CGRG Bibliography of Canadian Geomorphology
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Author : Andrews, J.T.
Date : 1973.
Title : Late Quaternary variations in oxygen and carbon isotopic compositions in Canadian Arctic marine bivalves.
Publication : Palaeogeography, Palaeoclimatology, Palaeoecology
Issue : 14:
Page(s) : 187-192
Abstract
The oxygen and carbon isotopic composition of arctic marine bivalves Mya truncata, Hiatella arctica, and Mytilus edulis are reported on samples from raised marine deposits in Hudson Bay and Baffin Island. The shells range in age from modern, through the Holocene, to "old" marine units. During the Holocene the 180/160 ratio in shells rose to a maximum about 3500 BP which coincides in time with the period of maximum growth rates of blvalves, maxlmum size and maximum faunal diversity . The change is interpreted to indicate that about 3500 years ago arctic waters may have reached a salinity ~1-2% greater than present. Comparison of Holocene shell-carbonate isotopic compositions with those from the "old~ marine shells (that are characteristically extremely thlck) suggests that during the early Wisconsin advance on eastern Baffin Island, surface and near-surface waters were more saline than at present. This may have been related to low meltwater discharge. Paradoxically, positive values of 180/160 and 130/12O in marine shells occurred during the Holocene marine optimum and during the early Wisconsin ice advance.
Bibliography of Canadian Geomorphology