GEOG 216 Lecture Notes - Lecture 11: Cirque Glacier, Laurentide Ice Sheet, Glacier
18 May 2018
School
Department
Course
Professor
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Document Summary
Debris trapped in the basal ice acts like sandpaper as the glacier flows over the underlying bedrock. This results in the abrasion of both the bedrock and basal debris. The fine powdered rock produced by this rock is called rock flour. Cirque glacier: excavates some of the underlying geology where it"s forming. Alpine glacial systems: post-glacial water bodies (little lakes in cirques cirque lakes/tarn. The high pressure on the stross side of a rock obstacle causes pressure melting, but the lower pressure on the lee side results in freezing and plucking. Regelation happens when a glacier is trying to get through an obstacle. Glaciers exert tremendous force on the landscape and are capable of significant erosion and sediment transport. Glaciers operate like a conveyor belt in that they transport entrained sediment to the end of the glacier and then dump it. At the base of the glacier (subglacial - basal ice)
