Holocene glacial history of the Bowser River Watershed, Northern Coast Mountains, British Columbia

Accelerated glacial recession and downwasting of glaciers in the Bowser River Watershed of the northern British Columbia Coast Mountains have exposed subfossil wood remains and laterally contiguous wood mat layers. To develop an understanding of Holocene glacial fluctuations in this region, field in...

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Bibliographic Details
Main Author: St-Hilaire, Vikki Maria
Other Authors: Smith, Daniel J.
Language:English
en
Published: 2014
Subjects:
Online Access:http://hdl.handle.net/1828/5817
Description
Summary:Accelerated glacial recession and downwasting of glaciers in the Bowser River Watershed of the northern British Columbia Coast Mountains have exposed subfossil wood remains and laterally contiguous wood mat layers. To develop an understanding of Holocene glacial fluctuations in this region, field investigations were conducted in 2005, 2006 and 2013 at Frank Mackie, Charlie, Salmon and Canoe glaciers. These wood remains represent periods of Holocene glacier advance, when glaciers expanded and overwhelmed downvalley forests. Dendroglaciology and radiocarbon analyses revealed five intervals of glacial expansion: (1) a mid-Holocene advance at 5.7-5.1 ka cal. yr BP; (2) an early Tiedemann advance at 3.6-3.4 ka cal. yr BP; (3) a late Tiedemann advance at 2.7-2.4 ka cal. yr BP; (4) a First Millennium AD Advance at 1.8-1.6 ka cal. yr BP; and, (5) three advances during the Little Ice Age at 0.9-0.7, 0.5 and 0.2-0.1 ka cal. yr BP. These results provide new evidence for mid-Holocene glacier activity in northern British Columbia, as well as supporting previous research that Holocene glacier advances were episodic and regionally synchronous. === Graduate === 0368