CGRG Bibliography of Canadian Geomorphology
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Author : Eyles, N.; Buergin, R.; and Hincenbergs, A.
Date : 1986
Title : Sedimentological controls on piping structures and the development of scalloped slopes along an eroding shoreline; Scarborough Bluffs, Ontario
Publication : Proceedings Symposium on Cohesive Shores, May 5-7, 1986, Burlington, Ontario. Edited by: M.G. Skafel. Associate Committee for Research on Shoreline Erosion and Sedimentation. National Research Council Canada.
Issue : NRCC 26134
Page(s) : 60-68
Abstract
Scarborough Bluffs, along the lake Ontario shoreline east of Toronto, currently represent the most intractable erosion problem in Canada given the length of the shoreline (16 km), geological complexity and proximity to urban development. Erosion rates average between 1 and 2 m yr-1. Large scallops and ravines add a third dimension to the problem resulting in a total length of active slope of 33 km with slopes ranging in height from 10 to 85 m. The bluff stratigraphy consists of Late Pleistocene sandy deltaic facies alternating in layer cake fashion with fine-grained diamicts (pebbly mud) facies resulting in strong permeability contrasts. Pipe structures develop where groundwater seepage is focused by sand filled basins on the upper surface of the diamicts. Basins formed by loading as storm-emplaced deltaic sands prograded across soft pebbly muds on the lake floor. Scallops result from the collapse of pies and subsequent focusing of surface runoff. Scalloped slopes erode headward at rates of up to 4 m yr-1.
Bibliography of Canadian Geomorphology