| Cody Shale | |
| Type: | Sedimentary |
| Age: | Late Cretaceous |
| Period: | Late Cretaceous |
| Prilithology: | shale |
| Namedfor: | Cody, Wyoming |
| Namedby: | C. T. Lupton, 1916[1] |
| Region: | Montana folded belt province, Central Montana uplift, Big Horn basin, Powder River basin, Wind River basin |
| Country: | United States |
| Subunits: | see text |
| Underlies: | Mesaverde Formation |
| Overlies: | Frontier Formation |
| Thickness: | 500-1000 m |
| Extent: | Wyoming, Idaho, Montana |
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.[2]
The formation is divided into many members that vary regionally. Alphabetically:[3]
Certain members rise to formation rank in other areas; for example, the Greenhorn is classified as a formation in a number of states, particularly in Colorado and Kansas.