Red Rock Coulee

Geological Features

Red Rock Coulee has a diversity of features from bare arid slopes, to native grasslands and plateau.  The main feature is a large area of exposed bearpaw shale out of which appear dozens of sandstone concretions.  These spheroids range in size from 1.5 to 2.5 metres in diameter and are expose to varying degrees from the bedrock.

These concretions were formed in the very sediments upon which they sit.  The process by which concretions are formed leaves them harder and more resistant to erosional forces than the surrounding material. When the parent material erodes the spheres are left exposed and then they in turn begin to erode.