Neoglaciation in the southern Coast Mountains of British Columbia: chronology prior to the late Neoglacial maximum

Abstract

Moraine stratigraphy and morphology, radiocarbon dates from Klinaklini, Franklin, Tiedemann, Gilbert, and Bridge glaciers, and related information from elsewhere in the Coast Mountains are used to construct a chronology for glacier fluctuations. The Garibaldi phase of glacier expansion, 6000–5000 14C years BP, at the end of the early Holocene xerothermic interval, is indicated by overridden tree stumps. The mid-Neoglacial Tiedemann advance, 3300–1900 14C years BP, is represented by moraines, till, and meltwater sediments at three glaciers, but only Tiedemann Glacier attained its greatest Holocene extent at this time. Late Neoglacial expansion commenced before 900 14C years BP and continued without notable interruption until glaciers achieved their maximum post-Pleistocene expansion during the eighteenth and nineteenth centuries. Evidence for the Garibaldi and Tiedemann events is scarce within the Coast Mountains because of the more extensive late Neoglacial advance. However, correlative advances have been recognized in adjacent mountains within British Columbia, Washington, and Alaska.