Earth:Chakpaktas Formation

From HandWiki
Chakpaktas Formation
Stratigraphic range: Middle Eocene,
Arshantan
↓
TypeFormation
Unit ofZaysan Depression
UnderliesObaila Formation
Thickness29 metres (95 ft)
Lithology
Primarymudstone, sandstone
Location
Country Kazakhstan

Chakpaktas Formation (also known as the Chakpaktas svita) is a geological formation in eastern Kazakstan, as well as being the lowest fossil-bearing strata of the Zaysan Depression. The formation is aged to the Arshantan Asian Land Animal Age which correlates to between the upper Ypresian and lower Lutetian.[1][2]

Geology

The Chakpaktas formation is made up of 29 meters of deposits with the sediment transitioning from mudstone to sandstone around midway through.[3] It contains interbedding of quartz and pebbles at the lower parts of the deposit.[4] The mammal localities of the formation can only be found in the southeastern part of the basin which falls in between the Kalmakpay Mountain and Kendyrlyk River.[5]

Paleobiota

Artiodactyla

Genus Species Notes Image
Aksyiria[6] A. oligostus A poorly known dichobunid known from a single molar.[7]
Paraphenacodus[6] P. solivagus A large dichobunid known from a single lower molar that shows a bunodont morphology.[7]

Crocodilia

Genus Species Notes Image
Pristichampsus [4] P. kuznetsov A more terrestrial crocodilian, the genus is of questionable validity as some species have been moved to other genera.[8] It is not completely known where the material attributed to the species is found, though it is most likely to have come from the Chakpaktas Formation.[4]

Dinocerata

Genus Species Notes Image
Gobiatherium[3] G. mirificum A long-skulled uintathere with an inflated nasal region and flared zygomatic arches similar in shape to what's seen in entelodonts.[3] frameless

Perissodactyla

Genus Species Notes Image
Eoletes[9] E. tshakpaktasensis A hyrachyid known from a fairly complete skull, larger than other species within the genus like E. tianshanicus. It was originally described as the genus Subhyrachyus.[9]
Isectolophus[1] I. latidens An isectolophid perissodactyl that helped to confirm the correlation between the Arshantan and Bridgerian land animal ages. The animal lacked the postcanine diastema seen in most ungulates.[1]
Rhodopagus[9] "R". radinskyi A hyracodontid that has been noted to be within its own genus rather than being assigned to the genus Rhodopagus.[9]

Rodentia

Genus Species Notes Image
Juniperimus[10] J. flerovi

Testudine

Genus Species Notes Image
Altaytrionyx[4] A. devjatkini A trionychid turtle.[11]
Geiselemys[4] G. sp. A geoemydid turtle that was originally described under the genus grayemys.[12]
Paraplastomenus[4] P. cf. mlynarskii A medium-sized trionychid with a large amount of medial contact of the hyopastra and hypoplastra.[13]

References

  1. ↑ 1.0 1.1 1.2 Lucas, Spencer G.; Holbrook, Luke T.; Emry, Robert J. (2003-04-11). [238:impfte2.0.co;2 "Isectolophus(Mammalia, Perissodactyla) from the Eocene of the Zaysan Basin, Kazakstan and its biochronological significance"]. Journal of Vertebrate Paleontology 23 (1): 238–243. doi:10.1671/0272-4634(2003)23[238:impfte2.0.co;2]. ISSN 0272-4634. http://dx.doi.org/10.1671/0272-4634(2003)23[238:impfte]2.0.co;2. 
  2. ↑ Paepen, Marieke; Li, Hong; Sun, Yan; Smith, Thierry (July 2021). "A late early to early middle Eocene mammal assemblage from Bayan Ulan (Inner Mongolia, China): Implication for the reassessment of the Arshantan Asian Land Mammal Age". Geobios 66-67: 177–191. doi:10.1016/j.geobios.2020.11.001. ISSN 0016-6995. Bibcode: 2021Geobi..66..177P. http://dx.doi.org/10.1016/j.geobios.2020.11.001. 
  3. ↑ 3.0 3.1 3.2 Lucas, Spencer G. (February 2001). "Gobiatherium (Mammalia: Dinocerata) from the Middle Eocene of Asia: Taxonomy and biochronological significance". Paläontologische Zeitschrift 74 (4): 591–600. doi:10.1007/bf02988166. ISSN 0031-0220. Bibcode: 2001PalZ...74..591L. http://dx.doi.org/10.1007/bf02988166. 
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Trikhunkov, Ya. I.; Tesakov, A. S.; Bachmanov, D. M.; Syromyatnikova, E. V.; Latyshev, A. V.; Bulanov, S. A.; Azelkhanov, A. Zh.; Suyekpaev, E. S. (2023-11-15). "Stratigraphy of Cenozoic Deposits and the History of the Latest Stage of Geological Development of the Zaisan Depression (Eastern Kazakhstan)". Stratigraphy and Geological Correlation 31 (6): 612–631. doi:10.1134/s0869593823060126. ISSN 0869-5938. Bibcode: 2023SGC....31..612T. http://dx.doi.org/10.1134/s0869593823060126. 
  5. ↑ Lucas, Spencer G.; Bray, Emily S.; Emry, Robert J.; Hirsch, Karl F. (April 2012). "DINOSAUR EGGSHELL AND THE CRETACEOUS-PALEOGENE BOUNDARY IN THE ZAYSAN BASIN, EASTERN KAZAKSTAN". Journal of Stratigraphy 36 (2). https://www.researchgate.net/publication/234058967. 
  6. ↑ 6.0 6.1 Averianov, Alexander (1996). "Artiodactyla from the early Eocene of Kyrgyzstan". Zoological Institute of the Russian Academy of Sciences 25 (2–4): 359–369. https://www.researchgate.net/publication/317332987. 
  7. ↑ 7.0 7.1 Prothero, Donald (2007). The Evolution of Artiodactyls. Johns Hopkins University Press. doi:10.56021/9780801887352. ISBN 978-0-8018-8735-2. http://dx.doi.org/10.56021/9780801887352. 
  8. ↑ Brochu, Christopher A. (September 2012). "Phylogenetic relationships of Palaeogene ziphodont eusuchians and the status ofPristichampsusGervais, 1853". Earth and Environmental Science Transactions of the Royal Society of Edinburgh 103 (3–4): 521–550. doi:10.1017/s1755691013000200. ISSN 1755-6910. Bibcode: 2012EESTR.103..521B. http://dx.doi.org/10.1017/s1755691013000200. 
  9. ↑ 9.0 9.1 9.2 9.3 Averianov, Alexander; Godinot, Marc (2005). "Ceratomorphs (Mammalia, Perissodactyla) from the early Eocene Andarak 2 locality in Kyrgyzstan". Geodiversitas 27 (2): 221–237. https://doc.rero.ch/record/16023/files/PAL_E3802.pdf. 
  10. ↑ Li, Qian; Meng, Jin (2015-03-20). "New Ctenodactyloid Rodents from the Erlian Basin, Nei Mongol, China, and the Phylogenetic Relationships of Eocene Asian Ctenodactyloids". American Museum Novitates (3828): 1–20. doi:10.1206/3828.1. ISSN 0003-0082. http://dx.doi.org/10.1206/3828.1. 
  11. ↑ Georgalis, Georgios L.; Joyce, Walter G. (April 2017). "A Review of the Fossil Record of Old World Turtles of the CladePan-Trionychidae". Bulletin of the Peabody Museum of Natural History 58 (1): 115–208. doi:10.3374/014.058.0106. ISSN 0079-032X. http://dx.doi.org/10.3374/014.058.0106. 
  12. ↑ Claude, Julien; Zhang, Jiang-Yong; Li, Jian-Jun; Mo, Jin-You; Kuang, Xue-Wen; Tong, Haiyan (2012-12-01). "Geoemydid turtles from the Late Eocene Maoming basin, southern China". Bulletin de la Société Géologique de France 183 (6): 641–651. doi:10.2113/gssgfbull.183.6.641. ISSN 1777-5817. http://dx.doi.org/10.2113/gssgfbull.183.6.641. 
  13. ↑ Vitek, Natasha T.; Danilov, Igor G. (March 2010). "New Material and a Reassessment of Soft-Shelled Turtles (Trionychidae) from the Late Cretaceous of Middle Asia and Kazakhstan". Journal of Vertebrate Paleontology 30 (2): 383–393. doi:10.1080/02724631003617548. Bibcode: 2010JVPal..30..383V. https://www.jstor.org/stable/pdf/40666162.pdf. 



Retrieved from "https://handwiki.org/wiki/index.php?title=Earth:Chakpaktas_Formation&oldid=3999240"