Rheology of Basal Ice

该奖项支持一项为期两年的基冰流变学研究。这项研究包括两个主要部分：1)测量北诺威冰川Engabreen底部人工不规则区周围的冰流场；2)发展一个描述基冰中三维流场的理论(数值)模型。通过Engabreen下基岩的隧道将为直接测量基冰中的流场提供独特的环境和机会。速度场将通过使用摄像机监控冰块中标志物的位置来确定。数值模型将基于明尼苏达大学现有的有限元代码，利用明尼苏达超级计算机研究所的设施。将模型与实验观察到的流场进行比较，可以对各种本构关系进行评估。将确定与观察到的流场最佳匹配的模型中的材料常数的数值。

This award supports a two year study of the rheology of basal ice. The study has two principal parts: 1) measurements of the ice flow field around an artificial irregularity at the base of the glacier Engabreen in northern Norwway; and 2) development of a theoretical (numerical) model, that describes the threedimensional flow field in basal ice. Tunnels through the bedrock beneath Engabreen, will provide the unique setting and opportunity to directly measure the flow field in basal ice. The velocity field will be determined by using a video camera to monitor the position of markers in the ice. The numerical model will be based on an existing finite element code at the University of Minnesota, taking advantage of the facilities at the Minnesota Supercomputer Institute. Comparison between the model and the experimentally observed flow fields will permit an evaluation of various constitutive laws. Numerical values will be determined for the material constants in the models that give the best fit to the observed flow field.