CGRG Bibliography of Canadian Geomorphology
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Author : Evans, S.G.; and Savigny, K.W.
Date : 1994
Title : Landslides in the Vancouver - Fraser Valley - Whistler region.
Publication : Geology and Geological Hazards of the Vancouver Region, Southwestern British Columbia. Edited by: J.W.H. Monger; Geological Survey of Canada, Bulletin
Issue : 481
Page(s) : 251-286
Abstract
A great diversity of landslide types occur in the Vancouver region in response to high relief, steep slopes, heavy rainfall, seismicity, and a variety of landslide-prone materials. Rockfalls and small rock avalanches (less than a million cubic metres) are a significant hazard to land use development but their biggest impact has been on the transportation network and the Fraser River fishery. The deposits of large rock avalanches (greater than a million cubic metres) are common throughout the region and have occurred along major transportation routes in the Fraser Valley and the Squamish-Pemberton corridor in the last 10,000 years. Noncatastrophic mountain slope deformation is also widespread. Such processes form linear topographic features such as cracks and fissures. Volcanic rocks of the Garibaldi Volcanic Belt are particularly prone to massive rapid landslides, some of which have blocked major rivers and formed temporary lakes upstream. Since the late Pleistocene, major collapses have taken place on the western flanks of Mount Garibaldi and Mount Cayley volcanoes. Large landslides continue to occur in the historical period and are a major consideration in land development in the Belt. Channelized debris flows within steep mountain watersheds triggered by heavy rains occur throughout the region. Debris flow defensive structures have been constructed by provincial authorities at numerous locations to protect transportation routes and/or communities. Landslides in Pleistocene sediments are also important. In addition, a number of cases of catastrophic seepage erosion have been documented. Submarine failures (outside the Fraser Delta) occur on delta fronts in both marine and lacustrine environments. The expansion of development in the Vancouver region is increasing the vulnerability of communities, transportation routes, and the resource base to landslides.
Bibliography of Canadian Geomorphology