CGRG Bibliography of Canadian Geomorphology
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Author : Barrie, J.V.
Date : 1999
Title : Recent geological evolution and human impact: Fraser Delta, Canada.
Publication : 1999 Canadian Coastal Conference. Royal Roads University, Victoria, British Columbia, May 19-22, 1999.
Issue :
Page(s) :
Abstract
Throughout the Holocene, the river dominated Fraser Delta on the Pacific coast of Canada has prograded by continuous channel switching and avulsion into a deep (> 300 m) basin. However, at the beginning of the 20th century the delta has been modified to provide a navigable channel and port facilities for the city of Vancouver. Now most of the sand brought down by the river (35 % of the sediment load) is removed from the system by dredging. The remaining fine-grained sediment is transported in a plume past the intertidal estuary and northwards into the basin by the dominant flood tidal flow. Two causeways to the south of the main channel and one to the north that cross the intertidal zone to the delta foreslope act as barriers to the dominant northward sediment transport causing estuarine and localized seabed erosion. On the delta foreslope, off the southern causeways, an eroded distributary channel failure complex has been exposed by flood tidal flows that scour the seabed and form northward migrating subaqueous dunes, increasing the delta slope. This, combined with slow sea level rise and seismicity, intensifies the risk of further erosion and instability of the delta, particularly along the delta front and the intertidal estuaries.
Bibliography of Canadian Geomorphology