Decaturville crater, also called the Decaturville Dome, is a roughly 6-kilometer impact crater near Decaturville, Missouri. Unlike many craters, it is exposed at the surface, allowing the impact’s effects to be seen directly in the landscape and bedrock. It is one of the 38th parallel structures, a line of circular geophysical features across the central United States proposed as possible traces of an ancient serial impact event. Thought to date from the Permian or later and be less than 300 million years old, the crater has been closely studied since detailed mapping in the 1970s by T. W. Offield and H. A. Pohn with NASA support.