USAP-DC

{"dp_type": "Dataset", "free_text": "Otolith"}

[{"awards": "1947040 Postlethwait, John", "bounds_geometry": ["POLYGON((-63 -64,-57.8 -64,-52.6 -64,-47.4 -64,-42.2 -64,-37 -64,-31.799999999999997 -64,-26.6 -64,-21.4 -64,-16.199999999999996 -64,-11 -64,-11 -65.3,-11 -66.6,-11 -67.9,-11 -69.2,-11 -70.5,-11 -71.8,-11 -73.1,-11 -74.4,-11 -75.7,-11 -77,-16.2 -77,-21.4 -77,-26.6 -77,-31.8 -77,-37 -77,-42.2 -77,-47.4 -77,-52.6 -77,-57.800000000000004 -77,-63 -77,-63 -75.7,-63 -74.4,-63 -73.1,-63 -71.8,-63 -70.5,-63 -69.2,-63 -67.9,-63 -66.6,-63 -65.3,-63 -64))"], "date_created": "Tue, 11 Feb 2025 00:00:00 GMT", "description": "Morphological, fecundity, and age data of Trematomus scotti from Andvord Bay and the Weddell Sea.", "east": -11.0, "geometry": ["POINT(-37 -70.5)"], "keywords": "Age; Antarctica; Biota; Cryonotothenioid; Cryosphere; Fecundity; Growth; Length; Nototheniidae; Oceans; Otolith; Reproduction; Weight", "locations": "Antarctica; Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Desvignes, Thomas; Valdivieso, Alejandro; Sguotti, Camilla; Cal\u00ec, Federico; Riginella, Emilio; Streeter, Margaret; Grondin, Jacob; Le Francois, Nathalie; Lucassen, Magnus; Mark, Felix C; Detrich, H. William; Papetti, Chiara; Postlethwait, John; La Mesa, Mario", "project_titles": "EAGER: Origin and Physiological Consequences of a Neoplasm Outbreak in Antarctic Fish ", "projects": [{"proj_uid": "p0010221", "repository": "USAP-DC", "title": "EAGER: Origin and Physiological Consequences of a Neoplasm Outbreak in Antarctic Fish "}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "Morphological, fecundity, and age data of Trematomus scotti from Andvord Bay and the Weddell Sea.", "uid": "601893", "west": -63.0}, {"awards": "0228842 Grew, Edward", "bounds_geometry": ["POLYGON((76 -69.3,76.05 -69.3,76.1 -69.3,76.15 -69.3,76.2 -69.3,76.25 -69.3,76.3 -69.3,76.35 -69.3,76.4 -69.3,76.45 -69.3,76.5 -69.3,76.5 -69.32,76.5 -69.34,76.5 -69.36,76.5 -69.38,76.5 -69.4,76.5 -69.42,76.5 -69.44,76.5 -69.46,76.5 -69.48,76.5 -69.5,76.45 -69.5,76.4 -69.5,76.35 -69.5,76.3 -69.5,76.25 -69.5,76.2 -69.5,76.15 -69.5,76.1 -69.5,76.05 -69.5,76 -69.5,76 -69.48,76 -69.46,76 -69.44,76 -69.42,76 -69.4,76 -69.38,76 -69.36,76 -69.34,76 -69.32,76 -69.3))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts per million in rocks subjected to conditions of the middle and lower crust, that is, temperatures of 700 degrees C or more in the granulite-facies, which is characterized by very low water activities at pressures of 5 to 10 kbar (18-35 km burial). Devolatization reactions with loss of aqueous fluid and partial melting with removal of melt have been cited as primary causes for boron depletion under granulite-facies conditions. Despite the pervasiveness of both these processes, rocks rich in boron are locally found in the granulite-facies, that is, there are mechanisms for retaining boron during the metamorphic process. The Larsemann Hills, Prydz Bay, Antarctica, are a prime example. More than 20 lenses and layered bodies containing four borosilicate mineral species crop out over a 50 square kilometer area, which thus would be well suited for research on boron-rich granulite-facies metamorphic rocks. While most investigators have focused on the causes for loss of boron, this work will investigate how boron is retained during high-grade metamorphism. Field observations and mapping in the Larsemann Hills, chemical analyses of minerals and their host rocks, and microprobe age dating will be used to identify possible precursors and deduce how the precursor materials recrystallized into borosilicate rocks under granulite-facies conditions. \n\nThe working hypothesis is that high initial boron content facilitates retention of boron during metamorphism because above a certain threshold boron content, a mechanism \u0027kicks in\u0027 that facilitates retention of boron in metamorphosed rocks. For example, in a rock with large amounts of the borosilicate tourmaline, such as stratabound tourmalinite, the breakdown of tourmaline to melt could result in the formation of prismatine and grandidierite, two borosilicates found in the Larsemann Hills. This situation is rarely observed in rocks with modest boron content, in which breakdown of tourmaline releases boron into partial melts, which in turn remove boron when they leave the system. Stratabound tourmalinite is associated with manganese-rich quartzite, phosphorus-rich rocks and sulfide concentrations that could be diagnostic for recognizing a tourmalinite protolith in a highly metamorphosed complex where sedimentary features have been destroyed by deformation. Because partial melting plays an important role in the fate of boron during metamorphism, our field and laboratory research will focus on the relationship between the borosilicate units, granite pegmatites and other granitic intrusives. The results of our study will provide information on cycling of boron at deeper levels in the Earth\u0027s crust and on possible sources of boron for granites originating from deep-seated rocks. An undergraduate student will participate in the electron microprobe age-dating of monazite and xenotime as part of a senior project, thereby integrating the proposed research into the educational mission of the University of Maine. In response to a proposal for fieldwork, the Australian Antarctic Division, which maintains Davis station near the Larsemann Hills, has indicated that they will support the Antarctic fieldwork.", "east": 76.5, "geometry": ["POINT(76.25 -69.4)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Geochronology; Solid Earth", "locations": "Antarctica", "north": -69.3, "nsf_funding_programs": null, "persons": "Grew, Edward", "project_titles": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "projects": [{"proj_uid": "p0000431", "repository": "USAP-DC", "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.5, "title": "Boron in Antarctic granulite-facies rocks: under what conditions is boron retained in the middle crust?", "uid": "600030", "west": 76.0}, {"awards": "0125098 Emslie, Steven", "bounds_geometry": ["POLYGON((-50 -60,-29 -60,-8 -60,13 -60,34 -60,55 -60,76 -60,97 -60,118 -60,139 -60,160 -60,160 -63,160 -66,160 -69,160 -72,160 -75,160 -78,160 -81,160 -84,160 -87,160 -90,139 -90,118 -90,97 -90,76 -90,55 -90,34 -90,13 -90,-8 -90,-29 -90,-50 -90,-50 -87,-50 -84,-50 -81,-50 -78,-50 -75,-50 -72,-50 -69,-50 -66,-50 -63,-50 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project will build on previous studies to investigate the occupation history and diet of Adelie penguins (Pygoscelis adeliae) in the Ross Sea region, Antarctica, with excavations of abandoned and active penguin colonies. Numerous active and abandoned colonies exist on the Victoria Land coast, from Cape Adare to Marble Point will be sampled. Some of these sites have been radiocarbon-dated and indicate a long occupation history for Adelie penguins extending to 13,000 years before present (B. P.). The material recovered from excavations, as demonstrated from previous investigations, will include penguin bones, tissue, and eggshell fragments as well as abundant remains of prey (fish bones, otoliths, squid beaks) preserved in ornithogenic (formed from bird guano) soils. These organic remains will be quantified and subjected to radiocarbon analyses to obtain a colonization history of penguins in this region. Identification of prey remains in the sediments will allow assessment of penguin diet. \n\nOther data (ancient DNA) from these sites will be analyzed through collaboration with New Zealand scientists. Past climatic conditions will be interpreted from published ice-core and marine-sediment records. These data will be used to test the hypothesis that Adelie penguins respond to climate change, past and present, in a predictable manner. In addition, the hypothesis that Adelie penguins alter their diet in accordance with climate, sea-ice conditions, and other marine environmental variables along a latitudinal gradient will be tested. Graduate and undergraduate students will be involved in this project and a project Web site will be developed to report results and maintain educational interaction between the PI and students at local middle and high schools in Wilmington, NC.", "east": 160.0, "geometry": ["POINT(55 -75)"], "keywords": "Antarctica; Biota; Geochronology; Oceans; Paleoclimate; Penguin; Radiocarbon; Ross Sea; Southern Ocean", "locations": "Southern Ocean; Antarctica; Ross Sea", "north": -60.0, "nsf_funding_programs": null, "persons": "Emslie, Steven D.", "project_titles": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "projects": [{"proj_uid": "p0000220", "repository": "USAP-DC", "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Occupation History and Diet of Adelie Penguins in the Ross Sea Region", "uid": "600028", "west": -50.0}]

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