Aztec Sandstone
| Aztec Sandstone | |
|---|---|
| Stratigraphic range: Early Jurassic | |
| File:RedRocksDistortedBeds.JPG Outcrop of the Aztec Sandstone at Red Rock Canyon National Conservation Area near Las Vegas, Nevada | |
| Type | Sedimentary |
| Underlies | Willow Tank Formation[1] |
| Overlies | Chinle Formation |
| Area | Nevada,[2] Arizona, California[3] |
| Thickness | 2,100 ft (640 m) in Goodsprings quadrangle[2] 2,500 ft (760 m) in Muddy Mountain area[1] |
| Lithology | |
| Primary | sandstone |
| Other | arenite, sand |
| Location | |
| Coordinates | 35°24′N 115°30′W / 35.4°N 115.5°W |
| Approximate paleocoordinates | 20°48′N 53°24′W / 20.8°N 53.4°W |
| Region | Mojave Desert |
| Country | File:Flag of the United States (23px).png United States |
| Type section | |
| Named by | D. F. Hewett[2] |
| Year defined | 1931 |
Aztec Sandstone (the United States) Aztec Sandstone (California) | |
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The Aztec Sandstone is an Early Jurassic geological formation of primarily eolian sand from which fossil pterosaur tracks have been recovered.[4] The formation is exposed in the Mojave Desert of Arizona, California and Nevada. Aztec Sandstone is named after the Aztec Tank,[5] a lake in the Spring Mountain region of Nevada.
Description
The Aztec Sandstone is made up of two units. The lower resistant sandstone unit (100 metres (330 ft) thick) is tan to off-white in outcrops but pinkish in fresh exposures. Cross-bedded lenses can easily be observed. Frosted and pitted quartz grains well-cemented by silica are described by Evans in 1958 and 1971. The upper and less resistant unit (200m thick) consists of alternating white quartz arenites and red to brown silty sands.[6]
Vertebrate paleofauna
The formation has provided the following ichnofossils attributed to vertebrates:[4]
| Ichnofossils of the Aztec Sandstone | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Member | Abundance | Notes | Images |
| Anchisauripus[7] | Reclassified as Grallator | |||||
| Brasilichnium | ||||||
| Grallator[8] | ||||||
| Navahopus | ||||||
| Octopodichnus | ||||||
| Pteraichnus[9] | ||||||
| Skolithos | ||||||
Color key
|
Notes Uncertain or tentative taxa are in small text; |
See also
- List of fossil sites
- List of fossiliferous stratigraphic units in California
- List of fossiliferous stratigraphic units in Nevada
References
- ↑ 1.0 1.1 Longwell, C.R., No label or title -- debug: Q60182382, Wikidata Q60182382
- ↑ 2.0 2.1 2.2 Hewett, D.F., No label or title -- debug: Q61823480, Wikidata Q61823480 (incl. geologic map, scale 1:62,500)
- ↑ Jennings, C.W., 1961, Geologic map of California; Kingman sheet: California Division of Mines and Geology, scale 1:250,000
- ↑ 4.0 4.1 Aztec Sandstone at Fossilworks.org
- ↑ "Geolex — Aztec publications". ngmdb.usgs.gov. Retrieved 2023-03-14.
- ↑ Mescal Range at Fossilworks.org
- ↑ Listed as "cf. Anchisauripus" in "Appendix: Summary of the Mesozoic Reptilian Fossils of California," Hilton (2003) p. 265
- ↑ Listed as "cf. Grallator" in "Appendix: Summary of the Mesozoic Reptilian Fossils of California," in Hilton (2003) p. 265
- ↑ Lockley, et al. (2008)
Bibliography
- Bonde, J. W.; Varricchio, D. J.; Jackson, F. D.; Loope, D. B.; Shirk, A. M., E. M. Duebendorfer; E. I. Smith (eds.), No label or title -- debug: Q95597606, Wikidata Q95597606
- Lockley, M.; Harris, J.D.; and Mitchell, L. 2008. "A global overview of pterosaur ichnology: tracksite distribution in space and time." Zitteliana. B28. p. 187-198. ISSN 1612-4138.
- Porter, M.L., No label or title -- debug: Q97000543, Wikidata Q97000543
- Hilton, Richard P. 2003. Dinosaurs and Other Mesozoic Reptiles of California. Berkeley: University of California Press. 318 pp.
Further reading
- R. E. Reynolds. 1986. California trackways from the Lower Jurassic Aztec Sandstone. In D. D. Gillette (ed.), First International Symposium on Dinosaur Tracks and Traces. Abstracts with Program 24
- Geologic formations of Arizona
- Geologic formations of California
- Geologic formations of Nevada
- Jurassic Arizona
- Jurassic California
- Jurassic geology of Nevada
- Sandstone formations of the United States
- Geologic formations with imbedded sand dunes
- Aeolian deposits
- Ichnofossiliferous formations
- Paleontology in California
- Paleontology in Nevada