Tuesday, November 30, 2004
Geology and Astronomy: Iowa's Manson Impact Structure
Did you know a crater 24 miles in diameter lies hidden by glacial sediment under crop fields centered in Pocahontas County. This Impact occured over 70 million years ago and most likely killed everything within 850 miles of the impact site.
Iowa's Manson Impact Structure by Raymond R. Anderson
More Manson Impact Structure References From the Earth Impact Database