Quaternary Glacial, Glacimarine and Glacilacustrine History

Abstract

Eastern Canada was almost completely glaciated from four major and several lesser ice centres on multiple occasions during the Quaternary. Most of the geomorphology relates to Marine Isotope Stage 2. Areas of resistant bedrock are dominated by glacial erosional features, such as roches mountonées. Glacial depositional landforms are prominent in southern Ontario, Québec, and the Maritime provinces. In Arctic Canada, glaciation had lesser effects on geomorphology, with the exception of the mountainous areas of Baffin and Ellesmere islands. Glacial retreat exposed the isostatically depressed coastlines to marine incursions. Champlain Sea glacimarine sediments cover the St. Lawrence and Ottawa Valleys. In the Great Lakes Lowlands and southern Canadian Shield, blockage of northward and eastward drainage led to the formation of successions of proglacial lakes and other paraglacial landforms during the transition from MIS 2 to the Holocene.