Collaborative Research: West Antarctic Ice Sheet Stability: The Glacial Geologic Record from the Ohio Range of the Horlick Mountains in the Bottleneck

合作研究：南极西部冰盖稳定性：瓶颈霍里克山脉俄亥俄山脉的冰川地质记录

• 批准号: 0338189
• 负责人: Harold Borns
• 金额: $ 13.01万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0338189&HistoricalAwards=false
• 关键词: Collaborative; Research; West; Antarctic; Ice

This award supports a project to document former high stands and assess the stability of the West Antarctic ice sheet (WAIS) at the Ohio Range near the head of Mercer Ice Stream (formerly Ice Stream A). The field location is situated in the "Bottleneck", a unique, relatively narrow passage in the Transantarctic Mountains connecting the West and East Antarctic ice sheets. The location lies near the ice divide and is thus well situated to determine past interior ice elevation. The research will involve geologic mapping of glacial deposits and erosion features combined with cosmogenic surface exposure dating on the Ohio Range nunataks to determine the chronology of past higher ice sheet levels and local glacier fluctuations. Exposure ages of fresh glacial erratics, up to 60 m above the present ice level will be used to constrain the timing of the last high stand and subsequent draw down of the WAIS in this sector. Exposure ages of debris bands on the ice sheet surface will constrain the duration of continuous ice cover near the present elevation. A complimentary local proxy climate record will also be obtained from a chronology of the local glacier moraines. Data obtained from the proposed research will contribute to the development of time-dependent, non-equilibrium models of the WAIS, at and since the last glacial maximum 20,000 years ago, a major objective of the West Antarctic Ice Sheet Initiative. Age control on ice sheet elevation from this key location, near the head of the Mercer Ice Stream, will complete chronologic coverage extending from the ice age terminus in the Ross Sea, through McMurdo Sound and the southern Transantarctic Mountains, to the onset area near the ice divide. In addition, the glacial geologic record in the Bottleneck will reflect the history of the interaction of WAIS and EAIS, which could be used to test hypotheses of Pleistocene collapse of the WAIS. The future behavior of the WAIS is of significant interest to society because of its linkage to sea level. Melting of Antarctic ice sheets would raise sea levels, negatively impacting the large portion of the human population living near the world's coasts. The research is designed to provide necessary data on the past history of the WAIS to the ice sheet modeling community in order to accurately predict the future behavior of the ice sheet. In addition, the proposed research incorporates both graduate and undergraduate student education and involves them in research with goals that are of societal significance

该奖项支持一个项目，以记录以前的高立场和评估西南极冰盖（WAIS）的稳定性在俄亥俄州范围附近的头部美世冰流（以前的冰流A）。该油田位于“瓶颈”，这是连接南极西部和东部冰盖的横贯南极山脉中一条独特的相对狭窄的通道。该位置位于冰分水岭附近，因此非常适合确定过去的内部冰高程。 这项研究将涉及冰川沉积物和侵蚀特征的地质测绘，以及俄亥俄州山脉冰原岛峰的宇宙成因表面暴露年代测定，以确定过去较高冰盖水平和当地冰川波动的年代。 暴露年龄的新鲜冰川erratics，高达60米以上的目前冰的水平将被用来限制的时间，最后一个高的立场和随后的提请下降的WAIS在这一部门。 冰盖表面碎屑带的暴露年龄将限制当前海拔附近连续冰盖的持续时间。 还将从当地冰川冰碛的年表中获得一份免费的当地代用气候记录。 从拟议的研究中获得的数据将有助于在20 000年前的最后一次冰川高峰期和自那以来建立与时间有关的WAIS非平衡模型，这是西南极冰盖倡议的一个主要目标。 年龄控制冰盖海拔从这个关键位置，靠近头部的美世冰流，将完成年表的覆盖范围从冰河时代的终点在罗斯海，通过麦克默多声音和南部的跨南极山脉，附近的冰分水岭的发病地区。此外，瓶颈地区的冰川地质记录将反映WAIS和EAIS相互作用的历史，这可以用来检验WAIS更新世崩塌的假设。 由于WAIS与海平面的联系，其未来的行为对社会具有重大意义。 南极冰盖的融化将使海平面上升，对生活在世界海岸附近的大部分人口产生负面影响。 该研究旨在为冰盖建模社区提供有关WAIS过去历史的必要数据，以便准确预测冰盖的未来行为。 此外，拟议的研究将研究生和本科生教育结合起来，让他们参与具有社会意义的研究目标