CGRG Bibliography of Canadian Geomorphology
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Author : Barnes, S.D.
Date : 1998
Title : Paleogeography and paleolimnology of latest Pleistocene Glacial Lake Champagne, Southern Yukon Territory, Canada
Publication : 1998 Annual Meeting, Geological Society of America, Toronto, October 26-29. Abstracts with Program.
Issue :
Page(s) :
Abstract
Detailed sedimentological analysis of sediment outcrops in south-central Yukon suggest that Glacial Lake Champagne (GLC) existed for a period of approximately 400 years, between ca. 12 500 and 10 500 BP in the valleys of the Yukon, and Dezadeash rivers and their tributaries. Initial stratigraphic evidence suggests that much of the shoreline of GLC was bounded by Cordilleran glacial ice, leading to variation in both sedimentary regime and lake surface elevation. On the basis of sedimentary structures, it is inferred that sediment deposition in GLC alternated between turbidity current-dominated underflow regimes and laminated silts and clays originating from over and interflows of sediment-laden glacial meltwater. Underflow sedimentation is evidenced by sandy facies containing climbing ripples and other cross-stratified forms, while inter and overflow regimes are represented by laminated (varved?) muds. GLC is suggested to have had at least two stands, with elevations indicated by several Gilbert-style deltas, one of which shows evidence of two distinct stages of GLC, first at 765m asl, followed by incision and continued deposition at 725 m asl. Sedimentology of these deltas is consistent with high-energy glacio-fluvial processes, and may in turn be used to infer paleogeographic conditions leading to the observed patterns of lake sedimentation.
Bibliography of Canadian Geomorphology