CGRG Bibliography of Canadian Geomorphology
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Author : Bell, T.; Rogerson, R.J.; Klassen, R.A.; and Dyer, A.
Date : 1987
Title : Acoustic survey and glacial history of Adam lake, outer Nachvak Fiord, northern Labrador
Publication : Current Research, Part A, Geological Survey of Canada, Paper
Issue : 87-1A:
Page(s) : 101-110
Abstract
Adams Lake is a 3.9 km-long by 300 m-wide finger lake occupying a glacially overdeepened valley, oriented east-west parallel to Nachvak Fiord, northern Labrador. It is characterized by three basins ranging from 12 to 21 m in depth, separated by distinct barriers between 3 and 6 m below lake level. The most westerly barrier is likely the subaqueous extension of the Tinutyarvik moraine. Analysis of the 3.5 kHz acoustic record of the lake sediments reveals three acoustic units which are tentatively interpreted as representing sedimentary facies related to a glacial/deglacial cycle. Unit A, the lowermost unit, is characterized by a massive structure and reflector-free image and may comprise drift or bedrock. Unit B is acoustically stratified and is interpreted as a proglacial deposit ranging in depositional environment from ice-proximal to ice-distal, towards the east. Subunit B2, interpreted as a coarse clastic deposit, is tentatively related tothe draining of a nearby moraine-dammed lake. Unit C, an acoustically transparent unit with a uniform thickness of approximately 1.5 m, is interpreted as a postglacial lacustrine sediment.
Bibliography of Canadian Geomorphology