A specimen with shatter cones in Ordovician Period limestone from the Central Peak of the Serpent Mound Impact Structure at the William V. Martin farm north of Peebles in Adams County, Ohio. This area has dolomite, shale, limestone, sandstone, and siltstone lithologies. Because of the geologic forces that have acted on the site of the impact crater, bedrock in the area is a mixture of uplifted, down dropped, faulted, folded and eroded rock from the Ordovician, Silurian, Devonian and Mississippian Geologic Periods. The specimen photograph was taken by Gerald H. Newsom related to the American Association of Petroleum Geologists Eastern Section Meeting Field Trip to the Plum Run Quarry and the Serpent Mound Disturbance on October 10, [...]
