Summary
The Crevasse Canyon Formation is a coal-bearing Cretaceous geologic formation in New Mexico and Arizona.
| Crevasse Canyon Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Formation |
| Unit of | Mesaverde Group |
| Sub-units | Dilco Coal, Dalton Sandstone & Gibson Coal Members |
| Underlies | Point Lookout Sandstone |
| Overlies | Gallup Sandstone |
| Thickness | 700 ft (210 m) |
| Lithology | |
| Primary | Sandstone, mudstone, coal |
| Location | |
| Coordinates | 35°47′30″N 108°56′41″W / 35.7916°N 108.9446°W |
| Region | New Mexico, Arizona |
| Country |  United States |
| Extent | San Juan Basin |
| Type section | |
| Named for | Crevasse Canyon |
| Named by | Allen and Balk |
| Year defined | 1954[1] |
  Crevasse Canyon Formation (the United States)  Crevasse Canyon Formation (New Mexico) | |
Description edit
The formation is divided into three members, in ascending stratigraphic order: Dilco Coal Member, Dalton Sandstone Member, and Gibson Coal Member. The Dilco Coal Member is described by Cather (2010) as "Drab mudstone, fine- to medium-grained sandstone, and coal. Sandstone is commonly crossbedded or ripple laminated." The Dalton Sandstone Member is described as "Gray to yellowish gray, fine- to medium-grained, cliff-forming sandstone." The Gibson Coal Member is described as "Drab mudstone, buff, brown, and greenish gray sandstone (commonly cross-bedded), and coal," with the coals typically less than 0.5 m thick.[2] Thickness is 700 feet (210 m) at the type section.[1]
In some exposures, the Dilco Coal Member is separated from the Dalton Sandstone Member by the Mulatto Tongue of the Mancos Shale.[3] A fourth member of the Crevasse Canyon Formation, the Borrego Pass Lentil, is found in a limited exposure area between the Dilco Coal Member and the Mulatto Tongue. The Borrego Pass Lentil is a highly variable sandstone.[4]
In southern New Mexico, the Crevasse Canyon Formation contains fossil soils (paleosols) typical of a humid climate (alfisol and inceptisols). The underlying Mojado Formation contains paleosols typical of an arid climate (aridisols), suggesting a shift from an arid to a humid climate across the lower Cretaceous - upper Cretaceous boundary in this region.[5]
Fossil content edit
Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.[6] The formation is the type formation for Neurankylus notos, a baenid turtle that is the earliest representative of its genus.[7] Two dinosaur fossil trackways have been identified in the formation near Elephant Butte Reservoir.[8]
Petrified wood is common in the Gibson Coal Member.[2][9]
Age edit
Tschudy (1976) identified the Crevasse Canyon formation as Coniacian and Santonian by palynology of coal and shale.[10]
Economic resources edit
In the San Juan Basin, the Gibson Coal Member and the Dilco Coal Member were exploited for coal for steam locomotives from the 1940s to the 1990s. However, they constitute less than 1% of the original coal reserves of San Juan Basin.[11]
History of investigation edit
The formation was originally described in 1954 by Allen and Balk as part of the Mesaverde Group.[1]
See also edit
References edit
- ^ a b c Allen & Balk 1954.
- ^ a b Cather 2010.
- ^ O'Sullivan et al. 1972.
- ^ Correa 1970.
- ^ Mack, Greg H. (1992). "Paleosols as an Indicator of Climatic Change at the Early-Late Cretaceous Boundary, Southwestern New Mexico". SEPM Journal of Sedimentary Research. 62. doi:10.1306/D426792E-2B26-11D7-8648000102C1865D.
- ^ Weishampel, Dodson & Osmólska 2004, pp. 517–607.
- ^ Lichtig & Lucas 2016.
- ^ Lucas, Spencer G.; Dalman, Sebastian G.; Sullivan, Robert M. (2016). "Cretaceous dinosaur footprints from Sierra County, New Mexico". New Mexico Museum of Natural History and Science Bulletin. 74: 151–152. Retrieved 1 September 2021.
- ^ Estrada-Ruiz et al. 2012.
- ^ Tschudy 1976.
- ^ Fassett 1989.
Bibliography edit
- Allen, J.E.; Balk, Robert (1954). "Mineral Resources of Fort Defiance and Tohatchi quadrangles, Arizona and New Mexico" (PDF). New Mexico Bureau of Mines and Mineral Resources Bulletin. 36. Retrieved 11 September 2020.
- Cather, Steven (2010). "Preliminary geologic map of the San Lucas Dam quadrangle, McKinley County, New Mexico". New Mexico Bureau of Geology and Mineral Resources, Open-File Geologic Map. OF-GM 212. Retrieved 11 September 2020.
- Correa, A.C. (1970). "Borrego Pass Lentil, a new member of the Crevasse Canyon Formation, southern San Juan basin, New Mexico". The Mountain Geologist. 7 (2): 99–102. Retrieved 31 August 2021.
- Estrada-Ruiz, Emilio; Upchurch, Garland R.; Wheeler, Elisabeth A.; Mack, Greg H. (May 2012). "Late Cretaceous Angiosperm Woods from the Crevasse Canyon and McRae Formations, South-Central New Mexico, USA: Part 1". International Journal of Plant Sciences. 173 (4): 412–428. doi:10.1086/664714. S2CID 83998771.
- Fassett, James E. (1989). "Coal resources of the San Juan Basin" (PDF). New Mexico Geological Society Field Conference Series. 40: 303–307. Retrieved 1 September 2021.
- Lichtig, Asher J.; Lucas, Spencer G. (2016). "A new species of Neurankylus (Testudines; Baenidae) from the upper Cretaceous Crevasse Canyon Formation, Southern New Mexico, USA". New Mexico Museum of Natural History and Science Bulletin. 74: 117–119. Retrieved 31 August 2021.
- O'Sullivan, R.B.; Repenning, C.A.; Beaumont, E.C.; Page, H.G. (1972). "Stratigraphy of the Cretaceous rocks and the Tertiary Ojo Alamo Sandstone, Navajo and Hopi Indian Reservations, Arizona, New Mexico, and Utah". U.S. Geological Survey Professional Paper. Professional Paper. 521-E: E1–E65. doi:10.3133/pp521E.
- Tschudy, R.H. (1976). "Palynology of Crevasse Canyon and Menefee Formation of San Juan basin, New Mexico" (PDF). New Mexico Bureau of Mines and Mineral Resources Circular. 154: 48–55. Retrieved 11 September 2020.
- Weishampel, David B.; Dodson, Peter; Osmólska, Halszka, eds. (2004). The dinosauria (2nd ed.). Berkeley, Calif.: University of California Press. ISBN 0-520-24209-2.