Guide to selected geological field sites in Franklin and Delaware Counties, Ohio

Abstract

The city of Columbus and the area to the North of it are rapidly expanding. It is hard to believe that there are still so many geologic sites to be seen in the area. Information on where these sites are located is difficult to find, so this paper will be a guidebook to selected sites of geological interest in Franklin and Delaware Counties. Much of Ohio is covered in glacial till deposited by the last ice age. Areas that are not covered in till, show outcrops of the underlying bedrock. This bedrock ranges in age from Late Silurian to Early Mississippian (410-360 mya). The bedrock units to be studies are, stratigraphically from the oldest to youngest, the Salina Group, the Columbus Limestone, the Delaware Limestone, the Olentangy Shale, the Ohio Shale, the Bedford Shale, the Berea Sandstone, the Sunbury Shale, and the Cuyahoga Formation. The sites chosen to view these units are spread throughout Franklin and Delaware Counties and include many parks as well as some private property such as schools and businesses. Directions and contact information for each site are given.