| Chagrin Shale | |
|---|---|
| Stratigraphic range: Famennian | |
 A fossil in the Chagrin Shale | |
| Type | Formation |
| Unit of | Ohio Shale |
| Underlies | Cleveland Shale, Cussewago Sandstone |
| Overlies | Huron Member |
| Lithology | |
| Primary | Shale |
| Location | |
| Region |  Ohio |
| Country |  United States |
| Type section | |
| Named for | Chagrin River |
| Named by | Charles S. Prosser |
The Chagrin Shale is a shale geologic formation in the eastern United States that is approximately 365 million years old. The Chagrin Shale is a gray shale that begins thin and deep underground in north-central Ohio. As it proceeds east, the formation thickens, rises to the surface, and contains greater amounts of siltstone.