Using Central Arctic Ocean and Norwegian-Greenland Sea Sediments as Recorders of High Canadian Arctic Climate During the Pleistocene

全球气候变化以不成比例的大方式影响极地地区，特别是北极地区，造成陆地和海洋冰盖、海冰和海洋温度的巨大变化。例如，这些变化不仅发生在地质时间尺度上，而且被认为是在更短的时间尺度上发生的，以应对大气中二氧化碳含量的变化。了解主要冰盖对已发生的气候变化的响应是海洋生态环境研究的主要目标之一。这种理解是建立在对该区域沉积历史的详细研究基础上的，其中包括古代和现代沉积路径的位置、对高质量沉积岩心的密集样品的检查以及环境事件的区域对比。该项目将应用这些技术来研究北半球更新世冰盖衰退的程度和时间。在这个时候，加拿大北极高地的冰川消融是一个很大的推测。已经提出的假设范围从无冰地区到被东与格陵兰冰盖合并的因努蒂安冰盖和南边的劳伦蒂德冰盖。解决这个问题的关键在于确定一种示踪剂，它可能明确地与实际冰盖的进退有关。该项目将结合富含高岭石的地层(指示伊丽莎白女王群岛的源区)，研究在选定的沉积物样品中出现的高粗组分丰度(表明普遍的冰川消退)。一份详细的碳14分析计划将提供一个精确的时间刻度。

Global climatic changes affect polar regions, specifically the arctic,in disproportionately large ways, producing substantial variations inthe extent of terrestrial and marine ice sheets, of sea ice, and ofocean temperatures. These variations have not only occurred overgeologic time scales, but are thought to occur over much shorter timescales in response to the varying carbon dioxide content of theatmosphere, as an example. Understanding the responses of major ice sheets to the climaticchanges that have occurred is one of the primary objectives of marinepaleoenvironmental research. Such understanding is based on thedetailed study of the sedimentation history of the region, whichincludes the location of ancient and modern sediment pathways, theexamination of closely spaced samples from high quality sedimentcores, and the regional correlation of environmental events. This project will apply these techniques in a study of the extent andtiming of the decay of the northern hemisphere pleistocene ice sheet. The deglaciation of the high Canadian Arctic is quite speculative atthis time. Hypotheses that have been advanced range from the areabeing ice-free to being covered by the Innuitian Ice Sheet which hadmerged with the Greenland Ice Sheet to the east, and the LaurentideIce Sheet to the south. The key to resolving this question lies inidentifying a tracer that may be unambiguously related to advances andretreats of an actual ice sheet. This project will examine theoccurrences of high coarse-fraction abundance in selected sedimentsamples (indicative of general deglaciation) in conjunction withkaolinite-rich layers (indicative of a Queen Elizabeth Islands sourceregion). A detailed Carbon-14 analysis program will provide a precisetime scale.