| State | Georgia |
|---|---|
| Name | Devonian-Missisippian undivided |
| Geologic age | Devonian-Mississippian |
| Lithologic constituents | Major
Sedimentary > Chemical > Chert
Sedimentary > Clastic > Mudstone > Shale > Black-shale
|
| Comments | Ridge and Valley sedimentary rocks. Secondary unit descriptions from USGS Geologic Names lexicon (ref. GA003): The Fort Payne consists of limestones that are commonly cherty, biostromal, crinoidal, or siliceous. It also contains cherty dolostones and calcareous, cherty siltstones. Age is Early Mississippian. Named Chattanooga black shale. Thickness is 0 to 35 ft. In northwestern GA, underlain by the Rockwood formation and overlain by the Fort Payne chert. Armuchee chert described in northwestern GA as rusty, sandy, bedded chert, at places grading into ferruginous sandstone. Thickness 0 to 50 ft. Underlies Chattanooga shale and overlies Rockwood formation on north side of Coosa Valley, northwest of Coosa fault. Probably contemporary with Frog Mountain sandstone of Oriskany age, which is present only in the southwest corner of Rome quad. |
| References | Lawton, D.E., Moye, F.J., Murray, J.B., O'Connor, B.J., Penley, H.M., Sandrock, G.S., Marsalis, W.E., Friddell, M.S., Hetrick, J.H., Huddlestun, P.F., Hunter, R.E., Mann, W.R., Martin, B.F., Pickering, S.M., Schneeberger, F.J., and Wilson, J.D., 1976, Geologic Map of Georgia, Georgia Dept. of Natural Resources, Geologic and Water Resources Division, Georgia Geological Survey. Scale 1:500,000. |
| NGMDB product | |
| Counties | Catoosa - Chattooga - Dade - Floyd - Gordon - Walker - Whitfield |