| Johnson Formation | |
| Type: | Formation |
| Age: | Carboniferous |
| Prilithology: | Shale |
| Otherlithology: | resistant beds of argillaceous mudstone to well-laminated limestones[1] |
| Namedfor: | Johnson, Oklahoma |
| Region: | Midcontinent (Nebraska, Kansas, Oklahoma) |
| Country: | United States |
| Underlies: | Red Eagle Formation |
| Overlies: | Foraker Formation |
The Johnson Formation (or Johnson Limestone) is a thick geologic formation of soft shale with thin, resistant beds of chalkier mudstone and limestone in Nebraska, Kansas, and Oklahoma rarely exposed outside of road cuts. It preserves fossils dating back to the late-Carboniferous period.[2]