Abstract
In recent years, the “subglacial deforming bed” has attracted attention as a factor of glacier dynamics. Subglacial deforming beds, named T8-till and T9-till respectively in this study, were formed at two locations in the Hidak Mountain Range during the glacier's maximum advance (Poroshiri Stade) of the Last Glacial Stage. These subglacial deforming beds are characterized by deformation structures such as shear planes, folds and fault gouge formed under compaction in the vertical direction and drag in the horizontal direction. T8-till and T9-till had been deformed by two cycles and one cycle of glacial advance and retreat, respectively. Strain at these subglacial deforming beds reconstructed using shear angle and degree of fracturing indicate that T8-till developed beneath the first warm-based and the second coldbased glaciers, while T9-till was beneath the cold-based glacier.
