| Powell Formation | |
|---|---|
| Stratigraphic range: Ordovician | |
| Type | Formation | 
| Underlies | Everton Formation | 
| Overlies | Cotter Formation [1] | 
| Lithology | |
| Primary | Dolomite | 
| Other | Shale, sandstone, chert | 
| Location | |
| Region | Arkansas, Missouri and Virginia | 
| Country | United States | 
| Type section | |
| Named for | Powell railroad station (now abandoned), Marion County, Arkansas [2] | 
| Named by | Edward Oscar Ulrich | 
The Powell Formation or Powell Dolomite is a geologic formation in northern Arkansas, southeast Missouri [3] and Virginia. It contains gastropod, cephalopod, and trilobite fossils dating back to the Ordovician Period. [3]