Chronology of the West Antarctic Ice Sheet: New Evidence from Marie Byrd Land Nunataks

西南极冰盖年代学：来自玛丽伯德地努纳塔克群岛的新证据

• 批准号: 0087709
• 负责人: Mark Kurz
• 金额: $ 17.63万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-15 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0087709&HistoricalAwards=false
• 关键词: Chronology; West; Antarctic; Ice; Sheet

0087709Kurz This award supports a project for a detailed laboratory-based study of glacial moraine boulders collected on the flank of Mt. Waesche, a nunatak in the Executive Committee Range, Marie Byrd Land, West Antarctica. Preliminary work on these samples resulted in measurement of past ice sheet elevations in interior West Antarctica. Funds are requested here to measure exposure ages in the remaining samples from the moraine and adjacent volcanic bedrock. The goal is to use a combination of field observations, surface exposure dating (Helium-3, Neon-21 and Chlorine-36) and Argon-40/Argon-39 dating to constrain past elevations of the West Antarctic ice sheet (WAIS). The initial study demonstrated that higher past ice levels are recorded by moraines, composed of volcanic debris left behind by receding ice, and that Helium-3 and Chlorine-36 surface exposure dating can be used to constrain the timing of past ice high stands. It is expected that these analyses will refine the initial results pertaining to the last deglaciation and provide a unique record of earlier ice sheet elevations. The primary long-term objective is to provide chronological and elevation data of the paleoglaciology of the interior of the WAIS prior to 10 kA. The unique record of surface ice elevations at Mt. Waesche provides key constraints on the behavior of the ice sheet and its response to climate and sea level change. This information will contribute strongly to determining why the WAIS behaved as it did during the last deglaciation and the previous interglacial, and will help efforts to predict how it will change in the future.

0087709Kurz 该奖项支持对在韦什山（Mt. Waesche）侧翼收集的冰川冰碛巨石进行详细的实验室研究的项目，韦什山是南极洲西部玛丽伯德地执行委员会山脉的努纳塔克峰。 对这些样本的初步工作测量了南极洲西部内陆过去冰盖的海拔。 这里需要资金来测量来自冰碛和邻近火山基岩的剩余样本的暴露年龄。 目标是结合实地观测、表面暴露测年（氦 3、氖 21 和氯 36）和氩 40/氩 39 测年来限制西南极冰盖 (WAIS) 过去的海拔。 初步研究表明，过去较高的冰位是由冰碛记录的，冰碛由冰消退留下的火山碎片组成，氦 3 和氯 36 表面暴露测年可用于限制过去冰位高位的时间。 预计这些分析将完善有关上次冰消期的初步结果，并提供早期冰盖海拔的独特记录。 主要的长期目标是提供 10 kA 之前 WAIS 内部古冰川的年代和高程数据。 瓦埃什山表面冰海拔的独特记录为冰盖的行为及其对气候和海平面变化的响应提供了关键限制。 这些信息将有力地帮助确定 WAIS 在上一次冰消期和上一次间冰期期间的表现，并将有助于预测它未来将如何变化。