| Chico Formation | |
|---|---|
| Stratigraphic range: Campanian Age, Cretaceous Period | |
| Type | Geological formation |
| Underlies | Martinez Formation (regionally), Tejon Formation (regionally) |
| Overlies | Vaqueros Formation |
| Lithology | |
| Primary | sandstone |
| Location | |
| Region | California, Oregon |
| Country | United States |
| Type section | |
| Named for | Chico, California |
The Chico Formation is a geologic formation of the Campanian Age during the Cretaceous Period, found in California and southern Oregon.