Rarely are sedimentary rocks lying perfectly flat. Usually they have some dip, or inclination, to the horizontal. When they do, the resultant landforms are often cuestas, which are shown below. The stronger rocks layers form the caprocks while the weaker rock layers (shown in white) are rapidly eroded and form escarpments, or steep slopes. Michigan's cuestas are mostly buried by thick deposits of glacial drift. However, in the UP and along the western and eastern margins of the Michigan basin the Niagara Cuesta, formed on the resistant Niagara Dolomite, is prominent.

  The thick sequence of Silurian (Niagara) dolomite that surrounds, and dips gently under, the Michigan Basin is very resistant to erosion. Therefore, it tends to form a prominent topographic feature (the Niagara cuesta) and it outcrops in many places as high, rocky cliffs. The eroded edge of these rocks forms an escarpment that can be traced almost continuously along the eastern part of Wisconsin, the Upper Peninsula of Michigan, and on east to New York State were Niagara Falls is formed by waters flowing off the Niagara dolomite onto the softer underlying shales. This escarpment is generally referred to as the Niagara Escarpment.

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