Atoka Formation Explained

Atoka Formation
Type:	Geologic formation
Age:	Pennsylvanian
Prilithology:	Sandstone
Otherlithology:	Shale
Namedby:	J.A. Taff^[1]
Region:	Arkansas, Oklahoma
Country:	United States
Underlies:	Hartshorne Sandstone
Overlies:	Bloyd Formation, Johns Valley Formation

Named after Atoka County, Oklahoma, the Atoka Formation is a geologic formation in central and western Arkansas, eastern Oklahoma, central and western Texas, and eastern New Mexico.^[2] It is the surface rock of the Boston Mountains and dominates exposures in the Frontal Ouachita Mountains of the Arkansas River Valley.^[2]

Sedimentology

The Atoka Formation is a sequence of marine sandstones, siltstones, and shales, and may be as thick at 25,000 feet in the Ouachita Mountains.^[2] The formation is conformable with the Bloyd Shale in the Boston Mountains and the Johns Valley Formation in the Ouachita Mountains.^[2]

Paleofauna

Conodonts

• Cavusgnathus

C. lauta^[3]

C. sinuata^[4]

• Gnathodus

G. wapanuckensis^[5]

• Gondolella

G. bella^[6]

• Hindeodella^[7]
• Ligonodina

L. lexingtonensis^[8]

• Ozarkodina

O. recta^[9]

• Polygnathodella

P. attenuata^[10]

P. ouachitensis^[11]

• Streptognathodus

S. cancellosus^[12]

S. gracilis^[13]

Foraminifera

• Fusulinella

F. devexa^[14]

F. oliviformis^[15]

F. prolifica^[16]

• Hyperammina

H. bulbosa^[17]

• Involutina

I. semicronstrictus^[18]

• Pesudostaffella

P. atokensis^[19]

• Profusulinella

P. fittsi^[20]

P. millcreekensis^[21]

• Reophax

R. fittsi^[22]

R. tumidulus^[23]

• Thurramminoides

T. sphaeroidalis^[24]

Trace Fossils

• Conostichus

C. arkansanus^[25]

Notes and References

1. Taff. J.A.. Adams. G.I.. Geology of the eastern Choctaw coal field. Twenty-First Annual Report of the United States Geological Survey, 1899-1900, Part 2, General Geology, Economic Geology, Alaska. 1900. 272, 273–274.
2. Web site: Stratigraphic Summary of the Arkansas River Valley and Ouachita Mountains. Arkansas Geological Survey. 2017-11-23. 2018-05-29. https://web.archive.org/web/20180529114957/http://www.geology.ar.gov/geology/strat_arkvalley_ouachita.htm. dead.
3. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
4. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
5. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
6. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
7. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
8. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
9. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
10. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
11. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
12. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
13. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
14. Thompson. M.L.. Studies of American fusulinids. University of Kansas Paleontological Contributions, Protozoa. 1948. 1. 184.
15. Douglass. R.C.. Nestell. M.K.. Fusulinids of the Atoka Formation, lower-middle Pennsylvanian, south-central Oklahoma. Oklahoma Geological Survey Bulletin. 1984. 136. 19-39. 7 June 2024.
16. Thompson. M.L.. Fusulinids from the lower Pennsylvanian Atoka and Boggy formations of Oklahoma. Journal of Paleontology. 1935. 9. 291-306.
17. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
18. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
19. Thompson. M.L.. The fusulinid genus Staffella in America. Journal of Paleontology. 1935. 9. 111-120.
20. Thompson. M.L.. Fusulinids from the lower Pennsylvanian Atoka and Boggy formations of Oklahoma. Journal of Paleontology. 1935. 9. 291-306.
21. Douglass. R.C.. Nestell. M.K.. Fusulinids of the Atoka Formation, lower-middle Pennsylvanian, south-central Oklahoma. Oklahoma Geological Survey Bulletin. 1984. 136. 19-39. 7 June 2024.
22. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
23. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
24. Book: Johansson, F. C. Jr. . Micropaleontology of the Wesley Johns Valley and Atoka Formations of the Ouachita Mountains of Oklahoma (PhD. dissertation) . University of Wisconsin . 1960 . 45.
25. Branson. Carl C.. New records of the Scyphomedusan Conostichus. Oklahoma Geology Notes. May 1961. 21. 5. 130–138. 28 January 2018.