Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay
Limestones and shales north of Milwaukee are the only Devonian units in Wisconsin. Some of these contain natural asphalt, the only hydrocarbon occurrence in Wisconsin. Early geologic literature also mentioned a tiny exposure of Mississippian rocks at one locality along the lakeshore.
Created 11 Sep 1997, Last Update 11 January 2020