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

9725360 Iverson该奖项支持一个项目，该项目使用环剪装置进行实验，该装置将大型水饱和till试样变形到高应变，用于till粉碎，流变学和织物发展的研究。尽管人们普遍认识到冰下沉积物影响冰盖的动力学，但控制沉积物质量平衡的因素仍然不清楚。在少数冰川下的直接测量似乎表明了各种各样的行为，从普遍的河床变形到集中在冰川底部的运动。对这些测量结果的解释和对基底沉积物运移的精确建模需要实验室研究，旨在揭示控制冰川床运动分布的基本因素。

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.