T3 Cordilleran Ice Sheet through the Quaternary: Chronology, Paleoenvironments, and Implications

Sunday, 22 September 2019
8:00 AM - 12:00 PM
Room 221AB, North Building

LIFE AT THE EDGE OF THE ICE: MULTI-PROXY PALAEOECOLOGICAL EVIDENCE FOR LATE PLEISTOCENE GLACIATION ON NORTHERN VANCOUVER ISLAND AND IMPLICATIONS FOR THE FIRST PEOPLING OF THE AMERICAS ALONG THE PACIFIC COAST

Paper number: T3-12
Program: Technical Sessions
Time: 11:00 AM – 11:15 AM

Authors

Abstract

Recent research has revealed human settlement on the Pacific coast of Canada at least as early as 14,000 years ago. However, consensus on the timing and pathway of the peopling of the Americas has been constrained by limitations on researchers’ understanding of the expansion and retreat of the Cordilleran ice mass during the Last Glacial Maximum (LGM). Much of the late Pleistocene record remains obscure due to shifting sea levels, poor understanding of regional Cordilleran ice extents, and a limited record of biota on the coast during this time. Using multi-proxy analysis of lake sediments from two sites on northern Vancouver Island, British Columbia, Canada, we reconstruct late glacial and early postglacial palaeoenvironments in the region extending back at least 17,600 years. Pollen, plant macrofossil, diatom, and ancient environmental DNA analyses demonstrate palaeogeographic change and ecological succession through the late Pleistocene. The early record from these sites indicates that the outer coast of northern Vancouver Island remained unglaciated by Cordilleran ice through most of the LGM and supported tundra-like vegetation potentially comparable to Beringia and elsewhere along the Pacific Rim. We relate these ancient environments to other archaeological, palaeontological, and ethnobotanical records, gaining new insight into the relationships of early peoples with the dynamic landscapes and seascapes of the region. These data demonstrate the presence of persistent late glacial refugia and habitable landscapes in coastal British Columbia, strengthening the hypothesis for the peopling of the Americas via a coastal route and significantly extending the depth of time over which the first migrations may have occurred.

Geological Society of America Abstracts with Programs. Vol. 51, No. 5

doi: 10.1130/abs/2019AM-335322

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