USAP-DC

{"dp_type": "Project", "free_text": "Nunataks"}

[{"awards": "1542930 Harbor, Jonathan", "bounds_geometry": "POLYGON((-14.5 -71.5,-13.09 -71.5,-11.68 -71.5,-10.27 -71.5,-8.86 -71.5,-7.45 -71.5,-6.040000000000001 -71.5,-4.630000000000001 -71.5,-3.220000000000001 -71.5,-1.81 -71.5,-0.4 -71.5,-0.4 -71.86,-0.4 -72.22,-0.4 -72.58,-0.4 -72.94,-0.4 -73.3,-0.4 -73.66,-0.4 -74.02,-0.4 -74.38,-0.4 -74.74,-0.4 -75.1,-1.81 -75.1,-3.22 -75.1,-4.63 -75.1,-6.04 -75.1,-7.45 -75.1,-8.86 -75.1,-10.27 -75.1,-11.68 -75.1,-13.09 -75.1,-14.5 -75.1,-14.5 -74.74,-14.5 -74.38,-14.5 -74.02,-14.5 -73.66,-14.5 -73.3,-14.5 -72.94,-14.5 -72.58,-14.5 -72.22,-14.5 -71.86,-14.5 -71.5))", "dataset_titles": "Andersen, Jane L and Newall, Jennifer C and Fredin, Ola and Glasser, Neil F and Lifton, Nathaniel A and Stuart, Finlay M and Fabel, Derek and Caffee, Marc and Pedersen, Vivi K and Koester, Alexandria J and others\r\nA topographic hinge-zone divides coastal and inland ice dynamic regimes in East Antarctica\r\nCommunications Earth \\\u0026 Environment, 2023; Andersen, JL and Newall, JC and Blomdin, R and Sams, SE and Fabel, D and Koester, AJ and Lifton, NA and Fredin, O and Caffee, MW and Glasser, Neil F and others\r\nIce surface changes during recent glacial cycles along the Jutulstraumen and Penck Trough ice streams in western Dronning Maud Land, East Antarctica\r\nQuaternary Science Reviews, 2020; APPLICATIONS OF IN SITU 14C TO GLACIAL LANDSCAPES IN SWEDEN AND ANTARCTICA; Cosmogenic nuclide data from Field Season 3 of Mapping, Measuring, and Modeling Geomorphology and Ice Change in Dronning Maud Land, Antarctica; Suganuma, Yusuke and Kaneda, Heitaro and Mas e Braga, Martim and Ishiwa, Takeshige and Koyama, Takushi and Newall, Jennifer C and Okuno, Jun\u2019ichi and Obase, Takashi and Saito, Fuyuki and Rogozhina, Irina and others\r\nRegional sea-level highstand triggered Holocene ice sheet thinning across coastal Dronning Maud Land, East Antarctica\r\nCommunications Earth \\\u0026 Environment, 2022", "datasets": [{"dataset_uid": "200566", "doi": "10.1038/s43247-022-00673-6", "keywords": null, "people": null, "repository": "ICE-D: Antarctica", "science_program": null, "title": "Andersen, Jane L and Newall, Jennifer C and Fredin, Ola and Glasser, Neil F and Lifton, Nathaniel A and Stuart, Finlay M and Fabel, Derek and Caffee, Marc and Pedersen, Vivi K and Koester, Alexandria J and others\r\nA topographic hinge-zone divides coastal and inland ice dynamic regimes in East Antarctica\r\nCommunications Earth \\\u0026 Environment, 2023", "url": "https://version2.ice-d.org/antarctica/publication/960/"}, {"dataset_uid": "200567", "doi": "10.1016/j.quascirev.2020.106636", "keywords": null, "people": null, "repository": "ICE-D: Antarctica", "science_program": null, "title": "Andersen, JL and Newall, JC and Blomdin, R and Sams, SE and Fabel, D and Koester, AJ and Lifton, NA and Fredin, O and Caffee, MW and Glasser, Neil F and others\r\nIce surface changes during recent glacial cycles along the Jutulstraumen and Penck Trough ice streams in western Dronning Maud Land, East Antarctica\r\nQuaternary Science Reviews, 2020", "url": "https://version2.ice-d.org/antarctica/publication/137/"}, {"dataset_uid": "200568", "doi": "10.1038/s43247-022-00599-z", "keywords": null, "people": null, "repository": "ICE-D: Antarctica", "science_program": null, "title": "Suganuma, Yusuke and Kaneda, Heitaro and Mas e Braga, Martim and Ishiwa, Takeshige and Koyama, Takushi and Newall, Jennifer C and Okuno, Jun\u2019ichi and Obase, Takashi and Saito, Fuyuki and Rogozhina, Irina and others\r\nRegional sea-level highstand triggered Holocene ice sheet thinning across coastal Dronning Maud Land, East Antarctica\r\nCommunications Earth \\\u0026 Environment, 2022", "url": "https://version2.ice-d.org/antarctica/publication/954/"}, {"dataset_uid": "200569", "doi": "10.4231/MVZ8-6F71", "keywords": null, "people": null, "repository": "Purdue University Research Repository", "science_program": null, "title": "Cosmogenic nuclide data from Field Season 3 of Mapping, Measuring, and Modeling Geomorphology and Ice Change in Dronning Maud Land, Antarctica", "url": "https://purr.purdue.edu/publications/5088/1"}, {"dataset_uid": "200565", "doi": "10.25394/PGS.22696426", "keywords": null, "people": null, "repository": "Hammer Research Repository", "science_program": null, "title": "APPLICATIONS OF IN SITU 14C TO GLACIAL LANDSCAPES IN SWEDEN AND ANTARCTICA", "url": "https://hammer.purdue.edu/articles/thesis/APPLICATIONS_OF_IN_SITU_14C_TO_GLACIAL_LANDSCAPES_IN_SWEDEN_AND_ANTARCTICA/22696426?file=40356385"}], "date_created": "Wed, 29 Apr 2026 00:00:00 GMT", "description": "Reconstructing and predicting the response of the Antarctic Ice Sheet to climate change is a major challenge facing the Earth Science community. Computer models of ice sheet behavior are central to addressing this challenge. In this project we tested and improved ice-sheet models by comparing model predictions of past ice extent to the geologic record in Dronning Maud Land, Antarctica. This innovative project collected key geologic data from mountains called nunataks that extend above current and former ice levels that can be used as \"dipsticks\" to reconstruct changes in ice elevation that will be used to improve the models. The end result is both much better knowledge of past three-dimensional changes of the Antarctic Ice Sheet, and improved models that allow for more accurate simulations of potential future changes in the ice sheet. This research fills critical gaps in the geologic record of the pattern and timing of vertical changes in the East Antarctic Ice Sheet in western Dronning Maud Land, by focusing on areas that are critical for differentiating between possible models of past ice sheet configuration. \r\nReconstruction of ice-sheet surface changes involved mapping and cosmogenic nuclide dating of glacially sculpted bedrock, ice-marginal moraines, and erratic boulders at different elevations on nunataks. Patterns of in situ 10Be, 26Al, 14C, and 21Ne concentrations and ratios enabled inferences about the timing and magnitude of changes in maximum ice-surface elevations and periods of burial by non-erosive (cold-based) ice. Results are being integrated with data from other areas to provide insight into changes across the entire Antarctic Ice Sheet, and into the role of large ice sheets in climate evolution and global sea level changes. The field-based results provide constraints against which predictive ice sheet models are being tested and improved, contributing to glaciology, climate and Quaternary science. Broader impacts of this study also advanced the development of the next generation of STEM students and polar scientists. While gaining experience in international collaboration, field and laboratory methods, data analysis, and modeling, two graduate students worked with teachers to develop, implement, and disseminate standards-based lesson plans for student activities linking this research to learning objectives for middle school science.", "east": -0.4, "geometry": "POINT(-7.45 -73.3)", "instruments": null, "is_usap_dc": true, "keywords": "Nunataks; GLACIAL LANDFORMS/PROCESSES; Geochronology; GLACIATION; GLACIERS/ICE SHEETS; GLACIER THICKNESS/ICE SHEET THICKNESS; GLACIAL LANDFORMS; Dronning Maud Land", "locations": "Dronning Maud Land", "north": -71.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Lifton, Nathaniel; Harbor, Jonathan", "platforms": null, "repo": "ICE-D: Antarctica", "repositories": "Hammer Research Repository; ICE-D: Antarctica; Purdue University Research Repository", "science_programs": null, "south": -75.1, "title": "Mapping, Measuring and Modeling Geomorphology and Ice Change in Dronning Maud Land, Antarctica", "uid": "p0010562", "west": -14.5}, {"awards": "2332108 Loewy, Staci", "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))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 27 Feb 2025 00:00:00 GMT", "description": "Technical Abstract This research evaluates whether the small Coats Land crustal block of East Antarctica is a tectonic tracer linking Kalahari and southern Laurentia within the Neoproterozoic supercontinent of Rodinia across an orogenic suture. A Pan-African (~600 Ma) suture separates the small Coats Land block from the main Mawson Craton indicating that this crustal block had an independent pre-Pan-African history. Existing data from the miniscule outcrops of bedrock in Coats Land provide critical clues to that paleogeography, suggesting that Laurentia collided with Kalahari across the Grenville-Namaqua/Natal-Maud orogen. The Coats Land block has only three small groups of bedrock exposures, two form nunataks and the third occurs in a cliff face. The two nunataks comprise granophyre and rhyolite contemporaneous with the ca. 1.1 Ga Keweenawan, mid-continent rift, volcanics of Laurentia and its proposed southwestern extension in El Paso, TX. Moreover, the Pb isotopes of the Coats Land and Keweenawan rocks are identical, and paleomagnetic data are broadly supportive of the Coats Land block having been located adjacent to the present southern margin of the Laurentian craton. Metamorphic rocks from the cliff face exposure lithologically resemble basement rocks of the El Paso, TX. The proposed research will further existing geochemical and geochronologic studies of specimens previously collected from Coats Land and new and existing samples of rocks collected near El Paso, Texas for detailed comparison. Analyses include zircon U-Pb dating and Hf and O isotope analysis, and whole rock geochemistry and Pb, Sm-Nd and Rb-Sr isotope analysis. This research will make maximum use of existing material from this extremely remote part of Antarctica to test this hypothesis. Researchers will collaborate with 2 well-established education-outreach programs in the Jackson School of Geosciences at The University of Texas at Austin. Undergraduate research assistants will be recruited from the Jackson Scholars Program (JSP). Researchers will provide a field- and lab-based seminar on reconstructing Rodinia for the JSP and will conduct research with high school students during GeoFORCE 12th grade summer academy. Non-technical Abstract This research evaluates whether the small Coats Land crustal block of East Antarctica is a piece of ancestral North America (Laurentia) that was transferred to southern Africa (Kalahari) during ~ 1 Ga collision, and subsequent breakup, of the two continents during the formation of the ancient supercontinent of Rodinia. Coats Land is separated from the adjacent Mawson Craton of Antarctica by ~600 Ma continental sutures indicating that Coats Land had an independent history prior to 600 Ma. Existing data from the miniscule outcrops of bedrock in Coats Land provide critical clues to that paleogeography, suggesting that Laurentia collided with Kalahari. The Coats Land block has only three small groups of bedrock exposures, two form nunataks and the third occurs in a cliff face. The two nunataks comprise granophyre and rhyolite contemporaneous with the ca. 1.1 Ga Keweenawan, mid-continent rift, volcanics of Laurentia and its proposed southwestern extension in El Paso, TX. Moreover, the Pb isotopes of the Coats Land and Keweenawan rocks are identical, and paleomagnetic data are broadly supportive of the Coats Land block having been located adjacent to the present southern margin of the Laurentian craton. Metamorphic rocks from the cliff face exposure lithologically resemble basement rocks of the El Paso, TX. The proposed research will further existing geochemical and geochronologic studies of specimens previously collected from Coats Land and new and existing samples of rocks collected near El Paso, Texas for detailed comparison. Analyses include zircon U-Pb dating and Hf and O isotope analysis, and whole rock geochemistry and Pb, Sm-Nd and Rb-Sr isotope analysis. This research will make maximum use of existing material from this extremely remote part of Antarctica to test this hypothesis. Researchers will collaborate with 2 well-established education-outreach programs in the Jackson School of Geosciences at The University of Texas at Austin. Undergraduate research assistants will be recruited from the Jackson Scholars Program (JSP). Researchers will provide a field- and lab-based seminar on reconstructing Rodinia for the JSP and will conduct research with high school students during GeoFORCE 12th grade summer academy. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Coats Land; Geochronology; ISOTOPES; Rodina; zircons; Paleogeography; Isotopes; PLATE TECTONICS; Texas", "locations": "Coats Land; Texas; Rodina", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Loewy, Staci; Dalziel, Ian W.", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Antarctica within Rodinia: Testing the Laurentia Connection", "uid": "p0010500", "west": -180.0}, {"awards": "2423761 Blackburn, Terrence", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Evaporitic carbonate crust isotopic data; Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "datasets": [{"dataset_uid": "601918", "doi": "10.15784/601918", "keywords": "Antarctica; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Subglacial", "people": "Piccione, Gavin", "repository": "USAP-DC", "science_program": null, "title": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "url": "https://www.usap-dc.org/view/dataset/601918"}, {"dataset_uid": "602030", "doi": "10.15784/602030", "keywords": "Antarctica; Cryosphere", "people": "Brigham, Noah", "repository": "USAP-DC", "science_program": null, "title": "Evaporitic carbonate crust isotopic data", "url": "https://www.usap-dc.org/view/dataset/602030"}], "date_created": "Tue, 14 May 2024 00:00:00 GMT", "description": "Non-technical abstract Earth\u2019s climatic changes have been recorded in the ice core collected from the Antarctic ice sheet. While these records provide a high resolution view of how polar temperatures changed through time, it is not always clear what Earth process influence Antarctic climate. One likely contributor to Antarctic temperature changes is the cyclic changes in Earth\u2019s orientation as it orbits the sun. These so-called Milankovitch cycles control the amount and pattern of sunlight reaching the polar regions, that in turn result in periods of climatic warming or cooling. While the orbital variations and control on incoming solar energy remain well understood, how they influence Antarctic climate remains unresolved. It is the goal of this project to determine how variations in Earth\u2019s orbit may be locally influencing Antarctic temperatures. The researchers on this project are pursing this goal by identifying periods of past ice melting on the surface of Antarctica using minerals that precipitate from the meltwaters that resulted from past warm periods. The timing of this past melting will be determined by radioisotopic dating of the minerals using the natural radioactive decay of uranium to thorium. By dating numerous samples, collected in past scientific expeditions throughout the Antarctic continent, these researchers aim to reconstruct the frequency and spatial pattern of past warming and in doing so, determine what aspect of Earth\u2019s orbital variations influences Antarctic ice loss. Technical abstract Antarctic ice cores provide high resolution records of Pleistocene Southern Hemisphere temperatures that show an overall coherence with Northern Hemisphere temperature variations. One explanation for this bi-hemispheric temperature covariance relies on changes in atmospheric CO2 that result from varying northern hemisphere insolation. An alternative posits that the apparent coherence of polar temperatures is due to the misleading covariance between northern hemisphere summer insolation and, the southern hemisphere summer duration. At present there is an insufficient understanding of the role that local insolation plays in Antarctic climate. The goal of this research project is to identify the temporal spatial patterns of solar forcing in Antarctica. To reach this goal, the project team will: 1) develop a way to identify periods of past surface melt production in Antarctica using U-Th dating of pedogenic carbonates; and 2) utilize the evidence of past surface melting to calibrate energy balance models and interrogate past Antarctic surface temperatures and; 3) compare the timing of Antarctic warm periods to potential solar forcing mechanisms such as peak summer insolation or summer duration. A means of identifying the spatial and temporal pattern at which local insolation influences Antarctic temperature would provide a transformative solution to the contradiction in current climate records. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; PALEOCLIMATE RECONSTRUCTIONS", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica", "uid": "p0010459", "west": -180.0}, {"awards": "2045611 Rasbury, Emma; 2042495 Blackburn, Terrence", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": " Subglacial Precipitates Record Antarctic Ice Sheet Response to Pleistocene Millennial Climate Cycles; Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ; Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps; U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "601911", "doi": "10.15784/601911", "keywords": "Antarctica; Cryosphere", "people": "Gagliardi, Jessica", "repository": "USAP-DC", "science_program": null, "title": "Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ", "url": "https://www.usap-dc.org/view/dataset/601911"}, {"dataset_uid": "601918", "doi": "10.15784/601918", "keywords": "Antarctica; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Subglacial", "people": "Piccione, Gavin", "repository": "USAP-DC", "science_program": null, "title": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "url": "https://www.usap-dc.org/view/dataset/601918"}, {"dataset_uid": "601594", "doi": "10.15784/601594", "keywords": "Antarctica; East Antarctica", "people": "Blackburn, Terrence; Piccione, Gavin", "repository": "USAP-DC", "science_program": null, "title": " Subglacial Precipitates Record Antarctic Ice Sheet Response to Pleistocene Millennial Climate Cycles", "url": "https://www.usap-dc.org/view/dataset/601594"}, {"dataset_uid": "601806", "doi": "10.15784/601806", "keywords": "Antarctica; Cryosphere; Erosion; Isotope Data; Major Elements; Soil; Taylor Glacier; Taylor Valley", "people": "Piccione, Gavin; Edwards, Graham; Blackburn, Terrence; Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601806"}], "date_created": "Fri, 18 Jun 2021 00:00:00 GMT", "description": "Over the past century, climate science has constructed an extensive record of Earth\u2019s ice age cycles through the chemical and isotopic characterization of various geologic archives such as polar ice cores, deep-ocean sediments, and cave speleothems. These climatic archives provide an insightful picture of ice age cycles and of the related large global sea level fluctuations triggered by these significant climate rhythms. However, such records still provide limited insight as to how or which of Earth\u2019s ice sheets contributed to higher sea levels during past warm climate periods. This is of particular importance for our modern world: the Antarctic ice sheet is currently the world\u2019s largest freshwater reservoir, which, if completely melted, would raise the global sea level by over 60 meters (200 feet). Yet, geologic records of Antarctic ice sheet sensitivity to warm climates are particularly limited and difficult to obtain, because the direct records of ice sheet geometry smaller than the modern one are still buried beneath the mile-thick ice covering the continent. Therefore, it remains unclear how much this ice sheet contributed to past sea level rise during warm climate periods or how it will respond to the anticipated near-future climate warming. In the proposed research we seek to develop sub-ice chemical precipitates\u2014minerals that form in lakes found beneath the ice sheet\u2014as a climatic archive, one that records how the Antarctic ice sheet responded to past climatic change. These sub-ice mineral formations accumulated beneath the ice for over a hundred thousand years, recording the changes in chemical and isotopic subglacial properties that occur in response to climate change. Eventually these samples were eroded by the ice sheet and moved to the Antarctic ice margin where they were collected and made available to study. This research will utilize advanced geochemical, isotopic and geochronologic techniques to develop record of the Antarctica ice sheet\u2019s past response to warm climate periods, directly informing efforts to understand how Antarctica will response to future warming. Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth\u2019s past warm periods. Large uncertainties, however, in reconstructions of past and future sea levels, result from the poorly constrained climate sensitivity of the Antarctic Ice sheet (AIS). This research project aims to develop the use of subglacial precipitates as an archive the Antarctic ice sheet (AIS) past response to climate change. The subglacial precipitates from East Antarctica form in water bodies beneath Antarctic ice and in doing so provide an entirely new and unique measure of how the AIS responds to climate change. In preliminary examination of these precipitates, we identified multiple samples consisting of cyclic opal and calcite that spans hundreds of thousands of years in duration. Our preliminary geochemical characterization of these samples indicates that the observed mineralogic changes result from a cyclic change in subglacial water compositions between isotopically and chemically distinct waters. Opal-forming waters are reduced (Ce* \u003c1 and high Fe/Mn) and exhibit elevated 234U/238U compositions similar to the saline groundwater brines found at the periphery of the AIS. Calcite-forming waters, are rather, oxidized and exhibit \u03b418O compositions consistent with derivation from the depleted polar plateau (\u003c -50 \u2030). 234U-230Th dates permit construction of a robust timeseries describing these mineralogic and compositional changes through time. Comparisons of these time series with other Antarctic climate records (e.g., ice core records) reveal that calcite forming events align with millennial scale changes in local temperature or \u201cAntarctic isotopic maximums\u201d, which represent Southern Hemisphere warm periods resulting in increased Atlantic Meridional overturing circulation. Ultimately, this project seeks to develop a comprehensive model as to how changes in the thermohaline cycle induce a glaciologic response which in turn induces a change in the composition of subglacial waters and the mineralogic phase recorded within the precipitate archive. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; FIELD INVESTIGATION; AMD; USA/NSF; Amd/Us; USAP-DC; East Antarctica", "locations": "East Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence; Tulaczyk, Slawek; Hain, Mathis; Rasbury, Troy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "uid": "p0010192", "west": -180.0}, {"awards": "2317097 Venturelli, Ryan; 1738989 Venturelli, Ryan", "bounds_geometry": "POLYGON((-114 -74,-112.2 -74,-110.4 -74,-108.6 -74,-106.8 -74,-105 -74,-103.2 -74,-101.4 -74,-99.6 -74,-97.8 -74,-96 -74,-96 -74.2,-96 -74.4,-96 -74.6,-96 -74.8,-96 -75,-96 -75.2,-96 -75.4,-96 -75.6,-96 -75.8,-96 -76,-97.8 -76,-99.6 -76,-101.4 -76,-103.2 -76,-105 -76,-106.8 -76,-108.6 -76,-110.4 -76,-112.2 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))", "dataset_titles": "200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica; Beryllium-10 exposure ages for Pope Glacier from a scoria cone 1.5 km west of Mount Murphy in the Amundsen Sea Embayment; Cosmogenic 10Be data and calculated surface exposure ages for 41 cobbles and boulders collected from nunataks adjacent to Larter and Lucchitta glaciers in the Hudson Mountains, West Antarctica; Cosmogenic Be-10 and Al-26 data and calculated surface exposure ages for cobbles collected from a moraine adjacent to Mount Murphy, West Antarctica; Cosmogenic Be-10 data and calculated surface exposure ages from nunataks adjacent to Pine Island Glacier in the Hudson Mountains, West Antarctica; Cosmogenic in situ 14C data and calculated surface exposure ages for 9 erratic cobbles collected from Mount Murphy, West Antarctica; Cosmogenic-Nuclide data at ICE-D; Firn and Ice Density at Winkie Nunatak; Geochronological data from the Hudson Mountains, Antarctica; Geomorphological measurements and lithological classifications of 90 erratic cobbles from the Hudson Mountains, West Antarctica; Ground-penetrating radar surveys at three nunataks in the Hudson Mountains in the Amundsen Sea sector of West Antarctica, December 2019; Ice-penetrating radar data from the northern embayment of the Mt. Murphy massif; Ice-penetrating radar data from the Thwaites Glacier grounding zone; In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers; Laboratory spectral reflectance measurements at VNIR-SWIR wavelengths of 17 rock samples from Mount Murphy, West Antarctica; NBP1902 Expedition data; Orientations of bedrock striations in the Hudson Mountains, West Antarctica; Pine Island Bay Relative Sea-Level Data", "datasets": [{"dataset_uid": "200295", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic-Nuclide data at ICE-D", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601705", "doi": "10.15784/601705", "keywords": "Antarctica; Cosmogenic Radionuclides; Mount Murphy; Subglacial Bedrock", "people": "Goehring, Brent; Balco, Gregory; Venturelli, Ryan", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers", "url": "https://www.usap-dc.org/view/dataset/601705"}, {"dataset_uid": "200083", "doi": "10.7284/908147", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1902 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1902"}, {"dataset_uid": "601860", "doi": "10.15784/601860", "keywords": "Antarctica; Cryosphere; Grounding Zone; Ice Penetrating Radar; Thwaites Glacier", "people": "Campbell, Seth; Goehring, Brent; Balco, Gregory", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Ice-penetrating radar data from the Thwaites Glacier grounding zone", "url": "https://www.usap-dc.org/view/dataset/601860"}, {"dataset_uid": "601554", "doi": "10.15784/601554", "keywords": "Antarctica; Pine Island Bay; Radiocarbon; Raised Beaches", "people": "Braddock, Scott; Hall, Brenda", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Pine Island Bay Relative Sea-Level Data", "url": "https://www.usap-dc.org/view/dataset/601554"}, {"dataset_uid": "601838", "doi": "10.15784/601838", "keywords": "Antarctica; Cryosphere; Density; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Density; Ice Core Records; Snow/ice; Snow/Ice", "people": "Venturelli, Ryan", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Firn and Ice Density at Winkie Nunatak", "url": "https://www.usap-dc.org/view/dataset/601838"}, {"dataset_uid": "601834", "doi": "10.15784/601834", "keywords": "Antarctica; Cryosphere; Mount Murphy", "people": "Campbell, Seth; Balco, Gregory; Goehring, Brent", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Ice-penetrating radar data from the northern embayment of the Mt. Murphy massif", "url": "https://www.usap-dc.org/view/dataset/601834"}, {"dataset_uid": "200483", "doi": "10.5285/de4a62bc-9c01-4aa3-9fd8-c64d706cfc13", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Cosmogenic 10Be data and calculated surface exposure ages for 41 cobbles and boulders collected from nunataks adjacent to Larter and Lucchitta glaciers in the Hudson Mountains, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/02025"}, {"dataset_uid": "200484", "doi": "10.5285/8f999423-ff40-4181-bdf3-964a7e145772", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Geochronological data from the Hudson Mountains, Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/02044"}, {"dataset_uid": "200485", "doi": "10.5285/fcd80bf1-bd69-4054-826c-a4727af8096a", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Laboratory spectral reflectance measurements at VNIR-SWIR wavelengths of 17 rock samples from Mount Murphy, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01918"}, {"dataset_uid": "200486", "doi": "10.5285/dbb30962-bbf3-434a-9f27-6de2f61a86e2", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Cosmogenic in situ 14C data and calculated surface exposure ages for 9 erratic cobbles collected from Mount Murphy, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01925"}, {"dataset_uid": "200487", "doi": "10.5285/7e80c81b-acc2-4a9b-9b5e-d37d49705524", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Orientations of bedrock striations in the Hudson Mountains, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01868"}, {"dataset_uid": "200488", "doi": "10.5285/79c8eb39-5c19-440e-804f-816cd0b8e4bd", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Geomorphological measurements and lithological classifications of 90 erratic cobbles from the Hudson Mountains, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01867"}, {"dataset_uid": "200489", "doi": "10.5285/1efc0048-5f0f-4ae7-a3a6-7728fe2ccf48", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Cosmogenic Be-10 and Al-26 data and calculated surface exposure ages for cobbles collected from a moraine adjacent to Mount Murphy, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01840"}, {"dataset_uid": "200490", "doi": "10.5285/9555694e-c9f5-4bf8-a556-2ad9d29e55c6", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Ground-penetrating radar surveys at three nunataks in the Hudson Mountains in the Amundsen Sea sector of West Antarctica, December 2019", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01842"}, {"dataset_uid": "200491", "doi": "10.5285/9ddd50c8-cd08-4afe-b245-f6891f1d9a3f", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Cosmogenic Be-10 data and calculated surface exposure ages from nunataks adjacent to Pine Island Glacier in the Hudson Mountains, West Antarctica", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01759"}, {"dataset_uid": "200492", "doi": "10.5285/8f275626-5f22-48df-95e5-cdc8f204a897", "keywords": null, "people": null, "repository": "NERC EDS UK Polar Data Center", "science_program": null, "title": "Beryllium-10 exposure ages for Pope Glacier from a scoria cone 1.5 km west of Mount Murphy in the Amundsen Sea Embayment", "url": "https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01661"}, {"dataset_uid": "601677", "doi": "10.15784/601677", "keywords": "Antarctica; Ice Penetrating Radar; Pine Island Glacier; Subglacial Bedrock", "people": "Braddock, Scott", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "200 MHz ground-penetrating radar from Winkie Nunatak, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601677"}], "date_created": "Tue, 16 Mar 2021 00:00:00 GMT", "description": "This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. The Thwaites Glacier system dominates the contribution to sea-level rise from Antarctica. Predicting how this system will evolve in coming decades, and thereby its likely contribution to sea level, requires detailed understanding of how it has responded to changes in climate and oceanographic conditions in the past. This project will provide a record of regional sea-level change by establishing chronologies for raised marine beaches as well as the timing and duration of periods of retreat of Thwaites Glacier during the past 10,000 years by sampling and dating bedrock presently covered by Thwaites Glacier via subglacial drilling. Together with climatic and oceanographic conditions from other records, these will provide boundary conditions for past-to-present model simulations as well as those used to predict future glacier changes under a range of climate scenarios. Specifically, the project will test the hypothesis--implied by existing geological evidence from the region--that present rapid retreat of the Thwaites Glacier system is reversible. The team aims to utilize two approaches: 1. To reconstruct relative sea level during the Holocene, it will map and date raised marine and shoreline deposits throughout Pine Island Bay. Chronological constraints on sea-level change will be provided by radiocarbon dating of organic material in landforms and sediments that are genetically related to past sea level, such as shell fragments, bones of marine fauna, and penguin guano. 2. To obtain geological evidence for past episodes of grounding-line retreat, the team will apply cosmogenic-nuclide exposure-dating of subglacial bedrock. Using drill systems recently developed for subglacial bedrock recovery, the team will obtain subglacial bedrock from sites where ice thickness is dynamically linked to grounding-line position in the Thwaites system (specifically in the Hudson Mountains, and near Mount Murphy). Observation of significant cosmogenic-nuclide concentrations--the team will primarily measure Beryllium-10 and in situ Carbon-14--in these samples would provide direct, unambiguous evidence for past episodes of thinning linked to grounding-line retreat as well as constraints on their timing and duration. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -96.0, "geometry": "POINT(-105 -75)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; FIELD INVESTIGATION; GLACIERS/ICE SHEETS; GLACIAL LANDFORMS; LABORATORY; Amd/Us; USAP-DC; GLACIATION; Amundsen Sea; USA/NSF", "locations": "Amundsen Sea", "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Venturelli, Ryan A; Goehring, Brent; Hall, Brenda; Campbell, Seth; Balco, Gregory", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D; NERC EDS UK Polar Data Center; R2R; USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "uid": "p0010165", "west": -114.0}, {"awards": "1142162 Stone, John", "bounds_geometry": "POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))", "dataset_titles": "Cosmogenic nuclide data at ICE-D; Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "datasets": [{"dataset_uid": "200299", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data at ICE-D", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "600162", "doi": "10.15784/600162", "keywords": "Antarctica; Be-10; Chemistry:rock; Chemistry:Rock; Cosmogenic Dating; Glaciology; Nunataks; Sample/collection Description; Sample/Collection Description; Solid Earth; Whitmore Mountains", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "url": "https://www.usap-dc.org/view/dataset/600162"}], "date_created": "Wed, 16 Mar 2016 00:00:00 GMT", "description": "1142162/Stone This award supports a project to conduct a reconnaissance geological and radar-sounding study of promising sites in West Antarctica as a prelude to a future project to conduct subglacial cosmogenic nuclide measurements. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain meter-scale surface detail, using synthetic aperture techniques. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public.", "east": -85.14, "geometry": "POINT(-94.64 -81.755)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; Antarctica; ICE SHEETS", "locations": "Antarctica", "north": -81.07, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John; Conway, Howard; Winebrenner, Dale", "platforms": "Not provided", "repo": "ICE-D", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -82.44, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "uid": "p0000335", "west": -104.14}]

View results on map Help on results map