Barstow Formation

Barstow Formation
Stratigraphic range: Early to Middle Miocene (Barstovian)
~19.3–13.4 Ma
Barstow Formation exposed in Owl Canyon near Barstow, California.
TypeSedimentary
Lithology
Primarylimestone, shale, siltstone, sandstone, tuff
Otherconglomerate
Location
RegionMojave Desert,
California
CountryUnited States
ExtentNorthern San Bernardino County, Southeastern California
Type section
Named forBarstow, California
Named byHershey (1902)

The Barstow Formation is a series of limestones, conglomerates, sandstones, siltstones and shales exposed in the Mojave Desert near Barstow in San Bernardino County, California.[1][2]

It is of the early to middle Miocene epoch, (19.3 - 13.4 million years ago) in age, in the Neogene Period.[3] It lends its name to the Barstovian North American land mammal age (NALMA).

The sediments are fluvial and lacustrine in origin except for nine layers of rhyolitic tuff.[3] It is well known for its abundant vertebrate fossils including bones, teeth and footprints.[4] The formation is also renowned for the fossiliferous concretions in its upper member, which contain three-dimensionally preserved arthropods.

  1. ^ Dibblee, T.W., Jr. (1967). Areal Geology of the Western Mojave Desert, California. Geological Survey Professional Paper no. 522. United States Government Printing Office, Washington D.C.
  2. ^ Dibblee, T.W., Jr. (1968). Geology of the Fremont Peak and Opal Mountain Quadrangles, California. California Division of Mines and Geology, San Francisco.
  3. ^ a b Woodburne, M.O., Tedford, R.H., Swisher III, C.C. (1990). Lithostratigraphy, biostratigraphy, and geochronology of the Barstow Formation, Mojave Desert, southern California: Geological Society of America Bulletin, Vol. 102, p. 459-477.
  4. ^ Lindsay, E.H. (1972). Small Mammal Fossils from the Barstow Formation, California. University of California Publications in Geological Sciences, Vol. 93. University of California Press, Berkeley.