CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Friele, P.A.; and Clague, J.J.
Date : 2002.
Title : Readvance of glaciers in the British Columbia Coast Mountains at the end of the last glaciation.
Publication : Quaternary International
Issue : 87(1):
Page(s) : 45-58.
Abstract
Late Quaternary sediments and landforms at the head of Howe Sound, a fjord in the British Columbia Coast Mountains, provide a detailed record of final decay of the southwestern sector of the Cordilleran ice sheet at the end of the Pleistocene. The upper reaches of Mamquam River valley, a mountain valley at the head of the fjord east of the town of Squamish, were ice free and locally treed as early as 14000 years ago (11900 14Cyr BP). Folding and faulting of late-glacial lacustrine sediments in Mamquam valley may record a glacier readvance, correlative with the Sumas event in the Fraser Lowland to the southeast. By 12900 years ago (10690 14Cyr BP), the trunk glacier in Howe Sound had retreated from a Sumas-age moraine at Porteau Cove, 15km south of Squamish. By 12800 years ago (10650 14Cyr BP), the glacier terminus stood near the present fjord head with the sea at an elevation of about 40-50m a.s.l. Shortly after 12800 years ago, during the Younger Dryas chronozone, the trunk glacier in Squamish valley readvanced a short distance and then retreated for a final time. Tributary valleys were probably completely deglaciated by 11300 years ago (9920 14Cyr BP), and certainly by 10600 years ago (9360 14Cyr BP). Relative sea level fell as deglaciation progressed; however, it did not fall below its present datum in the Squamish area until after 11200 years ago, at least 1300 years later than in the Fraser Lowland.
Bibliography of Canadian Geomorphology