Giant Ancient Impact Crater Confirmed in Iowa

3-D perspective map of the Decorah impact feature looking northward. (Credit: USGS/Adam Kiel graphic/Northeast Iowa RC&D).

A monster lurks under northeastern Iowa. That monster is in the form of a giant buried basin, the result of a meteorite impact in central North America over 470 million years ago.

A recent aerial survey conducted by the state of Minnesota Geological Survey and the United States Geological Survey (USGS) confirms the existence of an impact structure long suspected near the eastern edge of the town of Decorah, Iowa. The goal of the 60 day survey was a routine look at possible mineral and water resources in the region, but the confirmation of the crater was an added plus. Continue reading “Giant Ancient Impact Crater Confirmed in Iowa”