COLLABORATIVE RESEARCH: Determining Transient Physical Conditions Under the Southern Laurentide Ice Sheet Using Geologic Information and Numerical Modeling

作者：David M. Mickelson、Paul Cutler（美国威斯康星大学地质与地球物理系）、Douglas R. MacAyeal（美国芝加哥大学地球物理科学系）和Patrick M. Colgan（美国东北大学地质学系）本文将冰川地质记录与数值模拟相结合，重建美国威斯康辛州晚期南劳伦泰德冰盖（SLIS）的动力学和冰下环境。我们之所以关注SLIS，是因为从北到南的地貌组合有明显的对比，而且冰盖的记录在时间和空间上都有很好的记录。数据将在地理信息系统中进行组织和分析。我们的冰盖模型是二维的、随时间变化的，除了上覆的冰外，还包含了地下1公里以上的冰。通过添加“地质包”，该模型将适应处理基底/地下过程。这将包括永久冻土、水文、基底运动和土壤动力学的处理。这个模型将帮助我们了解大湖地区冰川景观形成的条件。

9814371MickelsonDetermining Transient Physical Conditions under the Southern Laurentide IceSheet Using Geologic Information and Numerical Modeling by David M. Mickelson and Paul Cutler (Department of Geology and Geophysics, University of Wisconsin, Douglas R. MacAyeal (Department of Geophysical Sciences, University of Chicago) and Patrick M. Colgan (Department of Geology, Northeastern University). We will reconstruct the dynamics and subglacial environment of the southern Laurentide Ice Sheet (SLIS) during the late Wisconsin by integrating the glacial geologic record with numerical ice-sheet modeling. We focus on the SLIS because there are striking contrasts in landform assemblages from north to south, and the record of ice sheets is well documented in time and space. Data will be organized and analyzed in a geographic information system. Our ice-sheet model is two-dimensional, time-dependent, and incorporates the upper 1-km of the subsurface in addition to overlying ice. The model willbe adapted to handle basal/subsurface processes by adding a 'geologic package'. This will include treatment of permafrost, hydrology, basal motion and till dynamics. This modeling will help us understand the conditions of formation of the glacial landscape of the Great Lakes area.