by Raymond R. Anderson and Jean Cutler Prior “Peculiar,” “irregular,” and “uncommon,” are words used to describe one class of Iowa rocks — glacial boulders or “erratics.” Geologists define erratics as stones or boulders that have been carried from their place of origin by a glacier and then left stranded by melting ice on bedrock […]
Iowa Geological SurveyA Partner of IIHR—Hydroscience & Engineering
