The Ulan Malgait Formation is a Late Jurassic geologic formation in Mongolia. Dinosaur remains are among the fossils that have been recovered from the formation, although as of 2004[update] none have yet been referred to a specific genus.[1]
| Ulan Malgait Formation | |
|---|---|
| Stratigraphic range: Tithonian or Oxfordian ~ | |
| Type | Geological formation |
| Sub-units | Shar Teg & Ulan Malgait Beds |
| Thickness | up to ~300 m (980 ft) |
| Lithology | |
| Primary | Mudstone |
| Other | Sandstone, conglomerate, caliche |
| Location | |
| Coordinates | 44°06′N 95°48′E / 44.1°N 95.8°E |
| Approximate paleocoordinates | 46°00′N 98°00′E / 46.0°N 98.0°E |
| Region | Govi-Altay |
| Country |  Mongolia |
| Type section | |
| Named for | Ulan Malgait Mountain |
  Ulan Malgait Formation (Mongolia) | |
It is best known for the Shar Teeg locality which has lent its name to Shartegosuchidae, a family of mesoeucrocodylians (relatives of crocodilians), many of which have been found there; Shartegosuchus (the family's type genus) means "Shar Teeg crocodile".[2] It is divided up into 2 subunits, the lower Shar Teg Beds and the upper Ulan Malgait Beds.[3]
The tritylodontids Shartegodon, Nuurtherium and Bienotheroides are known from the formation.,[4] As is docodontan Tegotherium. The turtles Annemys levensis and Annemys latiens and crocodylians Sunosuchus shartegensis and Adzhosuchus fuscus were also recovered from the formation.[5] Numerous species of insects are also known from the formation.[6][7][8][9] which was deposited in a lacustrine environment.
Age
editDollman et al. (2018) argue that the age of the Ulan Malgait Formation is likely to be Oxfordian based on the shared presence of Shartegosuchus and Nominosuchus with the radiometrically-dated Shishigou Formation of China.[10]
See also
editReferences
edit- ^ Weishampel et al., 2004, pp.517-607
- ^ Dollman et al., 2018
- ^ Watabe, 2010
- ^ Velazco et al., 2017
- ^ Efimov et al., 2000
- ^ I. D. Sukacheva. 2000. New fossil caddis flies (Trichoptera) from the Shar-Teg locality in Mongolia. Paleontological Journal 34(Suppl 3):S347-S351
- ^ "Shar-Teg, outcrop 443/1 (PIN collection 4270)". Paleobiology Database – via fossilworks.
- ^ "Shar-Teg, outcrop 423/6 (PIN collection 4270)". Paleobiology Database – via fossilworks.
- ^ "Shar-Teg, outcrop 441/4 (PIN collection 4270)". Paleobiology Database – via fossilworks.
- ^ Bor Ukhaa hills at Fossilworks.org
Bibliography
edit- Dollman, K. N.; Clark, J. M.; Norell, M. A.; Xu, X.; Choiniere, J. M. (2018). "Convergent Evolution of a Eusuchian-Type Secondary Palate within Shartegosuchidae". American Museum Novitates (3901): 1–23. doi:10.1206/3901.1.
- Velazco, Paúl M.; Buczek, Alexandra J.; Novacek, Michael J. (2017). "Two new tritylodontids (Synapsida, Cynodontia, Mammaliamorpha) from the Upper Jurassic, southwestern Mongolia". American Museum Novitates (3874): 1–35. doi:10.1206/3874.1. hdl:2246/6698.
- Watabe, Mahito (2010). "Geology of dinosaur-fossil-bearing localities (Jurassic and Cretaceous: Mesozoic) in the Gobi Desert: Results of the HMNS-MPC Joint Paleontological Expedition". Hayashibara Museum of Natural Sciences Research Bulletin. 3. Hayashibara Museum of Natural Sciences: 41–118.
- Weishampel, David B.; Dodson, Peter; Osmólska, Halszka, eds. (2004). The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 1–880. ISBN 0-520-24209-2. Retrieved 2019-02-21.
- Efimov, M. B.; Gubin, Y. M.; Kurzanov, S. M. (2000). "New primitive crocodile (Crocodylomorpha: Shartegosuchidae) from the Jurassic of Mongolia". Paleontological Journal. 34: S238–S241.
Further reading
edit- M. Rabi, V. B. Sukhanov, V. N. Egorova, I. Danilov, and W. G. Joyce. 2014. Osteology, relationships, and ecology of Annemys (Testudines, Eucryptodira) from the Late Jurassic of Shar Teg, Mongolia, and phylogenetic definitions for Xinjiangchelyidae, Sinemydidae, and Macrobaenidae. Journal of Vertebrate Paleontology 34(2):327-352
- M. Watabe, K. Tsogtbaatar, T. Tsuihiji and R. Barsbold. 2003. The first discovery of diverse Jurassic dinosaur faunas in Mongolia. Journal of Vertebrate Paleontology 23(3, suppl.):108A
- V. B. Sukhanov. 2000. Mesozoic turtles of Middle and Central Asia. In M. J. Benton, M. A. Shishkin, D. M. Unwin, & E N. Kurichkin (eds.), The Age of Dinosaurs in Russia and Mongolia 309-367
- Y. M. Gubin and S. M. Sinitza. 1996. Shar Teg: a unique Mesozoic locality of Asia. In M. Morales (ed.), The Continental Jurassic. Museum of Northern Arizona Bulletin 60:311-318