The Mississippian Borden Group (sometimes Borden Formation) is a mapped bedrock unit in Kentucky, Indiana, Illinois, Ohio, West Virginia, and Tennessee. It has many members, which has led some geologists to consider it a group (for example in Indiana) rather than a formation (for example in Kentucky).
Fossils
- Scyphozoans: Conularia sp. (from Borden Formation), Paraconularia sp. (from Coral Ridge Member, New Providence Shale)
- Hexactinellid Sponges (from Muldraugh Formation)
- Brachiopods: Orthotetes keokuk (from Borden Formation), Orbiculoidea (from Coral Ridge Member, New Providence Shale)
- Trilobite: Phillibole conkini (Coral Ridge Member, New Providence Formation, Borden Group)
- Cephalopods: Cantabricanites greenei, Polaricyclus ballardensis, Winchelloceras knappi (all from Coral Ridge Member, New Providence Formation, Borden Group), Muenstroceras oweni, M. parallelum, Kazakhstania colubrella, Imitoceras ixion, Masonoceras kentuckiense, Merocanites drostei, Dzhaprakoceras sp., Polaricyclus bordenensis, Winchelloceras allei (all from Nada and Cowbell Members)
- Crinoids: Pachyocrinus aequalis (from Muldraugh Mbr.), Gilmocrinus kentuckyensis (from Muldraugh Mbr.), Rhodocrinites barrisi divergens, Gilbertsocrinus tuberculosus, Gilbertsocrinus typus, Actinocrinites eximius, Actinocrinites scitulus, Blairocrinus protuberatus, Steganocrinus, Uperocrinus pyriformis, Uperocrinus acuminatus, Eretmocrinus cloelia, Macrocrinus konincki, Dorycrinus quinquelobus, Aorocrinus nodulus, Agaricocrinus planoconvexus, Agaricocrinus inflatus, Dichocrinuspocillum Dichocrinus, Paradichocrinus liratus, Platycrinites glyptus, Platycrinites planus, Platycrinities spinifer, Cyathocrinites iowensis, Barycrinus spurious, Costalocrinus cornutus, Meniscocrinus, Pellecrinus obuncus, Atelestocrinus kentuckyensis, Holcocrinus spinobrachiatus, Blothrocrinus swallovi, Coeliocrinus subspinosus, Decadocrinus scalaris, Taxocrinus, Synbathocrinus dentatus, Halysiocrinus dactylus (from Nada Mbr.).
- Blastoids: Granatocrinus kentuckyensis (from New Providence Shale)
A rare soft-bodied fossil that was recovered from the Farmers Member of the Borden Formation in northeastern Kentucky was interpreted as a chondrophorine float (an internal anatomical feature).
Trace fossils
Zoophycos is present in the turbidites of the Farmers Member of the Borden Formation in Kentucky.
Stratigraphy
There are three members of the Borden Group in Indiana.
Edwardsville Formation
The Edwardsville Formation is a geological structure in the Borden Group, of the Lower Mississippian sub system, (Osagean, late Tournaisian). Crinoids fossils can be found in the formation.
New Providence Shale
The New Providence Shale is a geologic formation in Indiana. It is a basal clay-shale geologic formation in Indiana named by Charles Butts and William W. Borden in the 1874 after New Providence, Indiana (now Borden).
Spickert Knob Formation
The Spickert Knob Formation is a geologic formation in Indiana.
External links
- Upper DevonianâÂÂLower Mississippian clastic rocks in northeastern Kentucky: Evidence for Acadian alpine glaciation and models for source-rock and reservoir-rock development in the eastern United States, Ettensohn, F.R., Lierman, R.T., and Mason, C.E., 2009, American Institute of Professional Geologists, Kentucky Section, Spring Field Trip, April 18, 2009
- Matchen, D.L. and T.W. Kammer. 1994. Sequence stratigraphy of the Lower Mississippian Price and Borden Formations in southern West Virginia and eastern Kentucky. SOUTHEASTERN GEOLOGY, 34:25-41. PDF
References
Sources