Ulan Malgait Formation

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Ulan Malgait Formation
Stratigraphic range: Tithonian or Oxfordian
~160–145  Ma
Type Geological formation
Sub-unitsShar Teg & Ulan Malgait Beds
Thicknessup to ~300 m (980 ft)
Lithology
Primary Mudstone
Other Sandstone, conglomerate, caliche
Location
Coordinates 44°06′N95°48′E / 44.1°N 95.8°E / 44.1; 95.8 Coordinates: 44°06′N95°48′E / 44.1°N 95.8°E / 44.1; 95.8
Approximate paleocoordinates 46°00′N98°00′E / 46.0°N 98.0°E / 46.0; 98.0
Region Govi-Altay
CountryFlag of Mongolia.svg  Mongolia
Type section
Named for Ulan Malgait Mountain
Relief map of Mongolia.png
Cyan pog.svg
Ulan Malgait Formation (Mongolia)

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 none have yet been referred to a specific genus. [1]

Contents

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

Dollman 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

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References

  1. Weishampel et al., 2004, pp.517-607
  2. Dollman et al., 2018
  3. Watabe, 2010
  4. Velazco et al., 2017
  5. Efimov et al., 2000
  6. I. D. Sukacheva. 2000. New fossil caddis flies (Trichoptera) from the Shar-Teg locality in Mongolia. Paleontological Journal34(Suppl 3):S347-S351
  7. "Shar-Teg, outcrop 443/1 (PIN collection 4270)". Paleobiology Database via fossilworks.
  8. "Shar-Teg, outcrop 423/6 (PIN collection 4270)". Paleobiology Database via fossilworks.
  9. "Shar-Teg, outcrop 441/4 (PIN collection 4270)". Paleobiology Database via fossilworks.
  10. Bor Ukhaa hills at Fossilworks.org

Bibliography

Further reading