{"dp_type": "Dataset", "free_text": "Exposure age"}
[{"awards": "1643248 Hall, Brenda", "bounds_geometry": ["POLYGON((163 -78.2,163.05 -78.2,163.1 -78.2,163.15 -78.2,163.2 -78.2,163.25 -78.2,163.3 -78.2,163.35 -78.2,163.4 -78.2,163.45 -78.2,163.5 -78.2,163.5 -78.21000000000001,163.5 -78.22,163.5 -78.23,163.5 -78.24,163.5 -78.25,163.5 -78.26,163.5 -78.27,163.5 -78.28,163.5 -78.28999999999999,163.5 -78.3,163.45 -78.3,163.4 -78.3,163.35 -78.3,163.3 -78.3,163.25 -78.3,163.2 -78.3,163.15 -78.3,163.1 -78.3,163.05 -78.3,163 -78.3,163 -78.28999999999999,163 -78.28,163 -78.27,163 -78.26,163 -78.25,163 -78.24,163 -78.23,163 -78.22,163 -78.21000000000001,163 -78.2))"], "date_created": "Fri, 21 Oct 2022 00:00:00 GMT", "description": "This dataset includes beryllium-10 surface exposure data collected in conjunction with a glacial history project in the Walcott Bay region of southern McMurdo Sound. The data are presented in the conventional CRONUS input format.", "east": 163.5, "geometry": ["POINT(163.25 -78.25)"], "keywords": "Antarctica; Beryllium-10; Exposure Age; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; McMurdo Sound; Royal Society Range; Walcott Glacier", "locations": "Royal Society Range; McMurdo Sound; Royal Society Range; Walcott Glacier; Antarctica", "north": -78.2, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hall, Brenda", "project_titles": "Response of the Antarctic Ice Sheet to the last great global warming", "projects": [{"proj_uid": "p0010301", "repository": "USAP-DC", "title": "Response of the Antarctic Ice Sheet to the last great global warming"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.3, "title": "Walcott Glacier Exposure Data", "uid": "601616", "west": 163.0}, {"awards": "1341631 Lyons, W. Berry; 1341736 Adams, Byron", "bounds_geometry": ["POLYGON((-177.4099 -84.4661,-177.08229 -84.4661,-176.75468 -84.4661,-176.42707 -84.4661,-176.09946 -84.4661,-175.77185 -84.4661,-175.44424 -84.4661,-175.11663 -84.4661,-174.78902 -84.4661,-174.46141 -84.4661,-174.1338 -84.4661,-174.1338 -84.56828,-174.1338 -84.67046,-174.1338 -84.77264,-174.1338 -84.87482,-174.1338 -84.977,-174.1338 -85.07918,-174.1338 -85.18136,-174.1338 -85.28354,-174.1338 -85.38572,-174.1338 -85.4879,-174.46141 -85.4879,-174.78902 -85.4879,-175.11663 -85.4879,-175.44424 -85.4879,-175.77185 -85.4879,-176.09946 -85.4879,-176.42707 -85.4879,-176.75468 -85.4879,-177.08229 -85.4879,-177.4099 -85.4879,-177.4099 -85.38572,-177.4099 -85.28354,-177.4099 -85.18136,-177.4099 -85.07918,-177.4099 -84.977,-177.4099 -84.87482,-177.4099 -84.77264,-177.4099 -84.67046,-177.4099 -84.56828,-177.4099 -84.4661))"], "date_created": "Sun, 03 Jan 2021 00:00:00 GMT", "description": "We collected soil surface samples (n = 21) and depth profiles (n = 25) every 5 cm to refusal (up to 30 cm) from eleven ice-free areas along the Shackleton Glacier, a major outlet glacier of the East Antarctic Ice Sheet (EAIS). We measured meteoric 10Be concentrations, which were later used to estimate relative surface exposure ages of the soils from seven locations. ", "east": -174.1338, "geometry": ["POINT(-175.77185 -84.977)"], "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic Radionuclides; Geochemistry; Geomorphology; Shackleton Glacier; Surface Exposure Dates", "locations": "Antarctica; Shackleton Glacier", "north": -84.4661, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Diaz, Melisa A.", "project_titles": "Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains", "projects": [{"proj_uid": "p0010140", "repository": "USAP-DC", "title": "Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.4879, "title": "Meteoric 10Be data of soils from the Shackleton Glacier region", "uid": "601421", "west": -177.4099}, {"awards": "1443346 Stone, John", "bounds_geometry": ["POLYGON((-174 -84.5,-172.4 -84.5,-170.8 -84.5,-169.2 -84.5,-167.6 -84.5,-166 -84.5,-164.4 -84.5,-162.8 -84.5,-161.2 -84.5,-159.6 -84.5,-158 -84.5,-158 -84.63,-158 -84.76,-158 -84.89,-158 -85.02,-158 -85.15,-158 -85.28,-158 -85.41,-158 -85.54,-158 -85.67,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.67,-174 -85.54,-174 -85.41,-174 -85.28,-174 -85.15,-174 -85.02,-174 -84.89,-174 -84.76,-174 -84.63,-174 -84.5))"], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "This data set contains measurements of cosmic-ray-produced Be-10 in quartz from glacial erratics and bedrock at sites along and adjacent to Liv Glacier and Amundsen Glacier in the southern Transantarctic Mountains. Samples were collected during the 2016-17 and 2017-18 field seasons working from remote camps along the coast. Locations were determined by hand-held GPS. Elevations are based on barometric altimetry corrected for daily drift and referenced to precise (geodetic) GPS benchmarks established over a range of altitudes at each site. Horizon geometry and the resulting topographic shielding of the cosmic ray flux was determined from vertically-oriented full-sky (fisheye) photographs at each sample location. Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory using established procedures for mineral separation, dissolution, beryllium extraction and purification, described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Data are reported as input for the online CRONUS cosmogenic nuclide calculator (V3, current at the time of submission in November 2019). Exposure ages can be obtained by entering the data into the CRONUS calculator, at: http://hess.ess.washington.edu/math/v3/v3_age_in.html .\r\nData for each sample consists of two lines of input parameters, as follows:\t\t\t\t\t\t\t\t\t\r\n{Sample_name, Latitude (DD), Longitude (DD), Altitude (m asl), Scaling_function, Thickness (cm), Density (g/cm^3), Horizon_correction, Erosion_rate (cm/yr), Year_sampled}\r\n{Sample_name, Nuclide (in this case Be-10), Target_mineral (quartz), Be-10_concentration (atom/g), Error_Be-10_concentration (atom/g), Normalization}\r\nFurther information about the V3 input format is given at:\r\nhttp://hess.ess.washington.edu/math/docs/v3/v3_input_explained.html", "east": -158.0, "geometry": ["POINT(-166 -85.15)"], "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic; Cosmogenic Dating; Cosmogenic Radionuclides; Deglaciation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Liv Glacier; Rocks; Ross Ice Sheet; Surface Exposure Dates; Transantarctic Mountains", "locations": "Antarctica; Liv Glacier; Ross Ice Sheet; Transantarctic Mountains", "north": -84.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Stone, John", "project_titles": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "projects": [{"proj_uid": "p0010053", "repository": "USAP-DC", "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.8, "title": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast", "uid": "601226", "west": -174.0}, {"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": "0944475 Kaplan, Michael", "bounds_geometry": ["POLYGON((-180 -84.1,-176.97 -84.1,-173.94 -84.1,-170.91 -84.1,-167.88 -84.1,-164.85 -84.1,-161.82 -84.1,-158.79 -84.1,-155.76 -84.1,-152.73 -84.1,-149.7 -84.1,-149.7 -84.43,-149.7 -84.76,-149.7 -85.09,-149.7 -85.42,-149.7 -85.75,-149.7 -86.08,-149.7 -86.41,-149.7 -86.74,-149.7 -87.07,-149.7 -87.4,-152.73 -87.4,-155.76 -87.4,-158.79 -87.4,-161.82 -87.4,-164.85 -87.4,-167.88 -87.4,-170.91 -87.4,-173.94 -87.4,-176.97 -87.4,180 -87.4,178.12 -87.4,176.24 -87.4,174.36 -87.4,172.48 -87.4,170.6 -87.4,168.72 -87.4,166.84 -87.4,164.96 -87.4,163.08 -87.4,161.2 -87.4,161.2 -87.07,161.2 -86.74,161.2 -86.41,161.2 -86.08,161.2 -85.75,161.2 -85.42,161.2 -85.09,161.2 -84.76,161.2 -84.43,161.2 -84.1,163.08 -84.1,164.96 -84.1,166.84 -84.1,168.72 -84.1,170.6 -84.1,172.48 -84.1,174.36 -84.1,176.24 -84.1,178.12 -84.1,-180 -84.1))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica\u0027s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time.\nBroader Impact: The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": -149.7, "geometry": ["POINT(-174.25 -85.75)"], "keywords": "Antarctica; Cosmogenic Dating; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -84.1, "nsf_funding_programs": null, "persons": "Kaplan, Michael", "project_titles": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "projects": [{"proj_uid": "p0000459", "repository": "USAP-DC", "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "600115", "west": 161.2}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Walcott Glacier Exposure Data
|
1643248 |
2022-10-21 | Hall, Brenda |
Response of the Antarctic Ice Sheet to the last great global warming |
This dataset includes beryllium-10 surface exposure data collected in conjunction with a glacial history project in the Walcott Bay region of southern McMurdo Sound. The data are presented in the conventional CRONUS input format. | ["POLYGON((163 -78.2,163.05 -78.2,163.1 -78.2,163.15 -78.2,163.2 -78.2,163.25 -78.2,163.3 -78.2,163.35 -78.2,163.4 -78.2,163.45 -78.2,163.5 -78.2,163.5 -78.21000000000001,163.5 -78.22,163.5 -78.23,163.5 -78.24,163.5 -78.25,163.5 -78.26,163.5 -78.27,163.5 -78.28,163.5 -78.28999999999999,163.5 -78.3,163.45 -78.3,163.4 -78.3,163.35 -78.3,163.3 -78.3,163.25 -78.3,163.2 -78.3,163.15 -78.3,163.1 -78.3,163.05 -78.3,163 -78.3,163 -78.28999999999999,163 -78.28,163 -78.27,163 -78.26,163 -78.25,163 -78.24,163 -78.23,163 -78.22,163 -78.21000000000001,163 -78.2))"] | ["POINT(163.25 -78.25)"] | false | false |
Meteoric 10Be data of soils from the Shackleton Glacier region
|
1341631 1341736 |
2021-01-03 | Diaz, Melisa A. |
Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains |
We collected soil surface samples (n = 21) and depth profiles (n = 25) every 5 cm to refusal (up to 30 cm) from eleven ice-free areas along the Shackleton Glacier, a major outlet glacier of the East Antarctic Ice Sheet (EAIS). We measured meteoric 10Be concentrations, which were later used to estimate relative surface exposure ages of the soils from seven locations. | ["POLYGON((-177.4099 -84.4661,-177.08229 -84.4661,-176.75468 -84.4661,-176.42707 -84.4661,-176.09946 -84.4661,-175.77185 -84.4661,-175.44424 -84.4661,-175.11663 -84.4661,-174.78902 -84.4661,-174.46141 -84.4661,-174.1338 -84.4661,-174.1338 -84.56828,-174.1338 -84.67046,-174.1338 -84.77264,-174.1338 -84.87482,-174.1338 -84.977,-174.1338 -85.07918,-174.1338 -85.18136,-174.1338 -85.28354,-174.1338 -85.38572,-174.1338 -85.4879,-174.46141 -85.4879,-174.78902 -85.4879,-175.11663 -85.4879,-175.44424 -85.4879,-175.77185 -85.4879,-176.09946 -85.4879,-176.42707 -85.4879,-176.75468 -85.4879,-177.08229 -85.4879,-177.4099 -85.4879,-177.4099 -85.38572,-177.4099 -85.28354,-177.4099 -85.18136,-177.4099 -85.07918,-177.4099 -84.977,-177.4099 -84.87482,-177.4099 -84.77264,-177.4099 -84.67046,-177.4099 -84.56828,-177.4099 -84.4661))"] | ["POINT(-175.77185 -84.977)"] | false | false |
Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast
|
1443346 |
2019-11-21 | Stone, John |
Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment |
This data set contains measurements of cosmic-ray-produced Be-10 in quartz from glacial erratics and bedrock at sites along and adjacent to Liv Glacier and Amundsen Glacier in the southern Transantarctic Mountains. Samples were collected during the 2016-17 and 2017-18 field seasons working from remote camps along the coast. Locations were determined by hand-held GPS. Elevations are based on barometric altimetry corrected for daily drift and referenced to precise (geodetic) GPS benchmarks established over a range of altitudes at each site. Horizon geometry and the resulting topographic shielding of the cosmic ray flux was determined from vertically-oriented full-sky (fisheye) photographs at each sample location. Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory using established procedures for mineral separation, dissolution, beryllium extraction and purification, described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Data are reported as input for the online CRONUS cosmogenic nuclide calculator (V3, current at the time of submission in November 2019). Exposure ages can be obtained by entering the data into the CRONUS calculator, at: http://hess.ess.washington.edu/math/v3/v3_age_in.html . Data for each sample consists of two lines of input parameters, as follows: {Sample_name, Latitude (DD), Longitude (DD), Altitude (m asl), Scaling_function, Thickness (cm), Density (g/cm^3), Horizon_correction, Erosion_rate (cm/yr), Year_sampled} {Sample_name, Nuclide (in this case Be-10), Target_mineral (quartz), Be-10_concentration (atom/g), Error_Be-10_concentration (atom/g), Normalization} Further information about the V3 input format is given at: http://hess.ess.washington.edu/math/docs/v3/v3_input_explained.html | ["POLYGON((-174 -84.5,-172.4 -84.5,-170.8 -84.5,-169.2 -84.5,-167.6 -84.5,-166 -84.5,-164.4 -84.5,-162.8 -84.5,-161.2 -84.5,-159.6 -84.5,-158 -84.5,-158 -84.63,-158 -84.76,-158 -84.89,-158 -85.02,-158 -85.15,-158 -85.28,-158 -85.41,-158 -85.54,-158 -85.67,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.67,-174 -85.54,-174 -85.41,-174 -85.28,-174 -85.15,-174 -85.02,-174 -84.89,-174 -84.76,-174 -84.63,-174 -84.5))"] | ["POINT(-166 -85.15)"] | 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 |
Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines
|
0944475 |
2014-01-01 | Kaplan, Michael |
Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines |
Intellectual Merit: The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica's inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed <2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. Broader Impact: The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences. | ["POLYGON((-180 -84.1,-176.97 -84.1,-173.94 -84.1,-170.91 -84.1,-167.88 -84.1,-164.85 -84.1,-161.82 -84.1,-158.79 -84.1,-155.76 -84.1,-152.73 -84.1,-149.7 -84.1,-149.7 -84.43,-149.7 -84.76,-149.7 -85.09,-149.7 -85.42,-149.7 -85.75,-149.7 -86.08,-149.7 -86.41,-149.7 -86.74,-149.7 -87.07,-149.7 -87.4,-152.73 -87.4,-155.76 -87.4,-158.79 -87.4,-161.82 -87.4,-164.85 -87.4,-167.88 -87.4,-170.91 -87.4,-173.94 -87.4,-176.97 -87.4,180 -87.4,178.12 -87.4,176.24 -87.4,174.36 -87.4,172.48 -87.4,170.6 -87.4,168.72 -87.4,166.84 -87.4,164.96 -87.4,163.08 -87.4,161.2 -87.4,161.2 -87.07,161.2 -86.74,161.2 -86.41,161.2 -86.08,161.2 -85.75,161.2 -85.42,161.2 -85.09,161.2 -84.76,161.2 -84.43,161.2 -84.1,163.08 -84.1,164.96 -84.1,166.84 -84.1,168.72 -84.1,170.6 -84.1,172.48 -84.1,174.36 -84.1,176.24 -84.1,178.12 -84.1,-180 -84.1))"] | ["POINT(-174.25 -85.75)"] | false | false |