CGRG Bibliography of Canadian Geomorphology
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Author : Blasco, S.M.; and McCarthy, F.M.G.
Date : 2004
Title : Late Quaternary history of the Georgian Bay Lake Basin- as viewed from the lakebed.
Publication : 49th Annual Meeting of the Geological Association and the Mineralogical Association of Canada. May 12-14, 2004. Brock University, St. Catharines, Ontario.
Issue :
Page(s) :
Abstract
Lake basin sediment and surficial bedrock stratigraphy of Georgian Bay are contributing new insights into the late Quaternary history of the Great Lakes region. Meltwater outbursts associated with the onset of late Wisconsinan deglaciation stripped the Georgian Bay basin of basal drift and generated S-form features and outwash channels in bedrock on the crest of the submerged Niagara Escarpment. Early to mid Holocene neotectonic activity in the basin is documented by pop-up ridges in bedrock outcrops and linear arrays of coalescing gas vents within glaciolacustrine and postglacial sediments. Evidence for post-Algonquin lake levels below outlet elevations includes eroded glaciolacustrine sediments, deep-water beaches, submerged waterfalls, relict drainage channels and in-situ tree stumps. Biostratigraphic evidence from a sediment core from the deepest sub-basin in Georgian Bay records low lake level conditions and evaporative conditions: total dissolved solids were higher than present and a more arid climate existed at 7.5ka. The above evidence suggests that lowstand Lake Hough levels were 30 to 50 m lower than previously thought between 9.5 and 7.5 ka allowing closed basin conditions to exist in Georgian Bay at intervals during this time period.
Bibliography of Canadian Geomorphology