Neoglacial history of the Coast Mountains near Bella Coola, British Columbia

Abstract

The maximum Holocene extent of glaciers in the study area is marked by late Neoglacial (Little Ice Age) terminal moraines. Moraine stratigraphy and 14C dates from a small number of sites suggest that glacier advance, almost as extensive as that of the late Neoglacial, occurred about 2500 14C years BP, and that late Neoglacial advance began well before 770 14C years BP (or the thirteenth century A.D.); glacier termini then stood close to the position of the climax moraines for several centuries. Dates of stabilization of end moraines at 16 glaciers were determined by dendrochronology, with tree-ring counts corrected for sampling errors and ecesis. Most terminal moraines date from 1860 to 1900. Many recessional moraines were formed between 1900 and 1940, coincident with a regionally documented phase of cooler and wetter climate. The proposed chronology is similar to results from elsewhere in the Canadian Cordillera.