Chickasha Formation

Chickasha Formation
Stratigraphic range: Roadian
TypeFormation
Location
RegionOklahoma
CountryUnited States
Type section
Named forChickasha, Grady County, Oklahoma
Named byCharles Newton Gould, 1924

The Chickasha Formation, which is part of the El Reno Group, is a geologic formation in Oklahoma. It preserves fossils dating back to the Roadian stage of the Middle Permian. These include, among others, the dissorophoid temnospondyl Nooxobeia gracilis, the lepospondyl Diplocaulus parvus (Amphibia: Nectridea), and the captorhinid Rothianiscus robusta, initially called Rothia robusta by Everett C. Olson. Many of these fossils were indicated to have come from the Flowerpot Shale, but these actually come from the Chickasha Formation, according to the current nomenclature. The age of the formation was long debated because Olson based part of his argument on fragmentary fossils that he interpreted as therapsids, an interpretation that was not widely accepted. Worse, one of them, Watongia, was later shown to be a varanopid.

See also

References

  1. ↑ Gould, Charles N. (1924). "A new classification of the Permian redbeds of southwestern Oklahoma". American Association of Petroleum Geologists Bulletin. 8 (3): 322–341.
  2. ↑ Laurin, Michel; Hook, Robert W. (2022). "The age of North America's youngest Paleozoic continental vertebrates: a review of data from the Middle Permian Pease River (Texas) and El Reno (Oklahoma) Groups". BSGF - Earth Sciences Bulletin. 193: 10. doi:10.1051/bsgf/2022007. ISSN 1777-5817.
  3. ↑ Gee, Bryan M.; Scott, Diane; Reisz, Robert R. (October 2018). "Reappraisal of the Permian dissorophid Fayella chickashaensis". Canadian Journal of Earth Sciences. 55 (10): 1103–1114. doi:10.1139/cjes-2018-0053.
  4. ↑ Olson, Everett C. (1972). "Diplocaulus parvus n. sp. (Amphibia: Nectridea) from the Chickasha Formation (Permian: Guadalupian) of Oklahoma". Journal of Paleontology. 46 (5): 656–659. ISSN 0022-3360.
  5. ↑ Olson, E. C. (1965). "New Permian Vertebrates from the Chickasha Formation in Oklahoma". New Permian Vertebrates from the Chickasha Formation in Oklahoma. 70: 1–70.
  6. ↑ Smith, Gary E. (1974). "Depositional systems, San Angelo Formation (Permian), north Texas--facies control of red-bed copper mineralization". Report of Investigations, Bureau of economic geology. 80: 73. doi:10.26153/tsw/4807.
  7. ↑ Olroyd, Savannah L.; Sidor, Christian A. (1 August 2017). "A review of the Guadalupian (middle Permian) global tetrapod fossil record". Earth-Science Reviews. 171: 583–597. doi:10.1016/j.earscirev.2017.07.001. ISSN 0012-8252.
  8. ↑ Olson, E.C. (1974). "On the Source of Therapsids". Annals of the South African Museum. 64: 27–46.
  9. ↑ Reisz, Robert R; Laurin, Michel (1 April 2004). "A reevaluation of the enigmatic Permian synapsid Watongia and of its stratigraphic significance". Canadian Journal of Earth Sciences. 41 (4): 377–386. doi:10.1139/e04-016. ISSN 0008-4077.