USAP-DC

{"dp_type": "Dataset", "free_text": "Trace Elements"}

[{"awards": "1841228 Lyons, W. Berry", "bounds_geometry": ["POINT(163.5074 -77.5789)"], "date_created": "Mon, 28 Oct 2024 00:00:00 GMT", "description": "This dataset includes aqueous chemistry of water from the hyporheic zone in Wales Stream, Taylor Valley, Antarctica, just upstream from New Harbor Camp. Data includes major ions, nutrients, trace elements, stable iron isotopes, and stable isotopes of water.", "east": 163.5074, "geometry": ["POINT(163.5074 -77.5789)"], "keywords": "Antarctica; Cryosphere; Nutrients; Stable Isotopes; Taylor Valley; Trace Elements", "locations": "Taylor Valley; Antarctica", "north": -77.5789, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Gardner, Christopher B.", "project_titles": "Fe Behavior and Bioavailability in Sub-aerial Runoff into the Ross Sea", "projects": [{"proj_uid": "p0010483", "repository": "USAP-DC", "title": "Fe Behavior and Bioavailability in Sub-aerial Runoff into the Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5789, "title": "Hyporheic zone geochemistry of Wales Stream, Taylor Valley, Antarctica", "uid": "601847", "west": 163.5074}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Wed, 01 Feb 2023 00:00:00 GMT", "description": "This dataset contains water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (\u03b42H and \u03b418O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "locations": "West Antarctic Ice Sheet; Antarctica; Mercer Subglacial Lake; Mercer Subglacial Lake", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "uid": "601663", "west": -149.50134}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": ["POINT(-42.933 -61.849)"], "date_created": "Wed, 22 Jun 2022 00:00:00 GMT", "description": "This dataset contains measurements of major and trace elements on 190 samples of Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. The composition of detrital, biogenic and authigenic sediment components was assessed via whole rock geochemistry of sediment samples. Instrument analysis was completed at Montclair State University.", "east": -42.933, "geometry": ["POINT(-42.933 -61.849)"], "keywords": "Antarctica; Glaciation; IODP 650; IODP 696; Paleoceanography; Provenance; Sediment Core Data; Weathering; Weddell Sea", "locations": "Antarctica; Weddell Sea", "north": -61.849, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Hojnacki, Victoria; Li, Xiaona; States, Abbey; Lepp, Allison", "project_titles": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "projects": [{"proj_uid": "p0010101", "repository": "USAP-DC", "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.849, "title": "Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent", "uid": "601582", "west": -42.933}, {"awards": "1643494 Saal, Alberto", "bounds_geometry": ["POLYGON((-68.074 -57.345,-66.6033 -57.345,-65.1326 -57.345,-63.6619 -57.345,-62.1912 -57.345,-60.7205 -57.345,-59.2498 -57.345,-57.7791 -57.345,-56.3084 -57.345,-54.8377 -57.345,-53.367 -57.345,-53.367 -58.1252,-53.367 -58.9054,-53.367 -59.6856,-53.367 -60.4658,-53.367 -61.246,-53.367 -62.0262,-53.367 -62.8064,-53.367 -63.5866,-53.367 -64.3668,-53.367 -65.147,-54.8377 -65.147,-56.3084 -65.147,-57.7791 -65.147,-59.2498 -65.147,-60.7205 -65.147,-62.1912 -65.147,-63.6619 -65.147,-65.1326 -65.147,-66.6033 -65.147,-68.074 -65.147,-68.074 -64.3668,-68.074 -63.5866,-68.074 -62.8064,-68.074 -62.0262,-68.074 -61.246,-68.074 -60.4658,-68.074 -59.6856,-68.074 -58.9054,-68.074 -58.1252,-68.074 -57.345))"], "date_created": "Mon, 07 Feb 2022 00:00:00 GMT", "description": "", "east": -53.367, "geometry": ["POINT(-60.7205 -61.246)"], "keywords": "Antarctica; Antarctic Peninsula; Chemical Composition; Chemistry:rock; Chemistry:Rock; Geochemistry; Isotope Data; Trace Elements", "locations": "Antarctic Peninsula; Antarctica", "north": -57.345, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Saal, Alberto", "project_titles": "Magmatic Volatiles, Unraveling the Reservoirs and Processes of the Volcanism in the Antarctic Peninsula", "projects": [{"proj_uid": "p0010196", "repository": "USAP-DC", "title": "Magmatic Volatiles, Unraveling the Reservoirs and Processes of the Volcanism in the Antarctic Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.147, "title": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "uid": "601519", "west": -68.074}, {"awards": "1738942 Wellner, Julia", "bounds_geometry": ["POLYGON((-107.38 -74.64,-107.065 -74.64,-106.75 -74.64,-106.435 -74.64,-106.12 -74.64,-105.805 -74.64,-105.49 -74.64,-105.175 -74.64,-104.86 -74.64,-104.545 -74.64,-104.23 -74.64,-104.23 -74.683,-104.23 -74.726,-104.23 -74.769,-104.23 -74.812,-104.23 -74.855,-104.23 -74.898,-104.23 -74.941,-104.23 -74.984,-104.23 -75.027,-104.23 -75.07,-104.545 -75.07,-104.86 -75.07,-105.175 -75.07,-105.49 -75.07,-105.805 -75.07,-106.12 -75.07,-106.435 -75.07,-106.75 -75.07,-107.065 -75.07,-107.38 -75.07,-107.38 -75.027,-107.38 -74.984,-107.38 -74.941,-107.38 -74.898,-107.38 -74.855,-107.38 -74.812,-107.38 -74.769,-107.38 -74.726,-107.38 -74.683,-107.38 -74.64))"], "date_created": "Thu, 27 Jan 2022 00:00:00 GMT", "description": "This dataset contains measurements from grain-size, x-ray fluorescence (XRF), and physical properties (including magnetic susceptibility, water content, and shear strength) analyses of five sediment cores collected offshore Thwaites Glacier during cruises NBP19-02 (cores KC04, KC08, and KC23) and NBP20-02 (cores KC33 and KC67). We estimate the cores, which are between 213.5 and 297.5 cm in length, reflect deposition during the last ~10 kyr, consistent with published constraints of deglaciation of this region. Data are organized in Microsoft Excel spreadsheets and core locations are provided in a PDF.", "east": -104.23, "geometry": ["POINT(-105.805 -74.855)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Glaciomarine Sediment; Grain Size; Magnetic Susceptibility; Marine Geoscience; Marine Sediments; NBP1902; NBP2002; Physical Properties; R/v Nathaniel B. Palmer; Sediment Core Data; Thwaites Glacier; Trace Elements; XRF", "locations": "Antarctica; Thwaites Glacier", "north": -74.64, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Lepp, Allison", "project_titles": "NSF-NERC: THwaites Offshore Research (THOR)", "projects": [{"proj_uid": "p0010062", "repository": "USAP-DC", "title": "NSF-NERC: THwaites Offshore Research (THOR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.07, "title": "Physical and geochemical data from five sediment cores collected offshore Thwaites Glacier", "uid": "601514", "west": -107.38}, {"awards": "1341494 Gao, Yuan", "bounds_geometry": ["POINT(64 64)"], "date_created": "Mon, 24 Aug 2020 00:00:00 GMT", "description": "The dataset includes the concentrations and particle size distributions of aerosol trace elements (TEs) through the sampling of size-segregated aerosol particles made at Palmer Station, Antarctic Peninsula, which took place in the austral summer of 2016-2017. The estimated dry deposition fluxes of these elements were derived from these new results.", "east": 64.0, "geometry": ["POINT(64 64)"], "keywords": "Antarctica; Antarctic Peninsula; Palmer Station; Trace Elements", "locations": "Palmer Station; Antarctica; Palmer Station; Antarctic Peninsula", "north": 64.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Gao, Yuan", "project_titles": "Quantifying Atmospheric Iron Properties over West Antarctic Peninsula", "projects": [{"proj_uid": "p0010082", "repository": "USAP-DC", "title": "Quantifying Atmospheric Iron Properties over West Antarctic Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": 64.0, "title": "Concentrations and Particle Size Distributions of Aerosol Trace Elements", "uid": "601370", "west": 64.0}, {"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": "1144176 Lyons, W. Berry", "bounds_geometry": ["POLYGON((162.250099 -77.719928,162.2519358 -77.719928,162.2537726 -77.719928,162.2556094 -77.719928,162.2574462 -77.719928,162.259283 -77.719928,162.2611198 -77.719928,162.2629566 -77.719928,162.2647934 -77.719928,162.2666302 -77.719928,162.268467 -77.719928,162.268467 -77.7201251,162.268467 -77.7203222,162.268467 -77.7205193,162.268467 -77.7207164,162.268467 -77.7209135,162.268467 -77.7211106,162.268467 -77.7213077,162.268467 -77.7215048,162.268467 -77.7217019,162.268467 -77.721899,162.2666302 -77.721899,162.2647934 -77.721899,162.2629566 -77.721899,162.2611198 -77.721899,162.259283 -77.721899,162.2574462 -77.721899,162.2556094 -77.721899,162.2537726 -77.721899,162.2519358 -77.721899,162.250099 -77.721899,162.250099 -77.7217019,162.250099 -77.7215048,162.250099 -77.7213077,162.250099 -77.7211106,162.250099 -77.7209135,162.250099 -77.7207164,162.250099 -77.7205193,162.250099 -77.7203222,162.250099 -77.7201251,162.250099 -77.719928))"], "date_created": "Tue, 07 May 2019 00:00:00 GMT", "description": "Blood Falls is a hypersaline, iron\u2010rich discharge at the terminus of the Taylor Glacier in the McMurdo Dry Valleys, Antarctica. In November 2014, brine in a conduit within the glacier was penetrated and sampled using clean\u2010entry techniques and a thermoelectric melting probe called the IceMole. We analyzed the englacial brine sample for filterable iron (fFe), total Fe, major cations and anions, nutrients, organic carbon, and perchlorate. In addition, aliquots were analyzed for minor and trace elements and isotopes including \u03b4D and \u03b418O of water, \u03b434S and \u03b418O of sulfate, 234U, 238U, \u03b411B, 87Sr/86Sr, and \u03b481Br. These measurements were made in order to (1) determine the source and geochemical evolution of the brine and (2) compare the chemistry of the brine to that of nearby hypersaline lake waters and previous supraglacially sampled collections of Blood Falls outflow that were interpreted as end\u2010member brines.", "east": 162.268467, "geometry": ["POINT(162.259283 -77.7209135)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Brine", "locations": "Antarctica", "north": -77.719928, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Lyons, W. Berry; Gardner, Christopher B.", "project_titles": "Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys", "projects": [{"proj_uid": "p0000002", "repository": "USAP-DC", "title": "Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.721899, "title": "The Geochemistry of englacial brine from Taylor Glacier, Antarctica.", "uid": "601179", "west": 162.250099}, {"awards": "0636740 Kreutz, Karl", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Mon, 01 Jun 2015 00:00:00 GMT", "description": "Measurements of a suite of trace elements in snow pit samples from WAIS Divide, Antarctica.", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Trace Elements; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "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": -79.28, "title": "Snowpit Chemistry - Methods Comparison, WAIS Divide, Antarctica", "uid": "609620", "west": -112.05}, {"awards": "9725057 Mayewski, Paul; 0837883 Mayewski, Paul", "bounds_geometry": ["POLYGON((-76.1 -77.68,-53.253 -77.68,-30.406 -77.68,-7.559 -77.68,15.288 -77.68,38.135 -77.68,60.982 -77.68,83.829 -77.68,106.676 -77.68,129.523 -77.68,152.37 -77.68,152.37 -78.912,152.37 -80.144,152.37 -81.376,152.37 -82.608,152.37 -83.84,152.37 -85.072,152.37 -86.304,152.37 -87.536,152.37 -88.768,152.37 -90,129.523 -90,106.676 -90,83.829 -90,60.982 -90,38.135 -90,15.288 -90,-7.559 -90,-30.406 -90,-53.253 -90,-76.1 -90,-76.1 -88.768,-76.1 -87.536,-76.1 -86.304,-76.1 -85.072,-76.1 -83.84,-76.1 -82.608,-76.1 -81.376,-76.1 -80.144,-76.1 -78.912,-76.1 -77.68))"], "date_created": "Thu, 11 Jul 2013 00:00:00 GMT", "description": "This data set contains sub-annually resolved ice core chemistry data from various sites on the Antarctic Ice Sheet during the US International Trans-Antarctic Scientific Expedition (US ITASE) deployments. Researchers conducted experiments approximately every 30 - 300 km looking for clues representing climatic conditions over the past 200-1000+ years. Ice cores obtained for the glaciochemical component of the US ITASE research were analyzed for soluble major ion content and in some cases trace elements. Extreme events, such as volcanic eruptions, provide absolute age horizons within each core that are easily identified in chemical profiles. Our chemical analysis is also useful for quantifying anthropogenic impact, biogeochemical cycling, and for reconstructing past atmospheric circulation patterns.", "east": 152.37, "geometry": ["POINT(38.135 -83.84)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; ITASE; Paleoclimate; Solid Earth; WAIS", "locations": "Antarctica; WAIS", "north": -77.68, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dixon, Daniel A.; Mayewski, Paul A.", "project_titles": "Science Management for the United States Component of the International Trans-Antarctic Expedition", "projects": [{"proj_uid": "p0000221", "repository": "USAP-DC", "title": "Science Management for the United States Component of the International Trans-Antarctic Expedition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": -90.0, "title": "US International Trans-Antarctic Scientific Expedition (US ITASE) Glaciochemical Data", "uid": "609273", "west": -76.1}, {"awards": "0636506 Mayewski, Paul", "bounds_geometry": ["POLYGON((-137.7 -75.7,-137.4 -75.7,-137.1 -75.7,-136.8 -75.7,-136.5 -75.7,-136.2 -75.7,-135.9 -75.7,-135.6 -75.7,-135.3 -75.7,-135 -75.7,-134.7 -75.7,-134.7 -75.773,-134.7 -75.846,-134.7 -75.919,-134.7 -75.992,-134.7 -76.065,-134.7 -76.138,-134.7 -76.211,-134.7 -76.284,-134.7 -76.357,-134.7 -76.43,-135 -76.43,-135.3 -76.43,-135.6 -76.43,-135.9 -76.43,-136.2 -76.43,-136.5 -76.43,-136.8 -76.43,-137.1 -76.43,-137.4 -76.43,-137.7 -76.43,-137.7 -76.357,-137.7 -76.284,-137.7 -76.211,-137.7 -76.138,-137.7 -76.065,-137.7 -75.992,-137.7 -75.919,-137.7 -75.846,-137.7 -75.773,-137.7 -75.7))"], "date_created": "Thu, 29 Jul 2010 00:00:00 GMT", "description": "This data set contains measurments from co-registered samples from a horizontal trench in the Mt. Moulton Blue Ice Area (BIA) in Antarctica. All 3795 co-registered samples were analyzed for their soluble major anion content by Ion Chromatography (IC) and for trace elements by inductively coupled plasma sector field mass spectrometry . \n\nThe data are available via FTP in Microsoft Excel format (.xls) and Microsoft Word document (.doc).", "east": -134.7, "geometry": ["POINT(-136.2 -76.065)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mt Moulton; Paleoclimate", "locations": "Antarctica; Mt Moulton", "north": -75.7, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Mayewski, Paul A.; Korotkikh, Elena", "project_titles": "Collaborative Proposal: 2000+ Year Detailed, Calibrated Climate Reconstruction from a South Pole Ice Core Set in an Antarctic - Global Scale Context", "projects": [{"proj_uid": "p0000209", "repository": "USAP-DC", "title": "Collaborative Proposal: 2000+ Year Detailed, Calibrated Climate Reconstruction from a South Pole Ice Core Set in an Antarctic - Global Scale Context"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.43, "title": "Mt. Moulton Ice Trench Mass Spectrometry Data, Antarctica", "uid": "609472", "west": -137.7}, {"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}]

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