The Magnesian escarpment is the most westerly of three prominent

escarpments An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations. The terms ''scarp'' and ''scarp face'' are often used interchangeably with ''escar ...

that run north-south in

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake M ...

. All three escarpments are formed by the edges of layers of sedimentary rocks. The easternmost and most prominent escarpment is the

Niagara Escarpment The Niagara Escarpment is a long escarpment, or cuesta, in Canada and the United States that runs predominantly east–west from New York through Ontario, Michigan, Wisconsin, and into Illinois. The escarpment is most famous as the cliff over ...

formed where younger and harder layers of

dolomite Dolomite may refer to: *Dolomite (mineral), a carbonate mineral *Dolomite (rock), also known as dolostone, a sedimentary carbonate rock *Dolomite, Alabama, United States, an unincorporated community *Dolomite, California, United States, an unincor ...

overlay softer sedimentary rocks. The Black River Escarpment is capped by another layer of relatively harder rocks, overlay older softer rocks. The rocks of the Magnesian layer overlay rocks of the

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

Period, the oldest sedimentary rocks that contain fossils.

References

Landforms of Wisconsin Escarpments of the United States {{Wisconsin-geo-stub