CGRG Bibliography of Canadian Geomorphology
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Author : Dyke, A.S.,
Date : 2007.
Title : Deglaciation of Northern Baffin Island, with a focus on the Steensby Inlet Ice Stream,
Publication : CANQUA Ottawa 2007. Canadian Quaternary Association Conference, June 4-8, 2007. Carleton University, Ottawa, Ontario, Canada.
Issue :
Page(s) :
Abstract
The deglacial history of northern Baffin Island spans from the Last Glacial Maximum (LGM) to present day, Baffin Island being the only part of North America that preserves a “continuous” record of Holocene ice recession. At LGM the region is thought to have been covered by ice flowing from the Foxe Dome (over Foxe Basin) to Baffin Bay. A large ice stream flowed along Prince Regent Inlet and Lancaster Sound and smaller ice streams flowed along Admiralty Inlet and Milne/Navy Board Inlet. Ice recession is mapped at sub-centennial resolution and well dated for the interval 10-4 14C ka BP. Prominent end moraines formed at the end of Younger Dryas time, throughout the interval 8.5-7.5 ka BP, and at ca 5.4 ka BP. Removal of Laurentide ice from northern Foxe Basin during the interval 6.5-6 ka BP resulted in a regional rearrangement of ice-flow directions and establishment of the Steensby Inlet Ice Stream. From its maximum size (170 km wide x 160 km long) at 6 ka BP, the ice stream devolved into valley-controlled ice streams by 4.8 ka BP. The western side of the ice stream, which traversed Paleozoic carbonate rocks and Precambrian gneisses, lasted for ca 500 years. Carbonate debris entrainment and dispersion, as characterized by a dense network of till samples, indicate rapid erosion at the head of warm-based ice flow and plug-like dispersion across the gneisses. Rough, but conservative, volume calculations of carbonate-derived drift yield an average rate of erosion of carbonate rock of ca 0.5 cm per year while that part of the ice stream operated.
Bibliography of Canadian Geomorphology