Laurentide, Cordilleran, and Montane glaciation in the western Peace River Grande Prairie Region, Alberta and British Columbia, Canada

Geological investigations over the last decade in the western Peace River-Grande Prairie district of northwestern Alberta and northeastern British Columbia have provided important chronostratigraphic information regarding Laurentide, Cordilleran and Montane Quaternary glacial events. Numerous C-14 age determinations, as well as stratigraphic and sedimentological analyses of numerous exposures, indicate that this area was first glaciated by Cordilleran ice sometime before the Late Wisconsinan. During the Late Wisconsinan, ca. 22,000-14,000 BP, Laurentide glacier ice covered much of the area. Between approximately 15,000 and 10,000 BP, Montane ice affected only the western part of the Peace region. There is no evidence for synchroneity of the ice advances and, therefore, no evidence for ice coalescence in this region. The resultant 'ice-free-corridor' was most likely a laterally fluctuating zone which existed during a several thousand year period in the Late Pleistocene. Climatic conditions along the 'corridor' during this period were probably unfavorable for human migration, but adequate for some plants and small animals. Numerous isolated areas along the western foothills of the northern Rocky Mountains, west of the Laurentide glaciation limit, were never glaciated during the Late Wisconsinan. Copyright (C) 1996 INQUA/Elsevier Science Ltd