The formation consists mostly of red to red-brown to gray or green shale, mudstone, and arkosicsiltstone. The base of the formation is a well induratedconglomeratederived 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 (520–1,070m) 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
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
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]
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. ISBN9781585460106.
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.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
