| St. Joe Limestone Member | |
| Type: | Member |
| Age: | Mississippian |
| Prilithology: | Limestone |
| Otherlithology: | Chert |
| Namedfor: | St. Joe, Searcy County, Arkansas |
| Namedby: | T.C. Hopkins[1] |
| Region: | Arkansas, Missouri, Oklahoma |
| Country: | United States |
| Unitof: | Boone Formation |
| Overlies: | Chattanooga Shale |
| Thickness: | up to 100 ft. |
The St. Joe Formation or St. Joe Limestone Member is a geologic formation or member in northern Arkansas, southern Missouri and northeastern Oklahoma. It preserves fossils of the Mississippian subperiod including crinoids, brachiopods, bryozoa, conodonts, blastoids, ostracods and rugose coral.[2]