Glacial History of the Coteau des Prairies Map showing Coteau

One of the most unique physiographic regions in eastern South Dakota is the Coteau des Prairies. The portion of the Coteau des Prairies in South Dakota measures 100 miles in its greatest width, 200 miles in length, and is composed of glacial sediments from numerous glaciations. These sediments reach a composite thickness of over 900 feet. Ongoing exploratory drilling by the Geological Survey Program of the South Dakota Department of Environment and Natural Resources has established a general characterization of the geology and hydrology of eastern South Dakota. These studies provide a framework for more in-depth studies of the glacial history of the region.

Although much is already known about the glacial history of the area, more work needs to be completed in the areas of Pleistocene stratigraphy, glacio-tectonics, glacial petrology, and geomorphology. Work completed in conjunction with the Geological Survey would contribute significantly to unraveling the glacial history of the Coteau des Prairie in South Dakota. To learn more about the opportunities to collaborate with the Geological Survey Program on this topic, contact Dennis Tomhave (dtomhave@usd.edu) or Layne Schulz (lschulz@usd.edu).

Benefits to South Dakota

Information collected from studies of the Coteau des Prairie will provide data to the public concerning the economic and natural resources in eastern South Dakota (i.e., ground water, sand and gravel, wetland areas, etc.). These studies would be directed at refining our understanding of the glacial geology of a large area of eastern South Dakota. This is important because a large number of aquifers used as sources of drinking water and for irrigation by South Dakota farmers are within the glacial sand and gravel deposits of the Coteau des Prairie. These deposits are also a source of coarse aggregate. Additionally, the sources of water for some of the wetlands on the Coteau des Prairie are aquifers within sand and gravel deposits that are present within this coteau. Currently, the Geological Survey is conducting aquifer delineation studies in the area of the Coteau des Prairie; thus, the possible collaborative studies would also help to further our understanding of aquifers in the area.