Cody Shale
The Cody Shale is a Late Cretaceous geologic formation. It is mapped in Wyoming, Idaho, and Montana.
The formation is described by W.G. Pierce as follows: upper part is buff, sandy shale and thinly laminated buff sandstone; lower part is dark gray, thin-bedded marine shale.
The formation is divided into many members that vary regionally. Alphabetically:
- Ardmore Bentonite Beds
- Belle [Fourche Formation|Belle Fourche Member]
- Carlile Member
- Claggett Member
- Eldridge Creek Member
- Gammon Ferruginous Member
- Greenhorn Calcareous Member
- Niobrara Member
- Sage Breaks Member
- Shannon Sandstone Member
- Steele Member
- Sussex Sandstone Member
- Telegraph Creek Member
- Wallace Creek Tongue