Kope Formation
Kope Formation Stratigraphic range: Katian[1] | |
---|---|
Type | sedimentary |
Unit of | Maquoketa Group (in Indiana) |
Sub-units | Grand Avenue Member, Wesselman Tongue |
Underlies | Dillsboro Formation and Fairview Formation |
Overlies | Lexington Limestone, Plattin Formation, and Point Pleasant Formation |
Lithology | |
Primary | Shale |
Other | Limestone |
Location | |
Region | Cincinnati Arch of North America |
Extent | Kentucky, Ohio, Indiana |
The Kope Formation is one of the three component bedrock formations of the Maquoketa Group that primarily consists of shale (75%) with some limestone (25%) interbedded. In general, it has a bluish-gray color that weathers light gray to yellowish-gray and it occurs in northern Kentucky, southwest Ohio, and southeast Indiana, United States.
Description[]
Depositional environment[]
The depositional environment of the Kope was shallow marine. The central North American continent was a tropical epeiric sea at the time.
Jennette and Pryor (1993) interpret the Kope, along with the Bellevue and Fairview Formations, as a progradational succession on a carbonate ramp. The Kope is the most distal facies of the ramp complex.[2]
Notable outcrops[]
The type section of the Grand Avenue Member is a cliff to the west of Grand Avenue in Cincinnati, Hamilton County, Ohio.[3]
The type section of the Wesselman Tongue of the Kope Formation is an east-facing embankment on an unnamed creek that is followed by Wesselman Road in Miami Township, Hamilton County, Ohio. The embankment is 400 feet (120 m) south of Zion Hill bridge.[3]
Fossil content[]
Brachiopods, trilobites, bryozoans, rugose corals, and echinoderms (including crinoids, asteroids, and edrioasteroids) are all present in the Kope. Due to their mid-continent depositional environment, the fossils are almost free of deformation caused by tectonic activity common in the Appalachian Mountains.
The brachiopods sp., sp., Leptaena sp., Petrocrania sp., sp., Platystrophia sp., sp., Rafinesquina sp., Sowerbyella sp., Strophomena sp., sp., and sp. have been recorded from the Cincinnatian Series, which includes the Kope Formation.[4]
The trilobites such as Triarthrus eatoni, Cryptolithus tessellatus, and have been identified in the Kope, and the Ohio State Fossil, Isotelus maximus, can most likely be found in it.[5]
The bryozoans sp., Eridotrypa mutabilis, , , Dekayia aspera, , sp., and Amplexopora septosa have been found in the Kope.[6]
Among echinoderms, the crinoids , sp., and Iocrinus sp. are present in the Kope. Edrioasteroids and asteroids (starfish), generally rare, are common in overlying formations, and may be present in the Kope.[7]
Age[]
Relative age dating of the Kope places it in the Late Ordovician period.
References[]
- ^ https://etd.ohiolink.edu/!etd.send_file?accession=ucin1322052575&disposition=inline[dead link]
- ^ Jennette, D.C., and Pryor, W.A., 1993, Cyclic alternation of proximal and distal storm facies; Kope and Fairview Formations (Upper Ordovician), Ohio and Kentucky: , v. 63, no. 2, p. 183-203.
- ^ a b Ford, J.P., 1967, Cincinnatian geology in southwest Hamilton County, Ohio: American Association of Petroleum Geologists Bulletin, v. 51, no. 6, p. 918-936.
- ^ Fossils of Ohio, p. 216-18
- ^ Fossils of Ohio, Fig. 8.1
- ^ Fossils of Ohio, Fig. 15.1, Fig. 15.2, Fig. 15.3
- ^ Fossils of Ohio, p. 245-246
Bibliography[]
- Fossils of Ohio, Bulletin 70, Ohio Department of Natural Resources, Division of Geological Survey, Edited by Rodney M. Feldmann and Merrianne Hackathorn, 577 p., 232 plates (some in color), drawings, maps, and tables, 1996.
- Geologic formations of Indiana
- Geologic formations of Kentucky
- Geologic formations of Ohio
- Upper Ordovician Series
- Ordovician System of North America
- Ordovician Ohio
- Ordovician Kentucky
- Ordovician Indiana
- Ordovician south paleopolar deposits
- Ordovician southern paleotemperate deposits
- Limestone formations of the United States
- Shallow marine deposits
- Fossiliferous stratigraphic units of North America
- Paleontology in Indiana
- Paleontology in Kentucky
- Paleontology in Ohio
- Katian