Hell-to-Finish Formation
Hell-to-Finish Formation | |
---|---|
Stratigraphic range: | |
Type | Formation |
Unit of | Bisbee Group |
Underlies | U-Bar Formation |
Overlies | Various Paleozoic units, Broken Jug Formation |
Thickness | 1,700–3,500 feet (520–1,070 m) |
Lithology | |
Primary | Shale, mudstone, siltstone |
Location | |
Coordinates | 31°32′36″N 108°20′28″W / 31.5433°N 108.3411°W |
Region | New Mexico |
Country | United States |
Type section | |
Named for | Hell-to-Finish tank |
Named by | R.A. Zeller Jr. |
Year defined | 1965 |
The Hell-to-Finish Formation is a geologic formation in southwestern New Mexico. It preserves fossils dating back to the early Cretaceous period.[1][2][3]
Description
[edit]The formation consists mostly of red to red-brown to gray or green shale, mudstone, and arkosic siltstone. The base of the formation is a well indurated conglomerate derived from the underlying Paleozoic beds. Minor arkose and limestone are present in the uppermost beds.[1] The total thickness is up to 1,700–3,500 feet (520–1,070 m) but varies considerably over the region. The formation rests on a profound unconformity with underlying Paleozoic formations in most locations, but overlies the Broken Jug Formation in the Little Hatchet Mountains.[4] The Hell-to-Finish Formation is transitional to the overlying U-Bar Formation.[3] The transitional contact with the Aptian U-Bar Formation suggests that the Hell-to-Finish Formation cannot be much older than Aptian.[5]
The formation is interpreted as being deposited in an arid client, based on the nature of paleosols within the formation.[6] Deposition took place in a west-northwest-trending rift basin.[7]
Fossils
[edit]The upper beds of the formation contain abundant pelecypods.[1] However, no age-diagnostic fossils have been found in the formation.[5]
History of investigation
[edit]The formation was first defined by Zeller in 1965 for exposures near the Hell-to-Finish tank in the southern Big Hatchet Mountains of New Mexico.[1]
See also
[edit]Footnotes
[edit]- ^ a b c d Zeller 1965.
- ^ Hayes 1970.
- ^ a b Lawton 2004, pp. 159–161.
- ^ Lucas et al. 2001.
- ^ a b Lucas & Estep 1998.
- ^ Mack 1992.
- ^ Mack 1987.
References
[edit]- Hayes, P.T. (1970). "Cretaceous paleogeography of southeastern Arizona and adjacent areas". U.S. Geological Survey Professional Paper. 658-B: B1 – B42. Retrieved 5 August 2020.
- Lawton, Timothy F. (2004). "Upper Jurassic and lower Cretaceous strata of southwestern New Mexico and northern Chihuahua, Mexico". In Mack, G.H.; Giles, K.A. (eds.). The geology of New Mexico. A geologic history: New Mexico Geological Society Special Volume 11. pp. 153–168. ISBN 9781585460106.
- Lucas, Spencer G.; Estep, John W. (1998). "Lithostratigraphy and biostratigraphy of the lower-middle Cretaceous Bisbee Group, southwestern New Mexico, USA". New Mexico Museum of Natural History and Science Bulletin. 14: 39–55. Retrieved 16 September 2020.
- Lucas, Spencer G.; Zeigler, Kate E.; Lawton, Timothy; Filkorn, Harry (February 2001). "Late Jurassic invertebrate fossils from the Little Hatchet Mountains, southwestern New Mexico". New Mexico Geology. 23: 16–20. doi:10.58799/NMG-v23n1.16. Retrieved 16 September 2020.
- Mack, Greg H. (1 May 1987). "Mid-Cretaceous (late Albian) change from rift to retroarc foreland basin in southwestern New Mexico". GSA Bulletin. 98 (5): 507–514. Bibcode:1987GSAB...98..507M. doi:10.1130/0016-7606(1987)98<507:MLACFR>2.0.CO;2.
- 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.
- Zeller, R.A. Jr. (1965). "Stratigraphy of the Big Hatchet Mountains area, New Mexico" (PDF). New Mexico Bureau of Mines and Mineral Resources Memoir. 16. Retrieved 15 September 2020.