| Big Clifty Formation | |
| Type: | Formation |
| Age: | Mississippian |
| Period: | Mississippian |
| Region: | Indiana |
| Country: | United States |
| Unitof: | Stephensport Group |
| Underlies: | Haney Limestone |
| Overlies: | Beech Creek Limestone |
The Big Clifty Formation is a geologic formation in Indiana.[1] It preserves fossils dating back to the Carboniferous period.[2]
In Illinois and Kentucky, the Big Clifty is referred to as the Big Clifty Sandstone and has been assigned to the Golconda Formation.[3]