The Horseshoe Canyon Formation is part of the Edmonton Series and is up to 230m in depth. It is Late Campanian to Early
Maastrichtian in age (Edmontonian Land Mammal Age) and is composed of
mudstone,
sandstone, and
carbonaceous shales. There are a variety of environments, which have yielded a diversity of fossil material. The Horseshoe Canyon Formation outcrops extensively in the area of Drumheller, Alberta, as well as further north along the Red Deer River near Trochu, and also in the city of Edmonton. It is overlain by the Battle, Whitemud, and
Scollard formations.
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