Marias River Shale
From Wikipedia, the free encyclopedia
| Marias River Shale | |
|---|---|
| Stratigraphic range: Cretaceous | |
| Type | Formation |
| Location | |
| Region | Montana |
| Country | United States |
The Marias River Shale is a geologic formation in Montana. It preserves fossils dating back to the Cretaceous period.