CGRG Bibliography of Canadian Geomorphology
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Author : Barrie, C.Q.; and Piper, D.J.W.
Date : 1982
Title : Late Quaternary marine geology of Makkovik Bay, Labradoe
Publication : Geological Survey of Canada, Paper
Issue : 81-17
Page(s) : 1-37
Abstract
Three major surficial units are recognizable ... lower basin-fill, conformable cover and upper basin-fill units. The lower basin-fill unit ... [was] probably deposited prior to 11,000 years B.P. The conformable cover unit is acoustically well stratified and mantles the entire bay, .... The distribution of benthonic foraminifera suggests a high rate of sedimentation in an open bay environment. The conformable cover unit is interpreted to have had runoff-dominated deposition from suspension occurring during the last major transgression terminating at approximately 10,000 years B.P. Glacial detritus was transported fluvially northwards along the Makkovik Brook and nearby valleys and distributed across Makkovik Bay within the upper fresher water layer of a well stratified two-layer type estuary. Rapid deposition occurred through the lower, more saline water layer. The upper basin-fill unit is characterized by poor acoustic reflectivity and aponded depositional style with a variable degree of onlap which is inversely related to wave energy. ... The lithologies change upwards from alternating olive-grey and yellow-brown muds through grey-brown to dark greyish-olive muds. The sedimentation rate decreases upwards from approximately 0.3 to 0.07 cm/year. At the base of the upper basin-fill unit benthonic foraminifera indicate open bay conditions, but become progressively more estuarine upwards. The transition to wave-dominated deposition occurs earlier in the Approaches than the Outer Bay; it is controlled by runoff and the relative sea level. An erosional unconformity occurs within the upper basin-fill unit, at approximately 6500 years B.P., during the Holocene hypsithermal, and may be related to increased storm wave action or to renewed activity after a brief period of suspension dominated deposition.
Bibliography of Canadian Geomorphology