COLLABORATIVE RESEARCH: Thickness, Extent and Basal Conditions the Scandinavian Ice Sheet Around the Last Glacial Maximum

合作项目：末次冰盛期附近斯堪的纳维亚冰盖的厚度、范围和基本条件。0087369）由大卫M. Mickelson和Paul Cutler（威斯康星大学麦迪逊分校地质与地球物理系）我们将重建斯堪的纳维亚冰盖（SIS）的厚度，范围和冰下环境，从~32 ka到~10 ka。 研究中将考虑四个仍有争议的方面：第一，末次盛冰期（LGM）冰盖的厚度是多少，挪威西部是否存在无冰区？ 第二，从物理上来说，将冰盖中部的地貌证据解释为大部分冰期都是以寒冷为基础的冰盖，这是否合理？ 第三，21 ka时俄罗斯冰盖东缘的范围是什么--这个时间没有地貌证据，但在GCM模拟过去气候的关键时间。 第四，气候和内部循环对调节冰动态的相对贡献是什么，SIS在全球范围内的作用是什么？为了回答这些问题，我们将把我们的努力集中在SIS的两个关键地区（挪威西部，以及从挪威北方向东进入俄罗斯的一条横断面），我们将在那里收集样品进行预固结测试和宇宙成因测年。 现场工作的结果以及其他可用的地质和气候数据将被纳入一个二维的，随时间变化的流带冰盖模型。

ABSTRACTA collaborative project: Thickness, Extent, and Basal Conditions of the Scandinavian Ice SheetAround the Last Glacial Maximum(Proposal Nr. 0087369)by David M. Mickelson and Paul Cutler (Department of Geology and Geophysics, University of Wisconsin-Madison)We will reconstruct the thickness, extent, and subglacial environment of the Scandinavian Ice Sheet (SIS) from ~32 ka to ~10 ka. Four still controversial aspects will be considered in the study: First, what was the thickness of the ice sheet at the last glacial maximum (LGM), and did ice-free regions exist in western Norway? Second, is it physically reasonable to interpret geomorphic evidence from the central parts of the ice sheet as indicating a cold-based ice sheet through most of glacial time? Third, what was the extent of the eastern margin of the ice sheet in Russia at 21 ka - a time for which no geomorphic evidence exists, but a key time in GCM simulations of past climates. Fourth, what were the relative contributions of climate and internal cycles to regulating ice dynamics, and what was the role of the SIS in a global context?To answer these questions, we will focus our efforts on two key regions of the SIS (western Norway, and a transect from northern Norway eastwards into Russia) where we will collect samples for preconsolidation tests and cosmogenic dating. The results from field work as well as other available geologic and climate data will be incorporated into a two-dimensional, time-dependent flowband ice-sheet model.