CGRG Bibliography of Canadian Geomorphology
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Author : Beget, J.E.; Pedersen, T.F.; and Muhs, D.
Date : 2004.
Title : Terrestrial-marine correlation of the 24 kyr BP Dawson Tephra: Implications for dispersal and preservation of Alaskan tephra deposits.
Publication : American Geophysical Union Fall Meeting. December 13-17, 2004. San Francisco, California.
Issue :
Page(s) :
Abstract
The Dawson tephra, radiocarbon-dated to ca. 24,000 yr BP, is as much as 50 cm thick in Pleistocene sediments in Yukon Territory of Canada, but is not found in nearby parts of Alaska. Nonetheless, the geochemical characteristics of the tephra suggested derivation from an Aleutian arc volcano (Westgate et al., 2000). Its source was unknown until proximal deposits were recognized at Emmons Lake Volcanic Center (ELVC) on the Alaska Peninsula (Mangan et al., 2003). We have identified Dawson tephra in ODP core 880B, collected in the Northeast Pacific Ocean. The Dawson tephra also occurs in discontinuous small pods in two new localities near Fairbanks in central Alaska. Our data suggest the Dawson tephra was dispersed from the ELVC principally to the southeast over the North Pacific , and then carried to the northeast by high altitude winds. Reconstructions of the volume and distribution of individual tephras or of arc-wide explosive volcanism in Alaska must incorporate data from proximal and distal terrestrial localities, as well as marine cores.
Bibliography of Canadian Geomorphology