Surficial geology and landslide inventory of the lower Sea to Sky corridor, British Columbia

Abstract

The surficial geology and landslide inventory of the Lower Sea to Sky Corridor provides a record of the late Quaternary history of the map area in southern British Columbia near the edge of the former Cordilleran Ice Sheet. The map depicts a variety of sediment units of glacial and non-glacial origin superposed on a hillshade DEM. From oldest to youngest, the units are bedrock, till, glaciofluvial deposits, glaciomarine deposits, alluvium, colluvium, and organic deposits. Landslides are identified and classified in the colluvium units. Till, was deposited by glacier ice and consists of boulder- to pebble-sized clasts in a matrix of sand, silt, and clay. Glaciofluvial deposits consist of stratified, well sorted to poorly sorted sand and gravel. They are associated with terraces and blankets. Glaciomarine deposits consist of stratified, well sorted to poorly sorted sand, gravel and silty clay muds. They are also fossiliferous in some places. They are associated with terraces and blankets. Alluvium consists of fine silt, sand, and minor gravel deposited along modern streams after deglaciation. Colluvium is derived from bedrock, till, or glaciofluvial deposits that failed. Organic deposits include peat and organic-rich muds that have accumulated in poorly drained depressions formed in older sediments and bedrock.