The Nugget Sandstone is a Late Triassic to Early Jurassic geologic formation that outcrops in Colorado, Idaho, Wyoming, and Utah, western United States.

Nugget Sandstone
Stratigraphic range: Norian-Toarcian
~220–180 Ma
Salmon-pink and white sandstones of the upper part of the Nugget Formation, Wind River Mountains, Wyoming
TypeGeological formation
Unit ofGlen Canyon Group
UnderliesCarmel Formation
OverliesChinle Formation
Thickness200 m (660 ft)
Lithology
PrimarySandstone
OtherMudstone, siltstone
Location
Coordinates40°24′N 109°18′W / 40.4°N 109.3°W / 40.4; -109.3
Approximate paleocoordinates27°24′N 46°36′W / 27.4°N 46.6°W / 27.4; -46.6
RegionColorado, Idaho, Utah
Country United States
ExtentColorado Plateau
Nugget Sandstone is located in the United States
Nugget Sandstone
Nugget Sandstone (the United States)
Nugget Sandstone is located in Utah
Nugget Sandstone
Nugget Sandstone (Utah)
Nugget Sandstone near Red Fleet Reservoir, Uintah County, Utah. Uniform grain size and these large cross-stratification are indicative of an ancient sand dune.
Nugget Sandstone showing a bounding surface between two sets of ancient sand dunes, where wind scour eroded the top of the lower dune before the second dune advanced over it. Red Fleet Reservoir, Uintah County, Utah.
Eubrontes track in the Nugget Sandstone, Red Fleet State Park, Uintah County, Utah.

In Wyoming, it is composed of a lower hematite-stained siltstone and thin-bedded sandstone. The upper part is a salmon-pink and light-gray, fine- to medium-grained cliff-forming sandstone that exhibits massive bedding to large scale cross-beds of dunes. Thickness ranges up to 86.9 m (285 feet).[1]

Fossil theropod tracks have been reported from the formation.[2]

Fossil content

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Intermediate theropod, sphenosuchian, drepanosaurid and sphenodontian remains are known.[3]

Paleofauna reported from the Nugget Sandstone
Genus Species Material Notes Images
Caelestiventus[4] C. hanseni Most of the skull, a complete lower jaw, a finger bone A dimorphodontid pterosaur, the first known diagnostic pterosaur in North America.
Other fossils

Ichnofossils

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See also

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References

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  1. ^ Johnson, J.F. and Sutherland, W.M., 2009, Geologic map of the Lander 30' x 60' quadrangle, Fremont County, Wyoming, Wyoming State Geological Survey, Map Series MS-87, 1:100,000.
  2. ^ Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607.
  3. ^ B. B. Britt, D. J. Chure, G. F. Engelmann and J. D. Shumway. 2016. Rise of the erg—paleontology and paleoenvironments of the Triassic-Jurassic transition in northeastern Utah. Geology of the Intermountain West 3:1-32
  4. ^ Brooks B. Britt; Fabio M. Dalla Vecchia; Daniel J. Chure; George F. Engelmann; Michael F. Whiting; Rodney D. Scheetz (2018). "Caelestiventus hanseni gen. et sp. nov. extends the desert-dwelling pterosaur record back 65 million years". Nature Ecology & Evolution. 2 (9): 1386–1392. Bibcode:2018NatEE...2.1386B. doi:10.1038/s41559-018-0627-y. PMID 30104753. S2CID 51984440.

Bibliography

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  • Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. ISBN 0-520-24209-2

Further reading

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