Multi-proxy record of Holocene glacial history of the Spearhead and Fitzsimmons ranges, southern Coast Mountains, British Columbia

摘要

Evidence from glacier forefields and lakes is used to reconstruct Holocene glacier fluctuations in the Spearhead and Fitzsimmons ranges in southwest British Columbia. Radiocarbon ages on detrital wood and trees killed by advancing ice and changes in sediment delivery to downstream proglacial lakes indicate that glaciers expanded from minimum extents in the early Holocene to their maximum extents about two to three centuries ago during the Little Ice Age. The data indicate that glaciers advanced 8630-8020, 6950-6750, 3580-2990, and probably 4530-4090 cal yr BP, and repeatedly during the past millennium. Little Ice Age moraines dated using dendrochronology and lichenometry date to early in the 18th century and in the 1830s and 1890s. Limitations inherent in lacustrine and terrestrial-based methods of documenting Holocene glacier fluctuations are minimized by using the two records together. (c) 2006 Published by Elsevier Ltd.