List of fossiliferous stratigraphic units in Arkansas

Group or Formation	Period	Notes
Annona Chalk	Cretaceous
Arkadelphia Marl	Cretaceous
Austin Chalk	Cretaceous
Batesville Sandstone	Carboniferous
Bloyd Shale	Carboniferous
Boone Formation	Carboniferous
Brownstone Marl	Cretaceous
Cane Hill Formation	Carboniferous
Claiborne Formation	Paleogene
Collier Shale	Cambrian
Comanche Formation	Cretaceous
De Queen Formation	Cretaceous
Dierks Limestone	Cretaceous
Everton Formation	Ordovician
Fayetteville Shale	Carboniferous
Hale Formation	Carboniferous
Hindsville Formation	Carboniferous
Imo Formation	Carboniferous
Jackson Group/White Bluff Formation	Paleogene
Kimmswick Limestone	Ordovician
Marlbrook Marl	Cretaceous
Midway Formation	Paleogene
Moorefield Formation	Carboniferous
Morrow Group/Bloyd Formation	Carboniferous
Nacatoch Formation	Cretaceous
Nacatoch Sand	Cretaceous
Navarro Group/Saratoga Chalk	Cretaceous
Ozan Formation	Cretaceous
Pentremital Limestone Group/Bloyd Formation	Carboniferous
Pitkin Formation	Carboniferous
Powell Formation	Ordovician
Saratoga Chalk	Cretaceous
Smackover Formation	Jurassic
Smithville Formation	Ordovician
St. Clair Limestone	Silurian
St. Joe Formation	Carboniferous
Taylor Group/Annona Chalk	Cretaceous
Taylor Group/Ozan Formation	Cretaceous
Theodosia Formation	Ordovician
Trinity Group/Holly Creek Formation	Cretaceous
Witts Springs Formation	Carboniferous

See also

• Paleontology in Arkansas