Camp Rice Formation

Camp Rice Formation
Stratigraphic range: Pliocene–Pleistocene PreꞒ Ꞓ O S D C P T J K Pg N
Type	Formation
Unit of	Santa Fe Group
Overlies	Fort Hancock Formation
Thickness	88.3 ft (26.9 m)
Lithology
Primary	Sandstone
Other	Caliche
Location
Coordinates	31°19′N 105°41′W / 31.32°N 105.69°W / 31.32; -105.69
Region	Texas, New Mexico
Country	United States
Type section
Named for	Camp Rice Arroyo
Named by	W.S. Strain
Year defined	1966
Camp Rice Formation (the United States) Show map of the United States Camp Rice Formation (Texas) Show map of Texas

The Camp Rice Formation is a geologic formation in west Texas and southern New Mexico. It preserves fossils of the Pliocene-Pleistocene. These include the distinctive Tonuco Mountain Local Fauna.

Description

The formation consists of poorly cemented sandstone, conglomerate, siltstone, volcanic ash, and caliche. The color varies from pink to gray to light brown. The thickness at the type section is 88.3 ft (26.9 m), where the formation rests unconformably on the Fort Hancock Formation. The formation is capped by caliche that forms steep slopes. Where the caliche is eroded away, the underlying strata form badlands. The formation is found throughout the Hueco Basin and Mesilla Basin. Outcrops at the Tonuco Uplift northwest of Las Cruces, New Mexico, are unusually well cemented. In the southern Rio Grande rift, the formation contains numerous calcic paleosols (preserved soil layers formed in an arid climate).

The formation is interpreted as fluvial deposits following integration of the ancestral Rio Grande through the region. A piedmont facies is found in addition to the axial river facies in southern New Mexico.

Stable isotope data from the formation is consistent with a gradual warming trend in the latest Pliocene and early Pleistocene, with a generally drier climate but increased summer precipitation.

Fossils

Mammals

Name	Species	Locality	Material	Notes	Images
Camelidae	Indeterminate			A camel relative
Perrisodactyla	Indeterminate			A perissodactyl
Glyptodontinae	Indeterminate			A glyptodont
Equus	E. sp.			An equid
	E. scotti	Tonuco Mountain		A horse
	E. simplicidens			A relative of zebras and donkeys
Nannippus	N. peninsulatus			A three-toed equid
Mammuthus	M. sp.
Cuvieronius	C. sp.			A gomphothere
	C. cf. tropicus		A complete skull
Tapirus	T. sp.	Tonuco Mountain	A mandible
Leporidae	Indeterminate			A rabbit or hare
Taxidea	T. sp.			A badger
Borophagus	B. sp.			A borophagine canid
Canis	C. lepophagus			A canine canid
Rhynchotherium	R. sp.
Camelops	C. sp.			A large undescribed species
Hemiauchemia	H. sp.			A camelid
	H. blancoensis
Platygonus	P. bicalcaratus			A peccary

Reptiles

Name	Species	Locality	Material	Notes	Images
Gecholone	G. sp.			A tortoise
Kinosternon	K. sp.	Tonuco Mountain		A mud turtle
Gopherus	G. sp.			A tortoise
Hesperotestudo	H. sp.			A turtle

History

The formation was first named by W.S. Strain in 1966 for exposures near Camp Rice Arroyo in the Rio Grande valley of west Texas. J.W. Hawley and coinvestigators recommended assigning the formation to the Santa Fe Group in 1969.

Because the exposures of the formation in the Jornada del Muerto basin are relatively undisturbed by human activities, they have been used to test models of floodplain development in a tectonically active basin.

See also

• List of fossiliferous stratigraphic units in Texas
• Paleontology in Texas

Notes

References

• Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Archived from the original on 25 March 2022. Retrieved 17 December 2021.
• Hawley, J.W.; Kottlowski, Frank E.; Seager, William R.; King, William E.; Strain, William S.; LeMone, David V. (1969). "The Santa Fe Group in southcentral New Mexico border region" (PDF). New Mexico Bureau of Mines and Mineral Resources Circular. 104: 52–76. Retrieved 4 March 2021.
• Jochems, Andrew P.; Morgan, Gary S. (2018). "A stable isotope record from paleosols and groundwater carbonate of the Plio-Pleistocene Camp Rice Formation, Hatch-Rincon Basin, southern New Mexico" (PDF). New Mexico Geological Society Field Conference Series. 69: 109–117. Retrieved 4 March 2021.
• Mack, Greg H.; James, W.C. (April 1992). "Calcic paleosols of the Plio-Pleistocene Camp Rice and Palomas Formations, southern Rio Grande rift, USA". Sedimentary Geology. 77 (1–2): 89–109. Bibcode:1992SedG...77...89M. doi:10.1016/0037-0738(92)90105-Z.
• Mack, Greg H.; Madoff, Risa D. (2005-02-03). "A test of models of fluvial architecture and palaeosol development: Camp Rice Formation (Upper Pliocene-Lower Pleistocene), southern Rio Grande rift, New Mexico, USA: Plio-Pleistocene fluvial sedimentation, Rio Grande rift". Sedimentology. 52 (1): 191–211. doi:10.1111/j.1365-3091.2004.00687.x. S2CID 126626348.
• Morgan, Gary S.; Hulbert, Richard C. Jr.; Gottlieb, Eric S.; Amato, Jeffrey M.; Mack, Greg H.; Jonell, Tara N. (2017). "The tapir Tapirus (Mammalia: Perissodactyla) from the late Pliocene (early Blancan) Tonuco Mountain Local Fauna, Camp Rice Formation, Doña Ana County, southern New Mexico" (PDF). New Mexico Geology. 39 (2): 28–39. doi:10.58799/NMG-v39n2.28. Retrieved 18 March 2021.
• Seager, W.R.; Hawley, J.W.; Clemons, R.E. (1971). "Geology of San Diego Mountain area, Doña Ana County, New Mexico" (PDF). New Mexico State Bureau of Mines and Mineral Resources Bulletin. 97. Retrieved 4 March 2021.
• Strain, W.S. (1966). "Blancan mammalian fauna and Pleistocene formations, Hudspeth County, Texas". Bulletin of the Texas Memorial Museum. 10. The University of Texas at Austin. Retrieved 3 March 2021.