| State | Arkansas |
|---|---|
| Name | Tokio Formation |
| Geologic age | Late Cretaceous |
| Lithologic constituents |
Major
Sedimentary > Clastic > Sandstone (Bed)
Sedimentary > Clastic > Mudstone (Bed)
Minor
Sedimentary > Chemical > Novaculite (Bed)
Sedimentary > Coal (Bed)
|
| Comments | Intertouging beds of gray clay and qtz. sand with some lignite and basal novaculite gravels. Approximatly 300 ft. thick. Novaculite-similar to chert but characterized by dominance of microcrystalline quartz over chalcedony. |
| References | Dane, C.H.,1929, Upper Cretaceous formations of southwestern Arkansas: Arkansas Geol. Survey Bull.1, 215 pp. |
| NGMDB product | |
| Counties | Clark - Hempstead - Howard - Little River - Pike - Sevier |