- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
For further light on problems in the deformation of the southern Canadian Rockies, a petrographic analysis was made on selected samples from the Gulf Spring Point well in the Foothills region, to determine if any significant differences exist between sediments from the Upper Cretaceous and the Paleocene, which might reflect progressive advance of the source as well as repeated reworking during successive cycles. The intercalated sandstones show nothing to support an hypothesis of migrating foredeeps (Bally et al, 1966); rather, they suggest continuous sediment supply from essentially the same source. Relatively small and gradational changes in composition observed are caused by changes in proportion of rock constituents, not type. This shift is believed to result from progressively deeper erosion in the area of provenance.