Glacial Phenomena near Cranbrook, British Columbia

Abstract

Evidence is presented to show that, in the Cranbrook district, the Rocky Mountain trench and the lower reaches of its tributary valleys were not heavily eroded by the ice of the Wisconsin stage and that the ice sheet disappeared from the trench by stagnation and melting instead of by normal retreat. Both of these phenomena are commonly seen along the southern margin of the ice sheet in the United States but are in such marked contrast to what is observed over most of British Columbia, particularly near the coast, that they have so far escaped the attention they deserve in that province. The preservation of the rich Tertiary placers of the Cariboo and Cranbrook districts is due to limited erosion by the ice, so that the recognition of this condition elsewhere in the province may result in the discovery of other equally rich fields.