Fort Payne Formation — Fort Payne Formation
Fort Payne Formation James St. John, Wikimedia Commons, CC BY 2.0

Formation · Carboniferous

Fort Payne Formation

Mississippian unit, Tennessee · Alabama · Kentucky · Georgia

The Fort Payne Formation of Tennessee, Kentucky and Alabama is the Lower Mississippian cherty limestone whose crinoid mounds produce complete crowns of Agaricocrinus, Actinocrinites and Platycrinites, plus blastoids, the screw-shaped bryozoan Archimedes and Spirifer brachiopods. It is one of the two great crinoid sources of the US Midcontinent alongside the Burlington–Keokuk beds of Iowa and Missouri. Complete crowns with stems are valuable; check that the crown and stem belong together and that arms have not been sculpted.

CountryUnited States
RegionTennessee, Alabama, Kentucky, Georgia
AgeTournaisian, Mississippian
Age range~352–340 Ma
Macrostrat rankFm· Macrostrat
Macrostrat age353–341 Ma· Macrostrat
Lithologychert, limestone, carbonate, siltstone, dolomite, silt· Macrostrat
Environmentinferred marine, marine· Macrostrat
Macrostrat columns8 column(s) sampled from 8 unit(s)· Macrostrat
PBDB collections85 collections, 1112 occurrences· Paleobiology Database

Collecting and legality

Fort Payne crinoid beds along Lake Cumberland and the Tennessee River valley are on Corps of Engineers, TVA and private land; Corps lakeshore collecting of common invertebrates is generally tolerated for personal use but not for sale, and Tennessee state law reserves fossils on state land. Crinoid crowns in trade come from private quarries and old collections.

Lithology and setting

Cherty limestone, calcareous shale and crinoidal packstone mounds of a Mississippian carbonate ramp.

Commonly recorded taxa (PBDB)

Genera most often recorded from this unit in the Paleobiology Database (first 200 occurrences): Agaricocrinus (26), Bryozoa (11), Cladochonus (7), Australosutura (6), Cleiothyridina (6), Cypricardinia (6), Dielasma (6), Fenestella (6), Fenestrata (6), Hustedia (6), Ostracoda (6), Porifera (6), Punctospirifer (6), Quadratia (6), Rugosochonetes (6).

Source: Paleobiology Database

Elsewhere

Cite this article

Stratum Study. "Fort Payne Formation" (Formation). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/formations/fort-payne-formation. Accessed 2026-09-20.

@misc{stratum-fort-payne-formation,
  title        = {Fort Payne Formation},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/formations/fort-payne-formation}},
  year         = {2026},
  note         = {Formation article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, macrostrat, pbdb, wikidata, commons. Accessed 2026-09-20.}
}

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