CGRG Bibliography of Canadian Geomorphology
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Author : Bednarski, J.
Date : 2007.
Title : Surficial geology, Etset Lake, British Columbia; (NTS 94 P/11).
Publication : Geological Survey of Canada, Open File
Issue : 5506.
Page(s) :
Abstract
Etset Lake (NTS 94P/11) map area was glaciated by the Laurentide Ice Sheet during the Late Wisconsinan (ca. 25 000-10 000 years ago), which deposited clayey till over most of the area. Glacial flutings in the east central part of the map area record the ice flow from the north-northeast. Much of the area is now flat and boggy, with peat accumulations of 2 to 3 m that form hummocky terrain underlain by discontinuous permafrost. Till underlies the surface of broad forested uplands. The uplands are usually only a few metres above the surrounding wetlands. Deglaciation was recorded by numerous small moraines and crevasse-fill ridges that mark the pattern of glacial retreat as the ice sheet thinned and the margin became lobed. A tongue of ice persisted in the broad lowland incised by the modern Petitot River. Meltwater issuing from the retreating ice margin cut several large channels trending northwest across the map area. The largest of these, now occupied by Sahdoanah Creek, was the main drainage when Petitot River to the north was still covered by ice. These former meltwater channels can have significant, but localized, accumulations of glaciofluvial gravels.
Bibliography of Canadian Geomorphology