CGRG Bibliography of Canadian Geomorphology
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Author : Geertsema, M.; and Cruden,D.M.
Date : 2008.
Title : Travels in the Canadian Cordillera.
Publication : 4th Canadian Conference on Geohazards: From Cause to Management. May 20-24, 2008. University Laval, Quebec City, Quebec.
Issue :
Page(s) :
Abstract
The first published prediction of the travel of displaced material in a landslide in the Canadian Cordillera was the Royal Commission's 1911 Map of Turtle Mountain….showing Danger Area. J.R. Boyd, the Commission's surveyor photogrammetrically reconstructed the centre peak that fell and used the plunge of the line from it to the tip of the displaced material to estimate the travel of a block from North Peak. Boyd's peak travel angle is 30% larger than the fahrboschung (or angle of reach) estimated from the crown of the landslide by Heim along the centre line of the displaced material. The travel angle (as defined by Cruden and Varnes) is the simplest index of travel to determine; it approximates the angle of reach. We have measured travel angles for an additional 32 historic landslides in Northern British Columbia; they depend on both modes of movement and on the characteristics of the displaced materials. Flows in sensitive glaciomarine sediments have the lowest travel angles, less than 2 degrees. Other earth flows, in tills derived from shales, may be as low as 7 degrees. Complex landslides in both soil and rock gave angles ranging from 3.5 to 16 degrees. Rock landslides onto glaciers also showed low travel angles, 9.5 to 22 degrees, in comparison to a range of 14 to 30 degrees for rock movements free of ice.
Bibliography of Canadian Geomorphology