62.5,-58 -62.6,-58 -62.7,-58 -62.8,-58 -62.9,-58 -63,-58.1 -63,-58.2 -63,-58.3 -63,-58.4 -63,-58.5 -63,-58.6 -63,-58.7 -63,-58.8 -63,-58.9 -63,-59 -63,-59 -62.9,-59 -62.8,-59 -62.7,-59 -62.6,-59 -62.5,-59 -62.4,-59 -62.3,-59 -62.2,-59 -62.1,-59 -62))"], "date_created": "Tue, 24 Sep 2019 00:00:00 GMT", "description": "Radiocarbon dates from pygoscelid penguin tissues from ornithogenic soils and beach deposits at Stranger Point, King George (25 de Mayo) Island, Antarctic Peninsula. Uncorrected dates are in radiocarbon years before present (BP); calibrated dates were corrected for the marine carbon reservoir effect (delta R = 700 +/- 50 years) and calibrated with Calib 7.0.4 to provide 2\u03c3 ranges in calendar years BP. All dates except were completed at the Woods Hole National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility and are designated with OS numbers. Localities include ancient penguin breedings sites (mounds, M), active colonies (I9, B3), and a mid-Holocene marine beach deposit (Pingfo 1).", "east": -58.0, "geometry": ["POINT(-58.5 -62.5)"], "keywords": "Abandoned Colonies; Antarctica; Antarctic Peninsula; Beach Deposit; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Holocene; Penguin; Radiocarbon; Radiocarbon Dates; Snow/ice; Snow/Ice; Stranger Point", "locations": "Stranger Point; Antarctic Peninsula; Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -63.0, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "uid": "601212", "west": -59.0}, {"awards": "1443680 Smith, Craig", "bounds_geometry": ["POLYGON((-65.561 -64.6538,-65.2471 -64.6538,-64.9332 -64.6538,-64.6193 -64.6538,-64.3054 -64.6538,-63.9915 -64.6538,-63.6776 -64.6538,-63.3637 -64.6538,-63.0498 -64.6538,-62.7359 -64.6538,-62.422 -64.6538,-62.422 -64.67842,-62.422 -64.70304,-62.422 -64.72766,-62.422 -64.75228,-62.422 -64.7769,-62.422 -64.80152,-62.422 -64.82614,-62.422 -64.85076,-62.422 -64.87538,-62.422 -64.9,-62.7359 -64.9,-63.0498 -64.9,-63.3637 -64.9,-63.6776 -64.9,-63.9915 -64.9,-64.3054 -64.9,-64.6193 -64.9,-64.9332 -64.9,-65.2471 -64.9,-65.561 -64.9,-65.561 -64.87538,-65.561 -64.85076,-65.561 -64.82614,-65.561 -64.80152,-65.561 -64.7769,-65.561 -64.75228,-65.561 -64.72766,-65.561 -64.70304,-65.561 -64.67842,-65.561 -64.6538))"], "date_created": "Tue, 16 Jul 2019 00:00:00 GMT", "description": "This dataset includes Pb-210 activities, grain-size distributions, and x-radiograph negatives for cores collected primarily during NBP1603 (and also LMG1510) as part of the FjordEco project in Andvord Bay and surrounding areas (Gerlache Strait, and Station B on the shelf). Data are from subsampled intervals of kasten cores and box cores, as well as one megacore. Samples were x-rayed, sliced, and bagged onboard the vessel. Grain-size and Pb-210 analyses were completed in the Sediment Dynamics Lab within the University of Washington School of Oceanography (PI C. Nittrouer).", "east": -62.422, "geometry": ["POINT(-63.9915 -64.7769)"], "keywords": "Antarctica; Geochronology; Grain Size; LMG1510; NBP1603; Sediment; Sediment Core Data", "locations": "Antarctica", "north": -64.6538, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Eidam, Emily; Nittrouer, Charles; Homolka, Khadijah; Smith, Craig", "project_titles": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "projects": [{"proj_uid": "p0010010", "repository": "USAP-DC", "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.9, "title": "Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)", "uid": "601193", "west": -65.561}, {"awards": "1543031 Ivany, Linda", "bounds_geometry": ["POLYGON((-57 -64,-56.9 -64,-56.8 -64,-56.7 -64,-56.6 -64,-56.5 -64,-56.4 -64,-56.3 -64,-56.2 -64,-56.1 -64,-56 -64,-56 -64.05,-56 -64.1,-56 -64.15,-56 -64.2,-56 -64.25,-56 -64.3,-56 -64.35,-56 -64.4,-56 -64.45,-56 -64.5,-56.1 -64.5,-56.2 -64.5,-56.3 -64.5,-56.4 -64.5,-56.5 -64.5,-56.6 -64.5,-56.7 -64.5,-56.8 -64.5,-56.9 -64.5,-57 -64.5,-57 -64.45,-57 -64.4,-57 -64.35,-57 -64.3,-57 -64.25,-57 -64.2,-57 -64.15,-57 -64.1,-57 -64.05,-57 -64))"], "date_created": "Mon, 22 Apr 2019 00:00:00 GMT", "description": "Serially-sampled high-resolution organic carbon isotope data from middle Eocene (~42 Ma) driftwood preserved within the La Meseta Formation, Seymour Island, Antarctica.", "east": -56.0, "geometry": ["POINT(-56.5 -64.25)"], "keywords": "Antarctica; Carbon Isotopes; Driftwood; Eocene; Geochemistry; Geochronology; Isotope Data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Organic Carbon Isotopes; Seasonality; Seymour Island; Wood", "locations": "La Meseta Formation; Antarctica; Seymour Island", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Judd, Emily", "project_titles": "Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica", "projects": [{"proj_uid": "p0010025", "repository": "USAP-DC", "title": "Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.5, "title": "Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour Island, Antarctica", "uid": "601173", "west": -57.0}, {"awards": "1341729 Kirschvink, Joseph", "bounds_geometry": ["POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))"], "date_created": "Fri, 27 Apr 2018 00:00:00 GMT", "description": "", "east": -56.2, "geometry": ["POINT(-57.55 -64.1)"], "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; Glaciology; James Ross Basin; Marine Geoscience; Marine Sediments", "locations": "Antarctica; James Ross Basin", "north": -63.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Skinner, Steven; Kirschvink, Joseph", "project_titles": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica", "projects": [{"proj_uid": "p0000276", "repository": "USAP-DC", "title": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.7, "title": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica", "uid": "601094", "west": -58.9}, {"awards": "1246353 Anderson, John", "bounds_geometry": ["POLYGON((-180 -74.37,-178.85 -74.37,-177.7 -74.37,-176.55 -74.37,-175.4 -74.37,-174.25 -74.37,-173.1 -74.37,-171.95 -74.37,-170.8 -74.37,-169.65 -74.37,-168.5 -74.37,-168.5 -74.747,-168.5 -75.124,-168.5 -75.501,-168.5 -75.878,-168.5 -76.255,-168.5 -76.632,-168.5 -77.009,-168.5 -77.386,-168.5 -77.763,-168.5 -78.14,-169.65 -78.14,-170.8 -78.14,-171.95 -78.14,-173.1 -78.14,-174.25 -78.14,-175.4 -78.14,-176.55 -78.14,-177.7 -78.14,-178.85 -78.14,180 -78.14,178.48 -78.14,176.96 -78.14,175.44 -78.14,173.92 -78.14,172.4 -78.14,170.88 -78.14,169.36 -78.14,167.84 -78.14,166.32 -78.14,164.8 -78.14,164.8 -77.763,164.8 -77.386,164.8 -77.009,164.8 -76.632,164.8 -76.255,164.8 -75.878,164.8 -75.501,164.8 -75.124,164.8 -74.747,164.8 -74.37,166.32 -74.37,167.84 -74.37,169.36 -74.37,170.88 -74.37,172.4 -74.37,173.92 -74.37,175.44 -74.37,176.96 -74.37,178.48 -74.37,-180 -74.37))"], "date_created": "Mon, 05 Feb 2018 00:00:00 GMT", "description": "Dataset includes details of cores collected as part of cruise NBP1502A, a list of radiocarbon-dated samples and samples to be radiocarbon-dated, and grain-size data from select NBP1502A cores.", "east": -168.5, "geometry": ["POINT(178.15 -76.255)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochronology; Marine Geoscience; Marine Sediments; NBP1502; R/v Nathaniel B. Palmer; Sediment Core", "locations": "Antarctica", "north": -74.37, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Simkins, Lauren; Anderson, John; Prothro, Lindsay", "project_titles": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum.", "projects": [{"proj_uid": "p0000395", "repository": "USAP-DC", "title": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.14, "title": "NBP1502A Cruise Core Data", "uid": "601083", "west": 164.8}, {"awards": "1246170 Hall, Brenda", "bounds_geometry": ["POLYGON((155.4 -79.8,155.54 -79.8,155.68 -79.8,155.82 -79.8,155.96 -79.8,156.1 -79.8,156.24 -79.8,156.38 -79.8,156.52 -79.8,156.66 -79.8,156.8 -79.8,156.8 -79.82,156.8 -79.84,156.8 -79.86,156.8 -79.88,156.8 -79.9,156.8 -79.92,156.8 -79.94,156.8 -79.96,156.8 -79.98,156.8 -80,156.66 -80,156.52 -80,156.38 -80,156.24 -80,156.1 -80,155.96 -80,155.82 -80,155.68 -80,155.54 -80,155.4 -80,155.4 -79.98,155.4 -79.96,155.4 -79.94,155.4 -79.92,155.4 -79.9,155.4 -79.88,155.4 -79.86,155.4 -79.84,155.4 -79.82,155.4 -79.8))"], "date_created": "Mon, 23 Oct 2017 00:00:00 GMT", "description": "Hatherton Glacier Radiocarbon Data", "east": 156.8, "geometry": ["POINT(156.1 -79.9)"], "keywords": "Antarctica; Geochronology; Hatherton Glacier; Radiocarbon; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "locations": "Transantarctic Mountains; Hatherton Glacier; Antarctica", "north": -79.8, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hall, Brenda", "project_titles": "Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier", "projects": [{"proj_uid": "p0000304", "repository": "USAP-DC", "title": "Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Hatherton Glacier Radiocarbon Data", "uid": "601063", "west": 155.4}, {"awards": "1142007 Kurbatov, Andrei; 1142069 Dunbar, Nelia", "bounds_geometry": ["POLYGON((0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,216 -60,252 -60,288 -60,324 -60,360 -60,360 -63,360 -66,360 -69,360 -72,360 -75,360 -78,360 -81,360 -84,360 -87,360 -90,324 -90,288 -90,252 -90,216 -90,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,0 -87,0 -84,0 -81,0 -78,0 -75,0 -72,0 -69,0 -66,0 -63,0 -60))"], "date_created": "Wed, 13 Sep 2017 00:00:00 GMT", "description": "This collaborative interdisciplinary research project aims to consolidate, into a single user-friendly database, information about volcanic products detected in Antarctica. By consolidating information about volcanic sources, and physical and geochemical characteristics of volcanic products, this systematic data collection approach will improve the ability of researchers to identify volcanic ash, or tephra, from specific volcanic eruptions that may be spread over large areas in a geologically instantaneous amount of time. AntT database is designed to assist in the identification and cross-correlation of time intervals in various paleoclimate archives that contain volcanic layers from often unknown sources.", "east": 360.0, "geometry": ["POINT(180 -75)"], "keywords": "Antarctica; Geochemistry; Geochronology; Glaciology; Intracontinental Magmatism; IntraContinental Magmatism; Sample/collection Description; Sample/Collection Description; Tephra", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Kurbatov, Andrei V.; Dunbar, Nelia", "project_titles": "Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT)", "projects": [{"proj_uid": "p0000328", "repository": "USAP-DC", "title": "Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Antarctic Tephra Data Base AntT static web site ", "uid": "601052", "west": 0.0}, {"awards": "1142007 Kurbatov, Andrei", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 03 Aug 2017 00:00:00 GMT", "description": "This dataset contains ice core tephra geochemical data from 5 temporal intervals in the RICE, WDC-06A, SPRESSO, and SPICE ice cores. The temporal intervals included are 1991 C.E., 1963 C.E., 1815 C.E., 1809 C.E., and 1257 C.E. These intervals are often analyzed for volcanic sulfate by ice core scientists. The volcanic events associated with these intervals caused global weather and climate phenomena and are often used by climate modelers as well to understand volcanic sulfate loading on the climate.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Intracontinental Magmatism; IntraContinental Magmatism; Tephra", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Kurbatov, Andrei V.", "project_titles": "Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT)", "projects": [{"proj_uid": "p0000328", "repository": "USAP-DC", "title": "Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Antarctic Ice Core Tephra Analysis", "uid": "601038", "west": -180.0}, {"awards": "0636740 Kreutz, Karl", "bounds_geometry": ["POINT(-112.086 -79.468)"], "date_created": "Tue, 11 Jul 2017 00:00:00 GMT", "description": "We present several related datasets from a 2012 snow pit and a 2013 firn core collected near the WAIS Divide field camp in West Antarctica. The data include soluble ions (sodium and non-sea-salt sulfate) and dust particle concentrations, as well as major oxide geochemistry of tephra grains isolated from snow samples. Based on these data, we found evidence of deposition from the 2011 Puyehue Cordon-Caulle (Chile) volcanic eruption at WAIS Divide.", "east": -112.086, "geometry": ["POINT(-112.086 -79.468)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Intracontinental Magmatism; IntraContinental Magmatism; Snow Pit; Tephra; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.468, "nsf_funding_programs": null, "persons": "Koffman, Bess; Kreutz, Karl", "project_titles": "Collaborative Research: Microparticle/tephra analysis of the WAIS Divide ice core", "projects": [{"proj_uid": "p0000040", "repository": "USAP-DC", "title": "Collaborative Research: Microparticle/tephra analysis of the WAIS Divide ice core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.468, "title": "Snowpit evidence of the 2011 Puyehue-Cordon Caulle (Chile) eruption in West Antarctica", "uid": "601036", "west": -112.086}, {"awards": "0944197 Waddington, Edwin", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Tue, 28 Mar 2017 00:00:00 GMT", "description": "The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ~68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8-31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age-ice age difference (Delta age) using a combination of firn densification modeling, ice-flow modeling, and a data set of d15N-N2, a proxy for past firn column thickness. The largest Delta age at WD occurs during the Last Glacial Maximum, and is 525 +/- 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard-Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Delta age at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the \\\"bipolar seesaw\\\".\n\nWe present the WD2014 chronology for the upper part (0-2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of 10Be from WAIS Divide and 14C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5% of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1% of the age at three abrupt climate change events between 27 and 31ka. WD2014 has consistently younger ages than Greenland ice core chronologies during most of the Holocene. For the Younger Dryas-Preboreal transition (11.595 ka; 24 years younger) and the Bolling-Allerod Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity, atmospheric mineral dust, and atmospheric methane concentrations.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Depth-Age-Model; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.481, "nsf_funding_programs": null, "persons": "Fudge, T. J.", "project_titles": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core", "projects": [{"proj_uid": "p0000026", "repository": "USAP-DC", "title": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)", "uid": "601015", "west": -112.1115}, {"awards": "0538427 McConnell, Joseph", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Tue, 28 Mar 2017 00:00:00 GMT", "description": "A state-of-the-art continuous ice core analytical system was used to analyze samples from 0 to ~130 m depth of the recently collected intermediate core WDC05Q from West Antarctica. Interpretation of these records and publication of findings is ongoing.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Depth-Age-Model; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.481, "nsf_funding_programs": null, "persons": "McConnell, Joseph", "project_titles": "Trace and Ultra-Trace Chemistry Measurements of the WAIS Divide Ice Core", "projects": [{"proj_uid": "p0000148", "repository": "USAP-DC", "title": "Trace and Ultra-Trace Chemistry Measurements of the WAIS Divide Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "WAIS Divide Ice-Core Chronology from Intermediate Core WDC05Q", "uid": "601013", "west": -112.1115}, {"awards": "0636964 Welten, Kees", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Wed, 14 Dec 2016 00:00:00 GMT", "description": null, "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Cosmogenic Radionuclides; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrothermal Vent; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.481, "nsf_funding_programs": null, "persons": "Welten, Kees", "project_titles": "Collaborative Research: Cosmogenic Radionuclides in the Deep WAIS Divide Core", "projects": [{"proj_uid": "p0000103", "repository": "USAP-DC", "title": "Collaborative Research: Cosmogenic Radionuclides in the Deep WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Cosmogenic Radionuclides in the WAIS Divide Ice Core", "uid": "600383", "west": -112.1115}, {"awards": "1043554 Willenbring, Jane", "bounds_geometry": ["POINT(161.5 -77.5)"], "date_created": "Wed, 09 Nov 2016 00:00:00 GMT", "description": "The PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events.\nThis study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K-12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete.", "east": 161.5, "geometry": ["POINT(161.5 -77.5)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic Radionuclides; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Isotope; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -77.5, "nsf_funding_programs": null, "persons": "Willenbring, Jane", "project_titles": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "projects": [{"proj_uid": "p0000429", "repository": "USAP-DC", "title": "Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins", "uid": "600379", "west": 161.5}, {"awards": "0229314 Stone, John", "bounds_geometry": ["POLYGON((-136.32 -85.38,-135.136 -85.38,-133.952 -85.38,-132.768 -85.38,-131.584 -85.38,-130.4 -85.38,-129.216 -85.38,-128.032 -85.38,-126.848 -85.38,-125.664 -85.38,-124.48 -85.38,-124.48 -85.493,-124.48 -85.606,-124.48 -85.719,-124.48 -85.832,-124.48 -85.945,-124.48 -86.058,-124.48 -86.171,-124.48 -86.284,-124.48 -86.397,-124.48 -86.51,-125.664 -86.51,-126.848 -86.51,-128.032 -86.51,-129.216 -86.51,-130.4 -86.51,-131.584 -86.51,-132.768 -86.51,-133.952 -86.51,-135.136 -86.51,-136.32 -86.51,-136.32 -86.397,-136.32 -86.284,-136.32 -86.171,-136.32 -86.058,-136.32 -85.945,-136.32 -85.832,-136.32 -85.719,-136.32 -85.606,-136.32 -85.493,-136.32 -85.38))"], "date_created": "Mon, 30 Mar 2015 00:00:00 GMT", "description": "This data set contains site, sample, and analytical data from which to calculate cosmogenic nuclide-based exposure ages for glacial deposits adjacent to Reedy Glacier, Antarctica. The data are formatted as input for the CRONUS online exposure-age calculator (http://www.hess.ess.edu/), which determines the exposure age from the cosmogenic Beryllium-10 and Aluminum-26 production rates.", "east": -124.48, "geometry": ["POINT(-130.4 -85.945)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmogenic; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Reedy Glacier; Sample/collection Description; Sample/Collection Description", "locations": "Reedy Glacier; Antarctica", "north": -85.38, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Stone, John", "project_titles": "Collaborative Research: Late Quaternary History of Reedy Glacier", "projects": [{"proj_uid": "p0000029", "repository": "USAP-DC", "title": "Collaborative Research: Late Quaternary History of Reedy Glacier"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.51, "title": "Reedy Glacier Exposure Ages, Antarctica", "uid": "609601", "west": -136.32}, {"awards": "0739575 Emslie, Steven", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor\u0027s theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information.\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Geochronology; Global; Penguin; Ross Sea; Sample/collection Description; Sample/Collection Description; Scotia Sea; Southern Ocean", "locations": "Antarctic Peninsula; Antarctica; Scotia Sea; Ross Sea; Global; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Patterson, William; Polito, Michael; Emslie, Steven D.", "project_titles": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "projects": [{"proj_uid": "p0000317", "repository": "USAP-DC", "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "uid": "600145", "west": -180.0}, {"awards": "1142156 Marschall, Horst", "bounds_geometry": ["POLYGON((-6.44 -71.93,-5.378 -71.93,-4.316 -71.93,-3.254 -71.93,-2.192 -71.93,-1.13 -71.93,-0.068 -71.93,0.994 -71.93,2.056 -71.93,3.118 -71.93,4.18 -71.93,4.18 -71.998,4.18 -72.066,4.18 -72.134,4.18 -72.202,4.18 -72.27,4.18 -72.338,4.18 -72.406,4.18 -72.474,4.18 -72.542,4.18 -72.61,3.118 -72.61,2.056 -72.61,0.994 -72.61,-0.068 -72.61,-1.13 -72.61,-2.192 -72.61,-3.254 -72.61,-4.316 -72.61,-5.378 -72.61,-6.44 -72.61,-6.44 -72.542,-6.44 -72.474,-6.44 -72.406,-6.44 -72.338,-6.44 -72.27,-6.44 -72.202,-6.44 -72.134,-6.44 -72.066,-6.44 -71.998,-6.44 -71.93))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth\u0027s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica.\n\nDronning Maud Land (DML) occupied a central location during the formation of supercontinents - large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth\u0027s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007-2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.\n", "east": 4.18, "geometry": ["POINT(-1.13 -72.27)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Dronning Maud Land; Geochemistry; Geochronology; Solid Earth", "locations": "Dronning Maud Land; Antarctica", "north": -71.93, "nsf_funding_programs": null, "persons": "Marschall, Horst", "project_titles": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica", "projects": [{"proj_uid": "p0000448", "repository": "USAP-DC", "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.61, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "uid": "600135", "west": -6.44}, {"awards": "0944764 Brook, Edward J.", "bounds_geometry": ["POINT(-148.82 -81.66)"], "date_created": "Wed, 25 Jun 2014 00:00:00 GMT", "description": "This data set provides a new CO2 record from the Siple Dome ice core, Antarctica, that covers 7.4-9.0 ka (thousand years) with 8- to 16-year resolution. A small, about 1-2 ppm, increase of atmospheric CO2 during the 8.2 ka event was observed. The increase is not significant when compared to other centennial variations in the Holocene that are not linked to large temperature changes. The results do not agree with leaf stomata records that suggest a CO2 decrease of up to ~25 ppm and imply that the sensitivity of atmospheric CO2 to the primarily northern hemisphere cooling of the 8.2 ka event was limited.", "east": -148.82, "geometry": ["POINT(-148.82 -81.66)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "locations": "Antarctica; South Pole; Siple Dome", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.; Ahn, Jinho", "project_titles": "Atmospheric CO2 and Abrupt Climate Change", "projects": [{"proj_uid": "p0000179", "repository": "USAP-DC", "title": "Atmospheric CO2 and Abrupt Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.66, "title": "High-resolution Atmospheric CO2 during 7.4-9.0 ka", "uid": "609527", "west": -148.82}, {"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": "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": "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": "0902957 Robinson, Laura", "bounds_geometry": ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project\u0027s goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth\u0027s system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.", "east": -35.0, "geometry": ["POINT(-52.75 -58)"], "keywords": "Biota; Corals; Drake Passage; Geochronology; NBP0805; Oceans; Paleoclimate; Radiocarbon; Southern Ocean", "locations": "Drake Passage; Southern Ocean", "north": -54.5, "nsf_funding_programs": null, "persons": "Robinson, Laura", "project_titles": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "projects": [{"proj_uid": "p0000519", "repository": "USAP-DC", "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.5, "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "uid": "600111", "west": -70.5}, {"awards": "0634619 Hammer, William", "bounds_geometry": ["POINT(166 -84)"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "This award supports preparation and study of fossil dinosaurs discovered on Mt. Kirkpatrick, Antarctica, during the 2003-04 field season. The 4,000 pounds of bone bearing matrix to be processed includes new pieces of Cryolophosaurus, a 22 foot long meat eating theropod, as well as a new unnamed sauropod dinosaur and other yet to be identified taxa. This project advances our understanding of dinosaur evolution and adaptation at the beginning of the reign of the dinosaurs, the Late Triassic and Early Jurassic. This period is poorly understood due to lack of fossils, which makes these fossils from Antarctica particularly unique. Also, since these fossils are from high paleolatitudes they will contribute to our understanding of past climates and the physiologic adaptations of dinosaurs to lengthy periods of darkness. The broader impacts include outreach to the general public through museum exhibits and presentations.", "east": 166.0, "geometry": ["POINT(166 -84)"], "keywords": "Antarctica; Beardmore Glacier; Biota; Geochronology; Solid Earth", "locations": "Antarctica; Beardmore Glacier", "north": -84.0, "nsf_funding_programs": null, "persons": "Hammer, William R.", "project_titles": "Continued Research on the Jurassic Vertebrate Fauna from the Beardmore Glacier Region of Antarctica", "projects": [{"proj_uid": "p0000538", "repository": "USAP-DC", "title": "Continued Research on the Jurassic Vertebrate Fauna from the Beardmore Glacier Region of Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.0, "title": "Continued Research on the Jurassic Vertebrate Fauna from the Beardmore Glacier Region of Antarctica", "uid": "600062", "west": 166.0}, {"awards": "0538580 Hemming, Sidney", "bounds_geometry": ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "This project studies sediment from the ocean floor to understand Antarctica\u0027s geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work\u0027s central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry.", "east": 180.0, "geometry": ["POINT(120 -65)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Geochronology; Isotope Data; Marine Sediments; Oceans; Prydz Bay; Solid Earth; Southern Ocean; Weddell Sea; Wilkes Land", "locations": "Prydz Bay; Weddell Sea; Southern Ocean; Antarctica; Wilkes Land", "north": -60.0, "nsf_funding_programs": null, "persons": "van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R.", "project_titles": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "projects": [{"proj_uid": "p0000524", "repository": "USAP-DC", "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "uid": "600056", "west": 60.0}, {"awards": "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": "0228842 Grew, Edward", "bounds_geometry": ["POLYGON((76 -69.3,76.05 -69.3,76.1 -69.3,76.15 -69.3,76.2 -69.3,76.25 -69.3,76.3 -69.3,76.35 -69.3,76.4 -69.3,76.45 -69.3,76.5 -69.3,76.5 -69.32,76.5 -69.34,76.5 -69.36,76.5 -69.38,76.5 -69.4,76.5 -69.42,76.5 -69.44,76.5 -69.46,76.5 -69.48,76.5 -69.5,76.45 -69.5,76.4 -69.5,76.35 -69.5,76.3 -69.5,76.25 -69.5,76.2 -69.5,76.15 -69.5,76.1 -69.5,76.05 -69.5,76 -69.5,76 -69.48,76 -69.46,76 -69.44,76 -69.42,76 -69.4,76 -69.38,76 -69.36,76 -69.34,76 -69.32,76 -69.3))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts per million in rocks subjected to conditions of the middle and lower crust, that is, temperatures of 700 degrees C or more in the granulite-facies, which is characterized by very low water activities at pressures of 5 to 10 kbar (18-35 km burial). Devolatization reactions with loss of aqueous fluid and partial melting with removal of melt have been cited as primary causes for boron depletion under granulite-facies conditions. Despite the pervasiveness of both these processes, rocks rich in boron are locally found in the granulite-facies, that is, there are mechanisms for retaining boron during the metamorphic process. The Larsemann Hills, Prydz Bay, Antarctica, are a prime example. More than 20 lenses and layered bodies containing four borosilicate mineral species crop out over a 50 square kilometer area, which thus would be well suited for research on boron-rich granulite-facies metamorphic rocks. While most investigators have focused on the causes for loss of boron, this work will investigate how boron is retained during high-grade metamorphism. Field observations and mapping in the Larsemann Hills, chemical analyses of minerals and their host rocks, and microprobe age dating will be used to identify possible precursors and deduce how the precursor materials recrystallized into borosilicate rocks under granulite-facies conditions. \n\nThe working hypothesis is that high initial boron content facilitates retention of boron during metamorphism because above a certain threshold boron content, a mechanism \u0027kicks in\u0027 that facilitates retention of boron in metamorphosed rocks. For example, in a rock with large amounts of the borosilicate tourmaline, such as stratabound tourmalinite, the breakdown of tourmaline to melt could result in the formation of prismatine and grandidierite, two borosilicates found in the Larsemann Hills. This situation is rarely observed in rocks with modest boron content, in which breakdown of tourmaline releases boron into partial melts, which in turn remove boron when they leave the system. Stratabound tourmalinite is associated with manganese-rich quartzite, phosphorus-rich rocks and sulfide concentrations that could be diagnostic for recognizing a tourmalinite protolith in a highly metamorphosed complex where sedimentary features have been destroyed by deformation. Because partial melting plays an important role in the fate of boron during metamorphism, our field and laboratory research will focus on the relationship between the borosilicate units, granite pegmatites and other granitic intrusives. The results of our study will provide information on cycling of boron at deeper levels in the Earth\u0027s crust and on possible sources of boron for granites originating from deep-seated rocks. An undergraduate student will participate in the electron microprobe age-dating of monazite and xenotime as part of a senior project, thereby integrating the proposed research into the educational mission of the University of Maine. In response to a proposal for fieldwork, the Australian Antarctic Division, which maintains Davis station near the Larsemann Hills, has indicated that they will support the Antarctic fieldwork.", "east": 76.5, "geometry": ["POINT(76.25 -69.4)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Geochronology; Solid Earth", "locations": "Antarctica", "north": -69.3, "nsf_funding_programs": null, "persons": "Grew, Edward", "project_titles": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "projects": [{"proj_uid": "p0000431", "repository": "USAP-DC", "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.5, "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "uid": "600030", "west": 76.0}, {"awards": "0125098 Emslie, Steven", "bounds_geometry": ["POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. \n\nOther data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC.", "east": 160.0, "geometry": ["POINT(55 -75)"], "keywords": "Antarctica; Biota; Geochronology; Oceans; Paleoclimate; Penguin; Radiocarbon; Ross Sea; Southern Ocean", "locations": "Southern Ocean; Antarctica; Ross Sea", "north": -60.0, "nsf_funding_programs": null, "persons": "Emslie, Steven D.", "project_titles": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "projects": [{"proj_uid": "p0000220", "repository": "USAP-DC", "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "uid": "600028", "west": -50.0}, {"awards": "0739496 Miller, Molly", "bounds_geometry": ["POLYGON((163.41667 -77.33333,163.46667 -77.33333,163.51667 -77.33333,163.56667 -77.33333,163.61667 -77.33333,163.66667 -77.33333,163.71667 -77.33333,163.76667 -77.33333,163.81667 -77.33333,163.86667 -77.33333,163.91667 -77.33333,163.91667 -77.369997,163.91667 -77.406664,163.91667 -77.443331,163.91667 -77.479998,163.91667 -77.516665,163.91667 -77.553332,163.91667 -77.589999,163.91667 -77.626666,163.91667 -77.663333,163.91667 -77.7,163.86667 -77.7,163.81667 -77.7,163.76667 -77.7,163.71667 -77.7,163.66667 -77.7,163.61667 -77.7,163.56667 -77.7,163.51667 -77.7,163.46667 -77.7,163.41667 -77.7,163.41667 -77.663333,163.41667 -77.626666,163.41667 -77.589999,163.41667 -77.553332,163.41667 -77.516665,163.41667 -77.479998,163.41667 -77.443331,163.41667 -77.406664,163.41667 -77.369997,163.41667 -77.33333))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project answers a simple question: why are there so few fossils in sediment cores from Antarctica\u0027s continental shelf? Antarctica\u0027s benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change.", "east": 163.91667, "geometry": ["POINT(163.66667 -77.516665)"], "keywords": "Biota; Geochronology; Marine Sediments; Oceans; Southern Ocean", "locations": "Southern Ocean", "north": -77.33333, "nsf_funding_programs": null, "persons": "Furbish, David; Miller, Molly", "project_titles": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "projects": [{"proj_uid": "p0000203", "repository": "USAP-DC", "title": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.7, "title": "Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "uid": "600076", "west": 163.41667}, {"awards": "0739693 Ashworth, Allan", "bounds_geometry": ["POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia. In terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica\u0027s ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise.", "east": 162.0, "geometry": ["POINT(161 -77.5)"], "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; GPS; Solid Earth", "locations": "Antarctica", "north": -77.0, "nsf_funding_programs": null, "persons": "Ashworth, Allan; Lewis, Adam", "project_titles": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "projects": [{"proj_uid": "p0000188", "repository": "USAP-DC", "title": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "uid": "600081", "west": 160.0}, {"awards": "0817163 Reiners, Peter", "bounds_geometry": ["POLYGON((72 -66,72.3 -66,72.6 -66,72.9 -66,73.2 -66,73.5 -66,73.8 -66,74.1 -66,74.4 -66,74.7 -66,75 -66,75 -66.3,75 -66.6,75 -66.9,75 -67.2,75 -67.5,75 -67.8,75 -68.1,75 -68.4,75 -68.7,75 -69,74.7 -69,74.4 -69,74.1 -69,73.8 -69,73.5 -69,73.2 -69,72.9 -69,72.6 -69,72.3 -69,72 -69,72 -68.7,72 -68.4,72 -68.1,72 -67.8,72 -67.5,72 -67.2,72 -66.9,72 -66.6,72 -66.3,72 -66))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This Small Grant for Exploratory Research investigates the origin and evolution of the Gamburtsev subglacial mountains (GSM). These mountains are considered the nucleation point for Antarctica\u0027s largest ice sheets; however, being of indeterminate age, they may postdate ice sheet formation. As well, their formation could reflect tectonic events during the breakup of Gondwana. The project studies GSM-derived detrital zircon and apatite crystals from Prydz Bay obtained by the Ocean Drilling Program. Analytical work includes triple-dating thermochronometry by U/Pb, fission track, and (U/Th)/He methods. The combined technique offers insight into both high and low temperature processes, and is potentially sensitive to both the orogenic events and the subsequent cooling and exhumation due to erosion. In terms of broader impacts, this project supports research for a postdoctoral fellow.", "east": 75.0, "geometry": ["POINT(73.5 -67.5)"], "keywords": "Antarctica; Gamburtsev Mountains; Geochronology; Marine Sediments; NBP0101; ODP1166; Prydz Bay; Solid Earth; Southern Ocean", "locations": "Antarctica; 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": "0230260 Bender, Michael", "bounds_geometry": ["POINT(106.8 -72.4667)"], "date_created": "Tue, 10 Jul 2007 00:00:00 GMT", "description": "This data set includes a time scale for the Vostok ice core, retrieved from Vostok Station on the East Antarctic Plateau. This chronology is derived by orbitally tuning to molecular oxygen to nitrogen (O\u003csub\u003e2\u003c/sub\u003e/N\u003csub\u003e2\u003c/sub\u003e) ratios in occluded air for depths deeper than 1550 m (greater than 112,000 years old), and by gas correlation to the Greenland Ice Sheet Project 2 (GISP2) chronology for the ice core section that is shallower than 1422 m (less than 102,000 years old). Because of poor gas preservation in air bubbles in shallower depths, investigators could only constrain the Vostok chronology for the section deeper than 1550 m by O\u003csub\u003e2\u003c/sub\u003e/N\u003csub\u003e2\u003c/sub\u003e. Thus for the shallower section of the core, they synchronized the Vostok delta oxygen-18 (\u0026delta;\u003csup\u003e18\u003c/sup\u003eO) and methane (CH\u003csub\u003e4\u003c/sub\u003e) measurements to those of the GISP2 to obtain the chronology (see Bender, et al. 2006). Note, CH\u003csub\u003e4\u003c/sub\u003e data are not included in this data set.\n\nInvestigators analyzed the O\u003csub\u003e2\u003c/sub\u003e/N\u003csub\u003e2\u003c/sub\u003e and the\u003cem\u003e\u003cstrong\u003e \u003c/strong\u003e\u003c/em\u003e\u0026delta;\u003csup\u003e18\u003c/sup\u003eO record ratios for approximately the past 115,000 to 400,000 years in the Vostok ice core. They combined new measurements for O\u003csub\u003e2\u003c/sub\u003e/N\u003csub\u003e2\u003c/sub\u003e and \u0026delta;\u003csup\u003e18\u003c/sup\u003eO with data from Bender (2002) and Petit, et al. (1999), respectively.\n\nData are in Microsoft Excel format and are available via FTP.", "east": 106.8, "geometry": ["POINT(106.8 -72.4667)"], "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Lake Vostok; Paleoclimate; Vostok; Vostok Ice Core", "locations": "Lake Vostok; Antarctica; Vostok", "north": -72.4667, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Bender, Michael; Suwa, Makoto", "project_titles": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core", "projects": [{"proj_uid": "p0000257", "repository": "USAP-DC", "title": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.4667, "title": "Trapped Gas Composition and Chronology of the Vostok Ice Core", "uid": "609311", "west": 106.8}, {"awards": "0126343 Nishiizumi, Kunihiko", "bounds_geometry": ["POINT(-148.812 -81.6588)"], "date_created": "Thu, 31 May 2007 00:00:00 GMT", "description": "This data set includes a record of cosmogenic radionuclide concentrations in the Siple Dome A ice core collected as part of the West Antarctic ice core program. The investigators measured profiles of both \u003csup\u003e10\u003c/sup\u003eBe (half-life = 1.5x10\u003csup\u003e6\u003c/sup\u003e years) and \u003csup\u003e36\u003c/sup\u003eCl (half-life = 3.0x10\u003csup\u003e5\u003c/sup\u003e years) in the entire ice core, which spans the time period from the present to about 100,000 years before present. These data are being used for perfecting the ice core chronology, deducing the history of solar activity, deducing the history of variations in the geomagnetic field, and studying the possible role of solar variations on climate. \n\nData are distributed as a PDF file and are available via FTP.", "east": -148.812, "geometry": ["POINT(-148.812 -81.6588)"], "keywords": "Antarctica; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Siple Dome; Antarctica", "north": -81.6588, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Finkel, R. C.; Nishiizumi, Kunihiko", "project_titles": "Cosmogenic Radionuclides in the Siple Dome Ice Core", "projects": [{"proj_uid": "p0000358", "repository": "USAP-DC", "title": "Cosmogenic Radionuclides in the Siple Dome Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.6588, "title": "Cosmogenic Radionuclides in the Siple Dome A Ice Core", "uid": "609307", "west": -148.812}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
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 |
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 |
Joinville and Livingston Islands - rock and sediment OSL ages
|
1643868 1644197 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
detailed results for rock and sediment OSL ages; De calculation; dose rate calculation, fading, signal measurement | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
OSL data - Joinville and Livingston Islands - Raw data
|
1643868 1644197 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
raw OSL data for rock and sediment samples collected on Joinville and Livingston Islands | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches
|
1644197 1643868 |
2022-03-11 | DeWitt, Regina |
Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches |
sediment and rock samples were collected on Joinville and Livingston Islands for OSL dating; feldspar separates were prepared; data set includes Electron microprobe analysis of selected feldspar extracts; includes bmp and tif with elemental maps plus elemental concentrations and Ca:Na:K ratios for feldspar analysis | ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"] | ["POINT(-60 -63)"] | false | false |
Apatite (U-Th)/He and TREE Data Central Transantarctic Mountains
|
1443556 |
2021-07-13 | Thomson, Stuart; He, John; Reiners, Peter; Hemming, Sidney R.; Licht, Kathy |
Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis |
List of supplementary tables from publication He, J., Thomson, S.N., Reiners, P.W., Hemming, S.R., and Licht, K.J., 2021, Rapid erosion of the central Transantarctic Mountains at the Eocene-Oligocene transition: Evidence from skewed (U-Th)/He date distributions near Beardmore Glacier: Earth and Planetary Science Letters, v. 567, p. 117009, doi:10.1016/j.epsl.2021.117009. Supp. Table 1 U-Th/He data Supp. Table 2 Trace and REE data Supp. Table 3 Compilation with elevation-weighted resampling Supp. Table 4 Summary statistics and sampling distribution of large-n samples and compilations. Supp. Table 5 Perpendicular distance of BAR and CMK sample to Kukri Peneplain Supp. Table 6 Compilation of apatite He data from east Antarctica used in Fig. 1 | ["POLYGON((-180 -83.5,-178 -83.5,-176 -83.5,-174 -83.5,-172 -83.5,-170 -83.5,-168 -83.5,-166 -83.5,-164 -83.5,-162 -83.5,-160 -83.5,-160 -83.75,-160 -84,-160 -84.25,-160 -84.5,-160 -84.75,-160 -85,-160 -85.25,-160 -85.5,-160 -85.75,-160 -86,-162 -86,-164 -86,-166 -86,-168 -86,-170 -86,-172 -86,-174 -86,-176 -86,-178 -86,180 -86,179 -86,178 -86,177 -86,176 -86,175 -86,174 -86,173 -86,172 -86,171 -86,170 -86,170 -85.75,170 -85.5,170 -85.25,170 -85,170 -84.75,170 -84.5,170 -84.25,170 -84,170 -83.75,170 -83.5,171 -83.5,172 -83.5,173 -83.5,174 -83.5,175 -83.5,176 -83.5,177 -83.5,178 -83.5,179 -83.5,-180 -83.5))"] | ["POINT(-175 -84.75)"] | false | false |
Volcanological and Petrological measurements on Mt. Early and Sheridan Bluff volcanoes, upper Scott Glacier, Antarctica
|
1443576 |
2020-06-05 | Panter, Kurt |
Investigating Early Miocene Sub-ice Volcanoes in Antarctica for Improved Modeling and understanding of a Large Magmatic Province |
Mt. Early and Sheridan Bluff (87°S) are the above ice expression of Earth’s southernmost volcanic field that lies approximately 300 km from the South Pole. The dataset supplies the locations and lithological descriptions of the units that the samples were collected from for dating and petrological study. Fundamental compositional information on the mafic volcanic rock samples include whole rock MgO concentrations (wt.%), the forsterite content of olivine and the oxygen isotopic composition of olivine. The dataset also provides a record of what samples have been analyzed for major and trace elements by XRF and ICP-MS, mineral chemistry by EMPA, radiogenic isotopes of Sr, Nd and Pb on whole rock powders by ICP-MS and dating by 40Ar/39Ar method. | ["POLYGON((-154.1 -86.9,-154.03 -86.9,-153.96 -86.9,-153.89 -86.9,-153.82 -86.9,-153.75 -86.9,-153.68 -86.9,-153.61 -86.9,-153.54 -86.9,-153.47 -86.9,-153.4 -86.9,-153.4 -86.92,-153.4 -86.94,-153.4 -86.96,-153.4 -86.98,-153.4 -87,-153.4 -87.02,-153.4 -87.04,-153.4 -87.06,-153.4 -87.08,-153.4 -87.1,-153.47 -87.1,-153.54 -87.1,-153.61 -87.1,-153.68 -87.1,-153.75 -87.1,-153.82 -87.1,-153.89 -87.1,-153.96 -87.1,-154.03 -87.1,-154.1 -87.1,-154.1 -87.08,-154.1 -87.06,-154.1 -87.04,-154.1 -87.02,-154.1 -87,-154.1 -86.98,-154.1 -86.96,-154.1 -86.94,-154.1 -86.92,-154.1 -86.9))"] | ["POINT(-153.75 -87)"] | false | false |
Detrital low-temperature thermochronometry from Bourgeois Fjord, AP
|
1543256 |
2020-02-27 | Clinger, Anna |
Antarctic Peninsula Exhumation and Landscape Development Investigated by Low-Temperature Detrital Thermochronometry |
This dataset contains 80 detrital and 2 bedrock apatite (U-Th)/He thermochronometric ages from Bourgeois Fjord. Data was collected to constrain timing and patterns of topographic change at Bourgeois Fjord on Ma timescales. Analyses were conducted at the Berkeley Geochronology Center and presented in Microsoft Excel formats. | ["POLYGON((-66.80688 -67.420674,-66.732895 -67.420674,-66.65891 -67.420674,-66.584925 -67.420674,-66.51094 -67.420674,-66.436955 -67.420674,-66.36297 -67.420674,-66.288985 -67.420674,-66.215 -67.420674,-66.141015 -67.420674,-66.06703 -67.420674,-66.06703 -67.4542151,-66.06703 -67.4877562,-66.06703 -67.5212973,-66.06703 -67.5548384,-66.06703 -67.5883795,-66.06703 -67.6219206,-66.06703 -67.6554617,-66.06703 -67.6890028,-66.06703 -67.7225439,-66.06703 -67.756085,-66.141015 -67.756085,-66.215 -67.756085,-66.288985 -67.756085,-66.36297 -67.756085,-66.436955 -67.756085,-66.51094 -67.756085,-66.584925 -67.756085,-66.65891 -67.756085,-66.732895 -67.756085,-66.80688 -67.756085,-66.80688 -67.7225439,-66.80688 -67.6890028,-66.80688 -67.6554617,-66.80688 -67.6219206,-66.80688 -67.5883795,-66.80688 -67.5548384,-66.80688 -67.5212973,-66.80688 -67.4877562,-66.80688 -67.4542151,-66.80688 -67.420674))"] | ["POINT(-66.436955 -67.5883795)"] | false | false |
Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula
|
1826712 1443386 1443585 1443424 |
2019-09-24 | Emslie, Steven D. |
Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators |
Radiocarbon dates from pygoscelid penguin tissues from ornithogenic soils and beach deposits at Stranger Point, King George (25 de Mayo) Island, Antarctic Peninsula. Uncorrected dates are in radiocarbon years before present (BP); calibrated dates were corrected for the marine carbon reservoir effect (delta R = 700 +/- 50 years) and calibrated with Calib 7.0.4 to provide 2σ ranges in calendar years BP. All dates except were completed at the Woods Hole National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility and are designated with OS numbers. Localities include ancient penguin breedings sites (mounds, M), active colonies (I9, B3), and a mid-Holocene marine beach deposit (Pingfo 1). | ["POLYGON((-59 -62,-58.9 -62,-58.8 -62,-58.7 -62,-58.6 -62,-58.5 -62,-58.4 -62,-58.3 -62,-58.2 -62,-58.1 -62,-58 -62,-58 -62.1,-58 -62.2,-58 -62.3,-58 -62.4,-58 -62.5,-58 -62.6,-58 -62.7,-58 -62.8,-58 -62.9,-58 -63,-58.1 -63,-58.2 -63,-58.3 -63,-58.4 -63,-58.5 -63,-58.6 -63,-58.7 -63,-58.8 -63,-58.9 -63,-59 -63,-59 -62.9,-59 -62.8,-59 -62.7,-59 -62.6,-59 -62.5,-59 -62.4,-59 -62.3,-59 -62.2,-59 -62.1,-59 -62))"] | ["POINT(-58.5 -62.5)"] | false | false |
Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)
|
1443680 |
2019-07-16 | Eidam, Emily; Nittrouer, Charles; Homolka, Khadijah; Smith, Craig |
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco) |
This dataset includes Pb-210 activities, grain-size distributions, and x-radiograph negatives for cores collected primarily during NBP1603 (and also LMG1510) as part of the FjordEco project in Andvord Bay and surrounding areas (Gerlache Strait, and Station B on the shelf). Data are from subsampled intervals of kasten cores and box cores, as well as one megacore. Samples were x-rayed, sliced, and bagged onboard the vessel. Grain-size and Pb-210 analyses were completed in the Sediment Dynamics Lab within the University of Washington School of Oceanography (PI C. Nittrouer). | ["POLYGON((-65.561 -64.6538,-65.2471 -64.6538,-64.9332 -64.6538,-64.6193 -64.6538,-64.3054 -64.6538,-63.9915 -64.6538,-63.6776 -64.6538,-63.3637 -64.6538,-63.0498 -64.6538,-62.7359 -64.6538,-62.422 -64.6538,-62.422 -64.67842,-62.422 -64.70304,-62.422 -64.72766,-62.422 -64.75228,-62.422 -64.7769,-62.422 -64.80152,-62.422 -64.82614,-62.422 -64.85076,-62.422 -64.87538,-62.422 -64.9,-62.7359 -64.9,-63.0498 -64.9,-63.3637 -64.9,-63.6776 -64.9,-63.9915 -64.9,-64.3054 -64.9,-64.6193 -64.9,-64.9332 -64.9,-65.2471 -64.9,-65.561 -64.9,-65.561 -64.87538,-65.561 -64.85076,-65.561 -64.82614,-65.561 -64.80152,-65.561 -64.7769,-65.561 -64.75228,-65.561 -64.72766,-65.561 -64.70304,-65.561 -64.67842,-65.561 -64.6538))"] | ["POINT(-63.9915 -64.7769)"] | false | false |
Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour Island, Antarctica
|
1543031 |
2019-04-22 | Judd, Emily |
Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica |
Serially-sampled high-resolution organic carbon isotope data from middle Eocene (~42 Ma) driftwood preserved within the La Meseta Formation, Seymour Island, Antarctica. | ["POLYGON((-57 -64,-56.9 -64,-56.8 -64,-56.7 -64,-56.6 -64,-56.5 -64,-56.4 -64,-56.3 -64,-56.2 -64,-56.1 -64,-56 -64,-56 -64.05,-56 -64.1,-56 -64.15,-56 -64.2,-56 -64.25,-56 -64.3,-56 -64.35,-56 -64.4,-56 -64.45,-56 -64.5,-56.1 -64.5,-56.2 -64.5,-56.3 -64.5,-56.4 -64.5,-56.5 -64.5,-56.6 -64.5,-56.7 -64.5,-56.8 -64.5,-56.9 -64.5,-57 -64.5,-57 -64.45,-57 -64.4,-57 -64.35,-57 -64.3,-57 -64.25,-57 -64.2,-57 -64.15,-57 -64.1,-57 -64.05,-57 -64))"] | ["POINT(-56.5 -64.25)"] | false | false |
2016 Paleomagnetic samples from the James Ross Basin, Antarctica
|
1341729 |
2018-04-27 | Skinner, Steven; Kirschvink, Joseph |
Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica |
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NBP1502A Cruise Core Data
|
1246353 |
2018-02-05 | Simkins, Lauren; Anderson, John; Prothro, Lindsay |
Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. |
Dataset includes details of cores collected as part of cruise NBP1502A, a list of radiocarbon-dated samples and samples to be radiocarbon-dated, and grain-size data from select NBP1502A cores. | ["POLYGON((-180 -74.37,-178.85 -74.37,-177.7 -74.37,-176.55 -74.37,-175.4 -74.37,-174.25 -74.37,-173.1 -74.37,-171.95 -74.37,-170.8 -74.37,-169.65 -74.37,-168.5 -74.37,-168.5 -74.747,-168.5 -75.124,-168.5 -75.501,-168.5 -75.878,-168.5 -76.255,-168.5 -76.632,-168.5 -77.009,-168.5 -77.386,-168.5 -77.763,-168.5 -78.14,-169.65 -78.14,-170.8 -78.14,-171.95 -78.14,-173.1 -78.14,-174.25 -78.14,-175.4 -78.14,-176.55 -78.14,-177.7 -78.14,-178.85 -78.14,180 -78.14,178.48 -78.14,176.96 -78.14,175.44 -78.14,173.92 -78.14,172.4 -78.14,170.88 -78.14,169.36 -78.14,167.84 -78.14,166.32 -78.14,164.8 -78.14,164.8 -77.763,164.8 -77.386,164.8 -77.009,164.8 -76.632,164.8 -76.255,164.8 -75.878,164.8 -75.501,164.8 -75.124,164.8 -74.747,164.8 -74.37,166.32 -74.37,167.84 -74.37,169.36 -74.37,170.88 -74.37,172.4 -74.37,173.92 -74.37,175.44 -74.37,176.96 -74.37,178.48 -74.37,-180 -74.37))"] | ["POINT(178.15 -76.255)"] | false | false |
Hatherton Glacier Radiocarbon Data
|
1246170 |
2017-10-23 | Hall, Brenda |
Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier |
Hatherton Glacier Radiocarbon Data | ["POLYGON((155.4 -79.8,155.54 -79.8,155.68 -79.8,155.82 -79.8,155.96 -79.8,156.1 -79.8,156.24 -79.8,156.38 -79.8,156.52 -79.8,156.66 -79.8,156.8 -79.8,156.8 -79.82,156.8 -79.84,156.8 -79.86,156.8 -79.88,156.8 -79.9,156.8 -79.92,156.8 -79.94,156.8 -79.96,156.8 -79.98,156.8 -80,156.66 -80,156.52 -80,156.38 -80,156.24 -80,156.1 -80,155.96 -80,155.82 -80,155.68 -80,155.54 -80,155.4 -80,155.4 -79.98,155.4 -79.96,155.4 -79.94,155.4 -79.92,155.4 -79.9,155.4 -79.88,155.4 -79.86,155.4 -79.84,155.4 -79.82,155.4 -79.8))"] | ["POINT(156.1 -79.9)"] | false | false |
Antarctic Tephra Data Base AntT static web site
|
1142007 1142069 |
2017-09-13 | Kurbatov, Andrei V.; Dunbar, Nelia |
Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT) |
This collaborative interdisciplinary research project aims to consolidate, into a single user-friendly database, information about volcanic products detected in Antarctica. By consolidating information about volcanic sources, and physical and geochemical characteristics of volcanic products, this systematic data collection approach will improve the ability of researchers to identify volcanic ash, or tephra, from specific volcanic eruptions that may be spread over large areas in a geologically instantaneous amount of time. AntT database is designed to assist in the identification and cross-correlation of time intervals in various paleoclimate archives that contain volcanic layers from often unknown sources. | ["POLYGON((0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,216 -60,252 -60,288 -60,324 -60,360 -60,360 -63,360 -66,360 -69,360 -72,360 -75,360 -78,360 -81,360 -84,360 -87,360 -90,324 -90,288 -90,252 -90,216 -90,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,0 -87,0 -84,0 -81,0 -78,0 -75,0 -72,0 -69,0 -66,0 -63,0 -60))"] | ["POINT(180 -75)"] | false | false |
Antarctic Ice Core Tephra Analysis
|
1142007 |
2017-08-03 | Kurbatov, Andrei V. |
Collaborative Research: Developing an Antarctic Tephra Database for Interdisciplinary Paleoclimate Research (AntT) |
This dataset contains ice core tephra geochemical data from 5 temporal intervals in the RICE, WDC-06A, SPRESSO, and SPICE ice cores. The temporal intervals included are 1991 C.E., 1963 C.E., 1815 C.E., 1809 C.E., and 1257 C.E. These intervals are often analyzed for volcanic sulfate by ice core scientists. The volcanic events associated with these intervals caused global weather and climate phenomena and are often used by climate modelers as well to understand volcanic sulfate loading on the climate. | ["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 |
Snowpit evidence of the 2011 Puyehue-Cordon Caulle (Chile) eruption in West Antarctica
|
0636740 |
2017-07-11 | Koffman, Bess; Kreutz, Karl |
Collaborative Research: Microparticle/tephra analysis of the WAIS Divide ice core |
We present several related datasets from a 2012 snow pit and a 2013 firn core collected near the WAIS Divide field camp in West Antarctica. The data include soluble ions (sodium and non-sea-salt sulfate) and dust particle concentrations, as well as major oxide geochemistry of tephra grains isolated from snow samples. Based on these data, we found evidence of deposition from the 2011 Puyehue Cordon-Caulle (Chile) volcanic eruption at WAIS Divide. | ["POINT(-112.086 -79.468)"] | ["POINT(-112.086 -79.468)"] | false | false |
WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)
|
0944197 |
2017-03-28 | Fudge, T. J. |
Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core |
The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ~68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8-31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age-ice age difference (Delta age) using a combination of firn densification modeling, ice-flow modeling, and a data set of d15N-N2, a proxy for past firn column thickness. The largest Delta age at WD occurs during the Last Glacial Maximum, and is 525 +/- 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard-Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Delta age at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the \"bipolar seesaw\". We present the WD2014 chronology for the upper part (0-2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of 10Be from WAIS Divide and 14C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5% of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1% of the age at three abrupt climate change events between 27 and 31ka. WD2014 has consistently younger ages than Greenland ice core chronologies during most of the Holocene. For the Younger Dryas-Preboreal transition (11.595 ka; 24 years younger) and the Bolling-Allerod Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity, atmospheric mineral dust, and atmospheric methane concentrations. | ["POINT(-112.1115 -79.481)"] | ["POINT(-112.1115 -79.481)"] | false | false |
WAIS Divide Ice-Core Chronology from Intermediate Core WDC05Q
|
0538427 |
2017-03-28 | McConnell, Joseph |
Trace and Ultra-Trace Chemistry Measurements of the WAIS Divide Ice Core |
A state-of-the-art continuous ice core analytical system was used to analyze samples from 0 to ~130 m depth of the recently collected intermediate core WDC05Q from West Antarctica. Interpretation of these records and publication of findings is ongoing. | ["POINT(-112.1115 -79.481)"] | ["POINT(-112.1115 -79.481)"] | false | false |
Cosmogenic Radionuclides in the WAIS Divide Ice Core
|
0636964 |
2016-12-14 | Welten, Kees |
Collaborative Research: Cosmogenic Radionuclides in the Deep WAIS Divide Core |
None | ["POINT(-112.1115 -79.481)"] | ["POINT(-112.1115 -79.481)"] | false | false |
Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins
|
1043554 |
2016-11-09 | Willenbring, Jane |
Collaborative Research: Activation of high-elevation alluvial fans in the Transantarctic Mountains - a proxy for Plio-Pleistocene warmth along East Antarctic ice margins |
The PIs propose to address the question of whether ice surface melting zones developed at high elevations during warm climatic phases in the Transantarctic Mountains. Evidence from sediment cores drilled by the ANDRILL program indicates that open water in the Ross Sea could have been a source of warmth during Pliocene and Pleistocene. The question is whether marine warmth penetrated inland to the ice sheet margins. The glacial record may be ill suited to answer this question, as cold-based glaciers may respond too slowly to register brief warmth. Questions also surround possible orbital controls on regional climate and ice sheet margins. Northern Hemisphere insolation at obliquity and precession timescales is thought to control Antarctic climate through oceanic or atmospheric connections, but new thinking suggests that the duration of Southern Hemisphere summer may be more important. The PIs propose to use high elevation alluvial deposits in the Transantarctic Mountains as a proxy for inland warmth. These relatively young fans, channels, and debris flow levees stand out as visible evidence for the presence of melt water in an otherwise ancient, frozen landscape. Based on initial analyses of an alluvial fan in the Olympus Range, these deposits are sensitive recorders of rare melt events that occur at orbital timescales. For their study they will 1) map alluvial deposits using aerial photography, satellite imagery and GPS assisted field surveys to establish water sources and to quantify parameters effecting melt water production, 2) date stratigraphic sequences within these deposits using OSL, cosmogenic nuclide, and interbedded volcanic ash chronologies, 3) use paired nuclide analyses to estimate exposure and burial times, and rates of deposition and erosion, and 4) use micro and regional scale climate modeling to estimate paleoenvironmental conditions associated with melt events. This study will produce a record of inland melting from sites adjacent to ice sheet margins to help determine controls on regional climate along margins of the East Antarctic Ice Sheet to aid ice sheet and sea level modeling studies. The proposal will support several graduate and undergraduates. A PhD student will be supported on existing funding. The PIs will work with multiple K-12 schools to conduct interviews and webcasts from Antarctica and they will make follow up visits to classrooms after the field season is complete. | ["POINT(161.5 -77.5)"] | ["POINT(161.5 -77.5)"] | false | false |
Reedy Glacier Exposure Ages, Antarctica
|
0229314 |
2015-03-30 | Stone, John |
Collaborative Research: Late Quaternary History of Reedy Glacier |
This data set contains site, sample, and analytical data from which to calculate cosmogenic nuclide-based exposure ages for glacial deposits adjacent to Reedy Glacier, Antarctica. The data are formatted as input for the CRONUS online exposure-age calculator (http://www.hess.ess.edu/), which determines the exposure age from the cosmogenic Beryllium-10 and Aluminum-26 production rates. | ["POLYGON((-136.32 -85.38,-135.136 -85.38,-133.952 -85.38,-132.768 -85.38,-131.584 -85.38,-130.4 -85.38,-129.216 -85.38,-128.032 -85.38,-126.848 -85.38,-125.664 -85.38,-124.48 -85.38,-124.48 -85.493,-124.48 -85.606,-124.48 -85.719,-124.48 -85.832,-124.48 -85.945,-124.48 -86.058,-124.48 -86.171,-124.48 -86.284,-124.48 -86.397,-124.48 -86.51,-125.664 -86.51,-126.848 -86.51,-128.032 -86.51,-129.216 -86.51,-130.4 -86.51,-131.584 -86.51,-132.768 -86.51,-133.952 -86.51,-135.136 -86.51,-136.32 -86.51,-136.32 -86.397,-136.32 -86.284,-136.32 -86.171,-136.32 -86.058,-136.32 -85.945,-136.32 -85.832,-136.32 -85.719,-136.32 -85.606,-136.32 -85.493,-136.32 -85.38))"] | ["POINT(-130.4 -85.945)"] | false | false |
Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica
|
0739575 |
2015-01-01 | Patterson, William; Polito, Michael; Emslie, Steven D. |
Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica |
The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor's theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information. | ["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 |
Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica
|
1142156 |
2015-01-01 | Marschall, Horst |
Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica |
Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth's crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica. Dronning Maud Land (DML) occupied a central location during the formation of supercontinents - large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth's history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007-2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML. | ["POLYGON((-6.44 -71.93,-5.378 -71.93,-4.316 -71.93,-3.254 -71.93,-2.192 -71.93,-1.13 -71.93,-0.068 -71.93,0.994 -71.93,2.056 -71.93,3.118 -71.93,4.18 -71.93,4.18 -71.998,4.18 -72.066,4.18 -72.134,4.18 -72.202,4.18 -72.27,4.18 -72.338,4.18 -72.406,4.18 -72.474,4.18 -72.542,4.18 -72.61,3.118 -72.61,2.056 -72.61,0.994 -72.61,-0.068 -72.61,-1.13 -72.61,-2.192 -72.61,-3.254 -72.61,-4.316 -72.61,-5.378 -72.61,-6.44 -72.61,-6.44 -72.542,-6.44 -72.474,-6.44 -72.406,-6.44 -72.338,-6.44 -72.27,-6.44 -72.202,-6.44 -72.134,-6.44 -72.066,-6.44 -71.998,-6.44 -71.93))"] | ["POINT(-1.13 -72.27)"] | false | false |
High-resolution Atmospheric CO2 during 7.4-9.0 ka
|
0944764 |
2014-06-25 | Brook, Edward J.; Ahn, Jinho |
Atmospheric CO2 and Abrupt Climate Change |
This data set provides a new CO2 record from the Siple Dome ice core, Antarctica, that covers 7.4-9.0 ka (thousand years) with 8- to 16-year resolution. A small, about 1-2 ppm, increase of atmospheric CO2 during the 8.2 ka event was observed. The increase is not significant when compared to other centennial variations in the Holocene that are not linked to large temperature changes. The results do not agree with leaf stomata records that suggest a CO2 decrease of up to ~25 ppm and imply that the sensitivity of atmospheric CO2 to the primarily northern hemisphere cooling of the 8.2 ka event was limited. | ["POINT(-148.82 -81.66)"] | ["POINT(-148.82 -81.66)"] | 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 |
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 |
Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology
|
0838729 |
2011-01-01 | Hemming, Sidney R. |
Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology |
Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion. | ["POLYGON((-67.2 -58,-43.98 -58,-20.76 -58,2.46 -58,25.68 -58,48.9 -58,72.12 -58,95.34 -58,118.56 -58,141.78 -58,165 -58,165 -59.2,165 -60.4,165 -61.6,165 -62.8,165 -64,165 -65.2,165 -66.4,165 -67.6,165 -68.8,165 -70,141.78 -70,118.56 -70,95.34 -70,72.12 -70,48.9 -70,25.68 -70,2.46 -70,-20.76 -70,-43.98 -70,-67.2 -70,-67.2 -68.8,-67.2 -67.6,-67.2 -66.4,-67.2 -65.2,-67.2 -64,-67.2 -62.8,-67.2 -61.6,-67.2 -60.4,-67.2 -59.2,-67.2 -58))"] | ["POINT(48.9 -64)"] | false | false |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals
|
0902957 |
2011-01-01 | Robinson, Laura |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals |
The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column. | ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"] | ["POINT(-52.75 -58)"] | false | false |
Continued Research on the Jurassic Vertebrate Fauna from the Beardmore Glacier Region of Antarctica
|
0634619 |
2010-01-01 | Hammer, William R. |
Continued Research on the Jurassic Vertebrate Fauna from the Beardmore Glacier Region of Antarctica |
This award supports preparation and study of fossil dinosaurs discovered on Mt. Kirkpatrick, Antarctica, during the 2003-04 field season. The 4,000 pounds of bone bearing matrix to be processed includes new pieces of Cryolophosaurus, a 22 foot long meat eating theropod, as well as a new unnamed sauropod dinosaur and other yet to be identified taxa. This project advances our understanding of dinosaur evolution and adaptation at the beginning of the reign of the dinosaurs, the Late Triassic and Early Jurassic. This period is poorly understood due to lack of fossils, which makes these fossils from Antarctica particularly unique. Also, since these fossils are from high paleolatitudes they will contribute to our understanding of past climates and the physiologic adaptations of dinosaurs to lengthy periods of darkness. The broader impacts include outreach to the general public through museum exhibits and presentations. | ["POINT(166 -84)"] | ["POINT(166 -84)"] | false | false |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes
|
0538580 |
2010-01-01 | van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R. |
Antarctica's Geological History Reflected in Sedimentary Radiogenic Isotopes |
This project studies sediment from the ocean floor to understand Antarctica's geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work's central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry. | ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"] | ["POINT(120 -65)"] | false | false |
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 |
Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?
|
0228842 |
2009-01-01 | Grew, Edward |
Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust? |
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts per million in rocks subjected to conditions of the middle and lower crust, that is, temperatures of 700 degrees C or more in the granulite-facies, which is characterized by very low water activities at pressures of 5 to 10 kbar (18-35 km burial). Devolatization reactions with loss of aqueous fluid and partial melting with removal of melt have been cited as primary causes for boron depletion under granulite-facies conditions. Despite the pervasiveness of both these processes, rocks rich in boron are locally found in the granulite-facies, that is, there are mechanisms for retaining boron during the metamorphic process. The Larsemann Hills, Prydz Bay, Antarctica, are a prime example. More than 20 lenses and layered bodies containing four borosilicate mineral species crop out over a 50 square kilometer area, which thus would be well suited for research on boron-rich granulite-facies metamorphic rocks. While most investigators have focused on the causes for loss of boron, this work will investigate how boron is retained during high-grade metamorphism. Field observations and mapping in the Larsemann Hills, chemical analyses of minerals and their host rocks, and microprobe age dating will be used to identify possible precursors and deduce how the precursor materials recrystallized into borosilicate rocks under granulite-facies conditions. The working hypothesis is that high initial boron content facilitates retention of boron during metamorphism because above a certain threshold boron content, a mechanism 'kicks in' that facilitates retention of boron in metamorphosed rocks. For example, in a rock with large amounts of the borosilicate tourmaline, such as stratabound tourmalinite, the breakdown of tourmaline to melt could result in the formation of prismatine and grandidierite, two borosilicates found in the Larsemann Hills. This situation is rarely observed in rocks with modest boron content, in which breakdown of tourmaline releases boron into partial melts, which in turn remove boron when they leave the system. Stratabound tourmalinite is associated with manganese-rich quartzite, phosphorus-rich rocks and sulfide concentrations that could be diagnostic for recognizing a tourmalinite protolith in a highly metamorphosed complex where sedimentary features have been destroyed by deformation. Because partial melting plays an important role in the fate of boron during metamorphism, our field and laboratory research will focus on the relationship between the borosilicate units, granite pegmatites and other granitic intrusives. The results of our study will provide information on cycling of boron at deeper levels in the Earth's crust and on possible sources of boron for granites originating from deep-seated rocks. An undergraduate student will participate in the electron microprobe age-dating of monazite and xenotime as part of a senior project, thereby integrating the proposed research into the educational mission of the University of Maine. In response to a proposal for fieldwork, the Australian Antarctic Division, which maintains Davis station near the Larsemann Hills, has indicated that they will support the Antarctic fieldwork. | ["POLYGON((76 -69.3,76.05 -69.3,76.1 -69.3,76.15 -69.3,76.2 -69.3,76.25 -69.3,76.3 -69.3,76.35 -69.3,76.4 -69.3,76.45 -69.3,76.5 -69.3,76.5 -69.32,76.5 -69.34,76.5 -69.36,76.5 -69.38,76.5 -69.4,76.5 -69.42,76.5 -69.44,76.5 -69.46,76.5 -69.48,76.5 -69.5,76.45 -69.5,76.4 -69.5,76.35 -69.5,76.3 -69.5,76.25 -69.5,76.2 -69.5,76.15 -69.5,76.1 -69.5,76.05 -69.5,76 -69.5,76 -69.48,76 -69.46,76 -69.44,76 -69.42,76 -69.4,76 -69.38,76 -69.36,76 -69.34,76 -69.32,76 -69.3))"] | ["POINT(76.25 -69.4)"] | false | false |
Occupation History and Diet of Adelie Penguins in the Ross Sea Region
|
0125098 |
2009-01-01 | Emslie, Steven D. |
Occupation History and Diet of Adelie Penguins in the Ross Sea Region |
This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. Other data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC. | ["POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))"] | ["POINT(55 -75)"] | false | false |
Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores
|
0739496 |
2009-01-01 | Furbish, David; Miller, Molly |
Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores |
This project answers a simple question: why are there so few fossils in sediment cores from Antarctica's continental shelf? Antarctica's benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change. | ["POLYGON((163.41667 -77.33333,163.46667 -77.33333,163.51667 -77.33333,163.56667 -77.33333,163.61667 -77.33333,163.66667 -77.33333,163.71667 -77.33333,163.76667 -77.33333,163.81667 -77.33333,163.86667 -77.33333,163.91667 -77.33333,163.91667 -77.369997,163.91667 -77.406664,163.91667 -77.443331,163.91667 -77.479998,163.91667 -77.516665,163.91667 -77.553332,163.91667 -77.589999,163.91667 -77.626666,163.91667 -77.663333,163.91667 -77.7,163.86667 -77.7,163.81667 -77.7,163.76667 -77.7,163.71667 -77.7,163.66667 -77.7,163.61667 -77.7,163.56667 -77.7,163.51667 -77.7,163.46667 -77.7,163.41667 -77.7,163.41667 -77.663333,163.41667 -77.626666,163.41667 -77.589999,163.41667 -77.553332,163.41667 -77.516665,163.41667 -77.479998,163.41667 -77.443331,163.41667 -77.406664,163.41667 -77.369997,163.41667 -77.33333))"] | ["POINT(163.66667 -77.516665)"] | false | false |
Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains
|
0739693 |
2009-01-01 | Ashworth, Allan; Lewis, Adam |
Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains |
This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia. In terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica's ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise. | ["POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))"] | ["POINT(161 -77.5)"] | false | false |
Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains
|
0817163 |
2009-01-01 | Gehrels, George; Reiners, Peter |
Collaborative Research: SGER: Triple-dating (Pb-FT-He) of Antarctic Detritus and the Origin of the Gamburtsev Mountains |
This Small Grant for Exploratory Research investigates the origin and evolution of the Gamburtsev subglacial mountains (GSM). These mountains are considered the nucleation point for Antarctica's largest ice sheets; however, being of indeterminate age, they may postdate ice sheet formation. As well, their formation could reflect tectonic events during the breakup of Gondwana. The project studies GSM-derived detrital zircon and apatite crystals from Prydz Bay obtained by the Ocean Drilling Program. Analytical work includes triple-dating thermochronometry by U/Pb, fission track, and (U/Th)/He methods. The combined technique offers insight into both high and low temperature processes, and is potentially sensitive to both the orogenic events and the subsequent cooling and exhumation due to erosion. In terms of broader impacts, this project supports research for a postdoctoral fellow. | ["POLYGON((72 -66,72.3 -66,72.6 -66,72.9 -66,73.2 -66,73.5 -66,73.8 -66,74.1 -66,74.4 -66,74.7 -66,75 -66,75 -66.3,75 -66.6,75 -66.9,75 -67.2,75 -67.5,75 -67.8,75 -68.1,75 -68.4,75 -68.7,75 -69,74.7 -69,74.4 -69,74.1 -69,73.8 -69,73.5 -69,73.2 -69,72.9 -69,72.6 -69,72.3 -69,72 -69,72 -68.7,72 -68.4,72 -68.1,72 -67.8,72 -67.5,72 -67.2,72 -66.9,72 -66.6,72 -66.3,72 -66))"] | ["POINT(73.5 -67.5)"] | false | false |
Trapped Gas Composition and Chronology of the Vostok Ice Core
|
0230260 |
2007-07-10 | Bender, Michael; Suwa, Makoto |
Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core |
This data set includes a time scale for the Vostok ice core, retrieved from Vostok Station on the East Antarctic Plateau. This chronology is derived by orbitally tuning to molecular oxygen to nitrogen (O<sub>2</sub>/N<sub>2</sub>) ratios in occluded air for depths deeper than 1550 m (greater than 112,000 years old), and by gas correlation to the Greenland Ice Sheet Project 2 (GISP2) chronology for the ice core section that is shallower than 1422 m (less than 102,000 years old). Because of poor gas preservation in air bubbles in shallower depths, investigators could only constrain the Vostok chronology for the section deeper than 1550 m by O<sub>2</sub>/N<sub>2</sub>. Thus for the shallower section of the core, they synchronized the Vostok delta oxygen-18 (δ<sup>18</sup>O) and methane (CH<sub>4</sub>) measurements to those of the GISP2 to obtain the chronology (see Bender, et al. 2006). Note, CH<sub>4</sub> data are not included in this data set. Investigators analyzed the O<sub>2</sub>/N<sub>2</sub> and the<em><strong> </strong></em>δ<sup>18</sup>O record ratios for approximately the past 115,000 to 400,000 years in the Vostok ice core. They combined new measurements for O<sub>2</sub>/N<sub>2</sub> and δ<sup>18</sup>O with data from Bender (2002) and Petit, et al. (1999), respectively. Data are in Microsoft Excel format and are available via FTP. | ["POINT(106.8 -72.4667)"] | ["POINT(106.8 -72.4667)"] | false | false |
Cosmogenic Radionuclides in the Siple Dome A Ice Core
|
0126343 |
2007-05-31 | Finkel, R. C.; Nishiizumi, Kunihiko |
Cosmogenic Radionuclides in the Siple Dome Ice Core |
This data set includes a record of cosmogenic radionuclide concentrations in the Siple Dome A ice core collected as part of the West Antarctic ice core program. The investigators measured profiles of both <sup>10</sup>Be (half-life = 1.5x10<sup>6</sup> years) and <sup>36</sup>Cl (half-life = 3.0x10<sup>5</sup> years) in the entire ice core, which spans the time period from the present to about 100,000 years before present. These data are being used for perfecting the ice core chronology, deducing the history of solar activity, deducing the history of variations in the geomagnetic field, and studying the possible role of solar variations on climate. Data are distributed as a PDF file and are available via FTP. | ["POINT(-148.812 -81.6588)"] | ["POINT(-148.812 -81.6588)"] | false | false |