CGRG Bibliography of Canadian Geomorphology
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Author : French, H.; Demitroff, M.; Newell, W.; and DeJong, B.
Date : 2009.
Title : Past permafrost on the Mid-Atlantic Coast Plain; implications for relict permafrost in central Alaska and north-western Arctic Canada.
Publication : 2009 Annual Meeting of the American Association of Geographers. March 22-27, 2009. Rivera Hotel, Las Vegas, Nevada.
Issue :
Page(s) :
Abstract
Recent field investigations on the Mid-Atlantic Coastal Plain south of the glacial limits have identified non-diastrophic, post-depositional sedimentary structures that suggest Late-Pleistocene permafrost conditions extended as far south as southern Delaware, the Eastern Shore, and Southern Maryland. The area includes the vicinity of Washington DC. Optically-stimulated-luminescence dates, based upon stratigraphic studies in the Pine Barrens of southern New Jersey, permit construction of a tentative Late-Pleistocene permafrost chronology for the Atlantic Coastal Plain. This indicates Illinoian and Early-Wisconsinan episodes of permafrost, a Middle-Wisconsinan thermokarst event, and a Late-Wisconsinan period of either permafrost or deep seasonal frost that extended into the Early Holocene. The permafrost that no longer exists on the Mid-Atlantic Coastal Plain is termed past permafrost. This contrasts with the relict permafrost that currently exists in parts of central Alaska and north-western Arctic Canada. In central Alaska, relict permafrost is syngenetic, ice-rich, and Late-Pleistocene in age; in Mackenzie Delta region, icy permafrost is Late-Pleistocene and of either segregation-injection ice or buried glacier-ice origin; in interior Yukon, relict permafrost is ancient, over 750,000 years old. This paper compares the past permafrost that formed in the unglaciated lowlands of eastern North America with the relict permafrost that currently exists in parts of north-western Arctic North America.
Bibliography of Canadian Geomorphology