[{"awards": "2035580 Aarons, Sarah; 2019719 Brook, Edward", "bounds_geometry": ["POINT(159.31 -76.7)"], "date_created": "Wed, 29 Apr 2026 00:00:00 GMT", "description": "Previous analyses of dust concentration and size distribution in ice cores are limited to the past 800,000 years; however, the ALHIC1901 ice core drilled at the Allan Hills Blue Ice Area (BIA) in East Antarctica provides a unique opportunity to examine older discontinuous records of ice ranging in age from 4000-\u2013500 ka. Here we present a discrete record of insoluble particles within ALHIC1901 from the bottom 25 m of the core. We investigated the particle mass concentration, size distribution, and mineralogy within the core to assess the preservation of dust records in BIAs with complex flow histories. We find that the insoluble particle concentrations are likely altered by entrainment of basal sediment for depths 5 m above bedrock. For shallower depths less affected by subglacial input, the record lacks expected peaks in dust concentration during glacial periods, which have been termed \u201clong snapshots,\u201d implying that low net accumulation rates during glacial periods at the Allan Hills BIA results in the preferential loss or attenuation of glacial ice and a corresponding bias toward the preservation of interglacial ice. The dust concentrations may also be further smoothed due to ice thinning. A subset of particles from both the upper and lower ranges of depths analyzed shows evidence of mineral weathering and/or in situ production of secondary minerals, and insoluble particle concentration correlates well with non-atmospherically derived carbon dioxide concentrations. These results highlight the importance of identifying signs of basal ice-rock interactions and/or complicated accumulation and ablation histories as these affect our interpretation of paleoclimate records preserved in ice cores from BIAs.", "east": 159.31, "geometry": ["POINT(159.31 -76.7)"], "keywords": "Allan Hills; Antarctica; Basal Debris; Cryosphere; Dust; Ice Core; Ice Core Dust", "locations": "Antarctica; Allan Hills; Allan Hills", "north": -76.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Choi, Alissa; Carter, Austin; Marks-Peterson, Julia; Shackleton, Sarah; Higgins, John; Brook, Edward J.; Kirkpatrick, Liam; Chalif, Jacob; Aarons, Sarah", "project_titles": "Center for Oldest Ice Exploration; Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial", "projects": [{"proj_uid": "p0010270", "repository": "USAP-DC", "title": "Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial"}, {"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.7, "title": "Dust Record from Allan Hills Blue Ice: Towards Extending the Archive to 4000 ka", "uid": "602055", "west": 159.31}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Wed, 01 Feb 2023 00:00:00 GMT", "description": "This dataset contains bulk sediment properties measurements from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: physical properties (bulk density, mass water content, porosity, shear strength, particle size distribution, and mineralogy); carbon (inorganic and organic); iron (ascorbate- and dithionite-extractable); and sulfur (acid-volatile and chromium-reducible).", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; Physical Properties; SALSA; Sediment Core; Sulfur; West Antarctic Ice Sheet", "locations": "Mercer Subglacial Lake; Mercer Subglacial Lake; West Antarctic Ice Sheet; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "uid": "601661", "west": -149.50134}, {"awards": "1543344 Soreghan, Gerilyn", "bounds_geometry": ["POLYGON((162.322717 -77.417633,162.444362 -77.417633,162.566007 -77.417633,162.687652 -77.417633,162.80929700000002 -77.417633,162.93094200000002 -77.417633,163.052587 -77.417633,163.174232 -77.417633,163.295877 -77.417633,163.417522 -77.417633,163.539167 -77.417633,163.539167 -77.4501507,163.539167 -77.4826684,163.539167 -77.5151861,163.539167 -77.5477038,163.539167 -77.5802215,163.539167 -77.61273920000001,163.539167 -77.6452569,163.539167 -77.6777746,163.539167 -77.7102923,163.539167 -77.74281,163.417522 -77.74281,163.295877 -77.74281,163.174232 -77.74281,163.052587 -77.74281,162.93094200000002 -77.74281,162.80929700000002 -77.74281,162.687652 -77.74281,162.566007 -77.74281,162.444362 -77.74281,162.322717 -77.74281,162.322717 -77.7102923,162.322717 -77.6777746,162.322717 -77.6452569,162.322717 -77.61273920000001,162.322717 -77.5802215,162.322717 -77.5477038,162.322717 -77.5151861,162.322717 -77.4826684,162.322717 -77.4501507,162.322717 -77.417633))"], "date_created": "Tue, 16 Aug 2022 00:00:00 GMT", "description": "This data file contains locations and descriptions of the samples collected for the NSF project titled \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\". Data collected includes BET surface area, LPSA grain size, granulometry, mineralogy (XRD) and whole rock geochemistry (ICP-MS).", "east": 163.539167, "geometry": ["POINT(162.93094200000002 -77.5802215)"], "keywords": "Antarctica; Anza Borrego; Iceland; McMurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "locations": "Antarctica; Iceland; Peru; Norway; McMurdo Dry Valleys; Wright Valley; Taylor Valley; Antarctica; Anza Borrego; Puerto Rico; Washington", "north": -77.417633, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Demirel-Floyd, Cansu", "project_titles": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "projects": [{"proj_uid": "p0010181", "repository": "USAP-DC", "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.74281, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "uid": "601599", "west": 162.322717}]

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Dataset Title/Abstract/Map	NSF Award(s)	Date Created	PIs / Scientists	Project Links	Abstract	Bounds Geometry	Geometry	Selected	Visible
Dust Record from Allan Hills Blue Ice: Towards Extending the Archive to 4000 ka	2035580 2019719	2026-04-29	Choi, Alissa; Carter, Austin; Marks-Peterson, Julia; Shackleton, Sarah; Higgins, John; Brook, Edward J.; Kirkpatrick, Liam; Chalif, Jacob; Aarons, Sarah	Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial Center for Oldest Ice Exploration	Previous analyses of dust concentration and size distribution in ice cores are limited to the past 800,000 years; however, the ALHIC1901 ice core drilled at the Allan Hills Blue Ice Area (BIA) in East Antarctica provides a unique opportunity to examine older discontinuous records of ice ranging in age from 4000-–500 ka. Here we present a discrete record of insoluble particles within ALHIC1901 from the bottom 25 m of the core. We investigated the particle mass concentration, size distribution, and mineralogy within the core to assess the preservation of dust records in BIAs with complex flow histories. We find that the insoluble particle concentrations are likely altered by entrainment of basal sediment for depths 5 m above bedrock. For shallower depths less affected by subglacial input, the record lacks expected peaks in dust concentration during glacial periods, which have been termed “long snapshots,” implying that low net accumulation rates during glacial periods at the Allan Hills BIA results in the preferential loss or attenuation of glacial ice and a corresponding bias toward the preservation of interglacial ice. The dust concentrations may also be further smoothed due to ice thinning. A subset of particles from both the upper and lower ranges of depths analyzed shows evidence of mineral weathering and/or in situ production of secondary minerals, and insoluble particle concentration correlates well with non-atmospherically derived carbon dioxide concentrations. These results highlight the importance of identifying signs of basal ice-rock interactions and/or complicated accumulation and ablation histories as these affect our interpretation of paleoclimate records preserved in ice cores from BIAs.	["POINT(159.31 -76.7)"]	["POINT(159.31 -76.7)"]	false	false
Discrete bulk sediment properties data from Mercer Subglacial Lake	1543537	2023-02-01	Dore, John; Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA	Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments	This dataset contains bulk sediment properties measurements from cores collected from Mercer Subglacial Lake by the SALSA project. Included are: physical properties (bulk density, mass water content, porosity, shear strength, particle size distribution, and mineralogy); carbon (inorganic and organic); iron (ascorbate- and dithionite-extractable); and sulfur (acid-volatile and chromium-reducible).	["POINT(-149.50134 -84.640287)"]	["POINT(-149.50134 -84.640287)"]	false	false
Data and metadata for "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems"	1543344	2022-08-16	Demirel-Floyd, Cansu	Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems	This data file contains locations and descriptions of the samples collected for the NSF project titled "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems". Data collected includes BET surface area, LPSA grain size, granulometry, mineralogy (XRD) and whole rock geochemistry (ICP-MS).	["POLYGON((162.322717 -77.417633,162.444362 -77.417633,162.566007 -77.417633,162.687652 -77.417633,162.80929700000002 -77.417633,162.93094200000002 -77.417633,163.052587 -77.417633,163.174232 -77.417633,163.295877 -77.417633,163.417522 -77.417633,163.539167 -77.417633,163.539167 -77.4501507,163.539167 -77.4826684,163.539167 -77.5151861,163.539167 -77.5477038,163.539167 -77.5802215,163.539167 -77.61273920000001,163.539167 -77.6452569,163.539167 -77.6777746,163.539167 -77.7102923,163.539167 -77.74281,163.417522 -77.74281,163.295877 -77.74281,163.174232 -77.74281,163.052587 -77.74281,162.93094200000002 -77.74281,162.80929700000002 -77.74281,162.687652 -77.74281,162.566007 -77.74281,162.444362 -77.74281,162.322717 -77.74281,162.322717 -77.7102923,162.322717 -77.6777746,162.322717 -77.6452569,162.322717 -77.61273920000001,162.322717 -77.5802215,162.322717 -77.5477038,162.322717 -77.5151861,162.322717 -77.4826684,162.322717 -77.4501507,162.322717 -77.417633))"]	["POINT(162.93094200000002 -77.5802215)"]	false	false

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U.S. ANTARCTIC PROGRAM DATA CENTER

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