Abstract

The Drumheller-Morrin Area is underlain by Upper Cretaceous and Tertiary marine, brackish-water and continental sediments, dipping very gently to the west into the Alberta syncline. The bedrock is obscured by two till sheets and a disintegration moraine, which includes central-depression prairie mounds, moraine plateaus, and disintegration ridges. Extensive Pleistocene lake deposits accumulated in three lake stages at successively lower levels. The rapid down-cutting by the Red Deer River, probably in post-glacial time, is thought to be the result of an increased discharge due to diversion of the present headwaters of the Red Deer River into the present system north of the town of Red Deer. Rapid erosion of the nonresistant Edmonton formation exposed in the valley walls resulted in the formation of spectacular badlands which are undergoing further erosion at the present time.