The Iowa Geoscience Education Information Network

Explore Iowa Geology

Iowa's Bedrock

Iowa's Bedrock Map - You can find the detailed text descriptions of the 2010 Iowa Bedrock Map HERE. The map legend below relate geologic period to each color. Geologic maps are the product of thousands of field and lab work hours. Geologist study and learn from rock outcrops and the Earth's surface and from drill/cores. Since Iowa is covered by glacial sediment and productive soils, the majority of our state's geology knowledge comes from core data. Cores are taken for a variety of reasons including the recovery of drinking water, oil, natural gas and many other applications. You can learn more about Iowa Geologic cores from this Iowa Rock Library, located at the U of I's Oakdale Campus, video and the Iowa Geologic Survey's GeoCore App.

Stratigraphy is a branch of geology that characterizes and communicates the biological, chemical and physical properties of our bedrock layers beneath the state and beyond.