Holocene history of the Bugaboo glacier, British Columbia

Abstract

Sequences of tills, buried paleosols, wood, and tephra in moraines provide a fairly complete record of Holocene fluctuations of the Bugaboo glacier in British Columbia. The oldest till known to be exposed in the lateral moraines, apparently associated with an end moraine of the regionally known Crowfoot advance, is overlain by Mazama tephra, and is possibly early Holocene, but probably latest Pleistocene, in age. A paleosol incorporating the tephra and capping this till developed during early to middle Holocene time; it represents the warm and/or dry Altithermal interval. Subsequent (Neoglacial) advances deposited tills after 3.39 ka but before 3.07 ka, in the period ca. 2.5-1.9 ka, and in the period from ca. 0.9 ka to the nineteenth century. Recessional intervals are marked by paleosols and a former moraine gully, now filled. Results of the Bugaboo glacier study increase the resolution of known Neoglacial history in the Canadian Cordillera and generally demonstrate the usefulness of lateral-moraine stratigraphy.