Distribution of Motion Beneath Soft-Bedded Glaciers: Laboratory Studies of Till Deformation and Non-Hydrostatic Pore Pressure

点击翻译按钮获取中文摘要

9725360 Iverson This award supports a program to conduct experiments with a ring-shear device that deforms a large water-saturated till specimen to high strains, for studies of till comminution, rheology, and fabric development. Despite the widespread realization that subglacial sediment affects the dynamics of ice sheets, the factors that control the sediment mass balance remain obscure. Direct measurements beneath a handful of glaciers seem to indicate a wide range of behavior, varying from pervasive deformation of the bed to motion that is focused at the glacier sole. The interpretation of these measurements and the accurate modeling of basal sediment transport requires laboratory studies aimed at revealing the fundamental factors that control the distribution of motion at the glacier bed.