The Alagteeg Formation is a geological formation in Mongolia whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.[1] It predominantly consists of alternating reddish brown mudstone and horizontally laminated sandstone, with ripple cross laminations and rhizoliths. It was first formally defined as a unit by Hasegawa et al. in 2008 as a distinct unit from the overlying Djadochta Formation. The environment of deposition is suggested to be fluvial, originating in sandy braided river, floodplain and ephemeral lake depositional environments, as opposed to the desert depositional environment of the Djadochta Formation.[2]

Alagteeg Formation
Stratigraphic range: Santonian-Campanian
~85–72 Ma
TypeGeological formation
UnderliesDjadochta Formation
Thickness~16 m (52 ft) at the Bayan Zag locality
Lithology
PrimarySandstone, mudstone
Location
Coordinates44°18′N 103°18′E / 44.3°N 103.3°E / 44.3; 103.3
Approximate paleocoordinates41°54′N 92°24′E / 41.9°N 92.4°E / 41.9; 92.4
RegionÖmnögovi Province
Country Mongolia
ExtentUlaan Nuur Basin
Type section
Named forAlag Teeg
Named byHasegawa et al.
Year defined2009
Thickness at type section~15 m (49 ft)
Alagteeg Formation is located in Mongolia
Alagteeg Formation
Alagteeg Formation (Mongolia)

Fossil content

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Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs

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Sauropoda

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Sauropods of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images
Abdarainurus[3] A. barsboldi A titanosaurian sauropod  

Theropods

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Theropods of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Ornithopods

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Ornithopods of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images
Pinacosaurus[1] P. grangeri A ankylosaurid thyreophoran
Plesiohadros P. djadokhtaensis A hadrosauroid ornithopod
Protoceratops[1] P. andrewsi A protoceratopsid ceratopsian

Pterosaurs

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Pterosaurs of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Crocodylomorphs

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Crocodylomorphs of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Squamates

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Squamates of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Turtles

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Turtles of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images
Trionychidae Indet. Indeterminate

Amphibians

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Amphibians of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Fish

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Fishes of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

Mammals

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Mammals of the Alagteeg Formation
Genus Species Location Stratigraphic position Material Notes Images

See also

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References

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  1. ^ a b c Weishampel et al., 2004, pp.593-600
  2. ^ Hasegawa et al., 2009
  3. ^ Alexander O. Averianov; Alexey V. Lopatin (2020). "An unusual new sauropod dinosaur from the Late Cretaceous of Mongolia". Journal of Systematic Palaeontology. 18 (12): 1009–1032. Bibcode:2020JSPal..18.1009A. doi:10.1080/14772019.2020.1716402. S2CID 214244529.

Bibliography

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