| Cotter Formation Stratigraphic range: Ordovician |
|
|---|---|
| Type | Formation |
| Underlies | Powell Formation |
| Overlies | Jefferson City Formation |
| Lithology | |
| Primary | Dolostone |
| Other | Chert, sandstone, shale |
| Location | |
| Region | Arkansas, Missouri, Virginia |
| Country | United States |
| Type section | |
| Named for | Cotter, Baxter County, Arkansas |
The Cotter Formation is a geologic formation in ArkansasMissouri and in Virginia. It preserves fossils dating back to the Ordovician period.