CGRG Bibliography of Canadian Geomorphology
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Author : Gilbert, R., and Shaw, J.
Date : 1994
Title : Inferred subglacial meltwater origin of lakes on the southern border of the Canadian Shield
Publication : Canadian Journal of Earth Sciences.
Issue : 31:
Page(s) : 1630-1637
Abstract
The Paleozoic escarpment that borders the Frontenac Axis of the Canadin Shield in southeastern Ontario lies across the flow of Pleistocene glaciers and their subglacial meltwater, and is cut by a series of deep channels incised into the bedrock at the escarpment. A subbottom acoustic survey of two of these channels revealed the shape of the bedrock surface to show a smooth-walled dominant depression up to 100 m below the land surface and flanked by one or more secondary depressions. The pattern is similar to that of subglacial fluvial erosion marks more than three orders of magnitude smaller found in bedrock throughout the region. We ascribe the roigin of these channels to periodic, large flows of water beneath the Laurentide Ice Sheet. The escarpment formed a varrier through which the flow was forced while the ice was still largely in contact with the surrounding surface.
Bibliography of Canadian Geomorphology