The Hidalgo Formation is a geologic formation of Maastrichtian age (latest Cretaceous)[1] in southwestern New Mexico.[2] It is of interest to geologists for the clues it preserves of the nature of Laramide deformation in the latest Cretaceous.[3]

Hidalgo Formation
Stratigraphic range: Maastrichtian
~70.53–71.44 Ma
TypeGeological formation
UnderliesRubio Peak Formation
OverliesRingbone Formation, Skunk Ranch Formation
Thickness7,500 feet (2,300 m)
Lithology
PrimaryBasalt, andesite
OtherVolcaniclastics, limestone, shale
Location
Coordinates31°50′49″N 108°27′25″W / 31.847°N 108.457°W / 31.847; -108.457
RegionNew Mexico
Country United States
Type section
Named forHidalgo County, New Mexico
Named byS.G. Lasky
Year defined1938
Hidalgo Formation is located in the United States
Hidalgo Formation
Hidalgo Formation (the United States)
Hidalgo Formation is located in New Mexico
Hidalgo Formation
Hidalgo Formation (New Mexico)

Description edit

The formation is mostly basalt[4] or andesite[5] lava flows, but with some interbedded breccia and pyroclastic rock and, in some locations, up to 200 feet (61 m) of limestone and shale. The formation rests unconformably on the Ringbone Formation[4] or Skunk Ranch Formation,[6] and varies greatly in thickness, from 900 to 5,000 feet (270 to 1,520 m).[4] Argon-argon dating gives a consistent age between 70.53 and 71.44 million years.[7] The formation is overlain by the Rubio Peak Formation.[6]

The formation is interpreted as a volcanic center located inland of the southwest coast of the Ringbone depositional basin[4] that erupted during Laramide tectonic deformation that partitioned the basin.[8] It may correlate with the Salero Formation of southeastern Arizona.[9]

History of investigation edit

The formation was first named the Hidalgo Volcanics by Samuel G. Lasky in 1978 for outcroups found throughout Hidalgo County, New Mexico.[4]

References edit

  1. ^ Marvin, R.F.; Naeser, C.W.; Mehnert, H.H. (1978). "Tabulation of radiometric ages--Including unpublished K-Ar and fission-track ages for rocks in southeastern Arizona and southwestern New Mexico" (PDF). New Mexico Geological Society Field Conference Series. 29: 243–252. Retrieved 14 October 2021.
  2. ^ Lasky, Samuel G. (1938). "Newly Discovered Section of Trinity Age in Southwestern New Mexico". AAPG Bulletin. 22 (5): 524–540. doi:10.1306/3D932F80-16B1-11D7-8645000102C1865D. ISSN 0149-1423.
  3. ^ Jennings, George R.; Lawton, Timothy F.; Clinkscales, Christopher A. (June 2013). "Late Cretaceous U–Pb tuff ages from the Skunk Ranch Formation and their implications for age of Laramide deformation, Little Hatchet Mountains, southwestern New Mexico, U.S.A.". Cretaceous Research. 43: 18–25. Bibcode:2013CrRes..43...18J. doi:10.1016/j.cretres.2013.02.001.
  4. ^ a b c d e Lasky 1938.
  5. ^ Zeller, R.A. Jr. (1970). "Geology of the Little Hatchet Mountains, Hidalgo and Grant Counties, New Mexico" (PDF). New Mexico Bureau of Mines and Mineral Resources Bulletin. 96. Retrieved 16 September 2020.
  6. ^ a b Jennings, Lawton & Clinkscales 2013.
  7. ^ Young, John R.; McMillan, Nancy J.; Lawton, Timothy F.; Esser, Richard P. (2000). "Volcanology, geochemistry and structural geology of the Upper Cretaceous Hidalgo Formation, southwestern New Mexico" (PDF). New Mexico Geological Society Field Conference Series. 51: 149–156. Retrieved 14 October 2021.
  8. ^ Basabilbazo, George (2000). "The Upper Cretaceous Ringbone Formation, Little Hatchet Mountains, southwestern New Mexico" (PDF). New Mexico Geological Society Field Conference Series. 51: 203–210. Retrieved 14 October 2021.
  9. ^ * Hayes, Philip Thayer (1970). "Cretaceous paleogeography of southeastern Arizona and adjacent areas". U.S. Geological Survey Professional Paper. Professional Paper. 658-B. doi:10.3133/pp658B.