CGRG Bibliography of Canadian Geomorphology
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Author : Cummings, D.I.; Russell, H.A.J.; and Sharpe, D.R.
Date : 2011.
Title : The final chapter: Quaternary deposits in the Ottawa-Bonnechere graben (Champlain Sea basin) near Ottawa.
Publication : Joint Annual Meeting of Geological Association of Canada, the Mineralogical Association of Canada, the Society of Economic Geologists and the Society for Geology Applied to Mineral Deposits. May 25-27, 2011. University of Ottawa, Ottawa, Ontario.
Issue :
Page(s) :
Abstract
The Champlain Sea was an inland arm of the Atlantic Ocean that invaded part of the Ottawa-Bonnechere graben following retreat of the Laurentide Ice Sheet. The sea lasted for about two thousand years around the start of the Holocene, its level falling continuously as the crust rebounded isostatically. Although both glacier and sea are now gone, the sediment they left behind preserves a detailed record of the deglacial event history, and remains integral to life in the Lowland. It is farmed extensively, mined for aggregate, and used as a substrate for waste disposal. Buried eskers host abundant supplies of potable groundwater and Champlain Sea mud is prone to slope failure. The Geological Survey of Canada has worked in the Champlain Sea basin for over 100 years, accumulating an extensive body of data and knowledge in the process. Over the past 5 years, a large dataset of cores, outcrop data, and seismic transects has been collected to study mud-buried esker aquifers in the Champlain Sea basin near Ottawa, Canada. The dataset provides new insight into the late Quaternary history of the Ottawa-Bonnechere graben, and, in particular, the contribution of esker sedimentary systems to basin infilling. The objective of this talk is to provide a broad review of the historical development of facts and ideas regarding the Quaternary history of the Ottawa-Bonnechere graben (Champlain Sea basin), then show how the new data advance the existing conceptual framework. Links between graben geometry and Quaternary sedimentation will be discussed; new evidence for catastrophic, proglacial, early Holocene meltwater discharges down the Ottawa-St. Lawrence corridor into the Atlantic Ocean will be presented; and a sequence stratigraphic model tailored for glacial depositional systems will be proposed to explain and unify the litho-, bio-, chemo- and seismic stratigraphic patterns observed in the basin fill.
Bibliography of Canadian Geomorphology