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，以记录以前的高架立场，并评估在Mercer Ice流（以前为Ice Stream A）附近的俄亥俄州范围内的西南极冰盖（WAIS）的稳定性。现场位置位于“瓶颈”中，这是一个独特的，相对狭窄的通道，在连接西方和南极冰盖的跨二山脉。该位置位于冰鸿沟附近，因此位于良好的位置以确定过去的内部冰升高。 该研究将涉及冰川沉积物和侵蚀特征的地质图，并在俄亥俄州范围内的宇宙源性表面暴露日期结合使用，以确定过去较高的冰盖水平和局部冰川波动的年代学。 新鲜冰川异常的暴露年龄，在当前冰层高达60 m的情况下将用于限制该部门中最后一个高架的时间和随后的降低。 冰片表面碎屑带的暴露年龄将限制目前高程附近的连续冰盖的持续时间。 还将从当地冰川冰ora的年表中获得免费的当地代理气候记录。 从拟议的研究中获得的数据将有助于开发wais的时间依赖性，非平衡模型，自20，000年前的最后一次冰川最多，这是西南极冰盖倡议的主要目标。 从这个关键位置的冰盖冰层高程的年龄控制在Mercer Ice流的头部附近，将完成从罗斯海的冰河时代末端，通过McMurdo Sound和Southern Transantantarctic Mountains延伸到附近的一开始区域冰划分。此外，瓶颈中的冰川地质记录将反映WAIS和EAIS相互作用的历史，这些历史可用于检验WAIS的更新世崩溃的假设。 由于其与海平面的联系，瓦斯的未来行为引起了社会的重大关注。 南极冰盖的融化将提高海平面，对居住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，以准确预测冰盖的未来行为。 此外，拟议的研究还纳入了研究生和本科生教育，并将他们参与具有社会意义的目标的研究