Expansion & Collapse of the Cordilleran Ice Sheet during the Quaternary

扩张

• 批准号: 0425382
• 负责人: Ingrid Hendy
• 金额: $ 27.55万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 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: 2004-08-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0425382&HistoricalAwards=false
• 关键词: Expansion; & Collapse; Cordilleran; Ice

Under this award the PIs will reconstruct the glacial history of the southern limb of the Cordilleran Ice sheet using glacial-marine sediments off the coast of Vancouver Island, British Columbia. Glacial advances and retreats associated with corresponding paleoclimatic events are poorly documented in the Pacific Northwest prior to 15 Ka. The jumbo piston core MD02-2496 will be used to interpret the history of growth and decay of the Cordilleran Ice Sheet over the last 500 Ka (at ODP Site 888). As the North Pacific greatly affects the climate (including the jet stream) downwind across North America, data obtained from this study should advance ability to model climate, to interpret glacial geomorphology and calculate continental denudation rates. Knowledge of when the British Columbian shelf was ice covered and when iceberg discharge occurred will test the feasibility of the migration route of early humans attempting to occupy the American continent via the North Pacific coastal route. The PI will examine particle size and sediment fabric within a jumbo piston core (MD02-2496) and at ODP Site 888 to determine ice sheet growth and decay in the region. At the same time high quality 14C dates and local sea surface temperatures will be generated based on planktonic foraminiferal d18O. Benthic d18O values will be employed to resolve changes in global ice volume.

根据该奖项，PI将利用不列颠哥伦比亚省温哥华岛海岸外的冰川海洋沉积物重建科迪勒拉冰盖南翼的冰川历史。 在太平洋西北部，15 Ka之前，与相应的古气候事件相关的冰川进退记录很少。MD 02 -2496大型活塞岩芯将用于解释过去500 Ka（ODP 888站）的科迪勒拉冰盖生长和衰退历史。由于北太平洋极大地影响了整个北美顺风的气候（包括急流），从这项研究中获得的数据应该提高模拟气候，解释冰川地貌和计算大陆剥蚀率的能力。了解不列颠哥伦比亚大陆架何时被冰覆盖以及何时发生冰山泄流，将测试早期人类试图通过北太平洋沿海路线占领美洲大陆的迁移路线的可行性。PI将检查大型活塞岩芯（MD 02 -2496）和ODP 888站点内的颗粒大小和沉积物结构，以确定该区域冰盖的生长和衰减。同时，高质量的14 C日期和当地的海面温度将产生基于浮游有孔虫d18 O。 海底d18 O值将用于解决全球冰量的变化。