CGRG Bibliography of Canadian Geomorphology
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Author : Brookes, I.A.; and Grant, D.R.
Date : 2003.
Title : Geological evidence for a palynologically defined cooling at 10-8 KABP in Southeastern Canada.
Publication : Joint Annual Meeting of the Canadian Quaternary Association and the Canadian Geomorphology Research Group. Halifax, Nova Scotia, June 8-12, 2003.
Issue :
Page(s) :
Abstract
Post-glacial pollen spectra over a wide area of southeastern Canada have been interpreted as showing that the general 'warmth-adapted' trend of regional vegetation change was interrupted between 10 and 8 14C kabp, reverting to conditions associated with a markedly cooler climate. This biotic reversal has been attributed to a climatic deterioration caused by discharge of frigid water from Glacial Lake Agassiz, eastward through the Great Lakes to the Goldthwait Sea, in the Gulf of St. Lawrence basin. Here, we gather together geological evidence from widely scattered localities around the Gulf of St. Lawrence, previously reported, some unexplained, and ascribe it to the same climatic deterioration. We interpret the various marine geological contexts as the products of intensified sea-ice conditions 10-8 14C kabp, specifically at 9300 yrbp (9160 yrbp, reservoir corrected), resulting from that meltwater influx. Other truly glacial features in southeastern Canada -- moraine systems and diamictons -- are also referred to this cooling. This is several centuries too young to be correlated with the pre-Boreal Oscillation, but it coincides with one of several eastward overflows of Lake Agassiz.
Bibliography of Canadian Geomorphology