| State | Arkansas |
|---|---|
| Name | Trinity Group |
| Geologic age | Early Cretaceous |
| Lithologic constituents |
Major
Sedimentary > Carbonate > Marlstone (Bed)
Sedimentary > Clastic > Sandstone (Bed)
Minor
Sedimentary > Carbonate > Limestone (Lens)
Sedimentary > Chemical > Novaculite (Bed)
Sedimentary > Chemical > Evaporite > Gypsum (Lens)
|
| Comments | Alternating fine qtz. sand and gypsiferous marls with lenticular fossiliferous limestone, gypsum and minor novaculite gravel. Approximatly 2500 ft. thick. Novaculite-similar to chert but characterized by dominance of microcrystalline quartz over chalcedony. |
| Stratigraphic units | De Queen limestone member, Dierks limestone member. |
| References | Dane, C.H.,1929, Upper Cretaceous formations of southwestern Arkansas: Arkansas Geol. Survey Bull.1, 215 pp. |
| NGMDB product | |
| Counties | Howard - Pike - Sevier |