White River Formation

The White River Formation is a geologic formation of the Paleogene Period, in the northern Great Plains and central Rocky Mountains, within the United States.

White River Formation
Stratigraphic range: Late Eocene-Early Oligocene (Chadronian-Whitneyan) ~37.2–30.8 Ma PreꞒ Ꞓ O S D C P T J K Pg N
White River Badlands in South Dakota
Type	Formation
Sub-units	Brule Formation, Chadron Formation[1]
Overlies	Pierre Shale
Thickness	230–300 m (750–980 ft)[2]
Lithology
Primary	Tuffaceous claystone, conglomerate[3]
Location
Coordinates	43.2°N 107.1°W / 43.2; -107.1
Approximate paleocoordinates	44.8°N 98.4°W / 44.8; -98.4
Region	Colorado, Nebraska, South Dakota, Wyoming
Country	United States
Extent	northern Great Plains and central Rocky Mountains
Type section
Named for	White River (Missouri River tributary)
White River Formation (the United States) Show map of the United States White River Formation (Wyoming) Show map of Wyoming

It has been found in northeastern Colorado, Dawes County in western Nebraska, Badlands of western South Dakota, and Douglas area of southeastern Wyoming.^[1]

Fossil record

For the formation's prehistoric animals, see White River Fauna.

The geologic formation preserves fossils dating back to the Eocene and Oligocene Epochs of the Paleogene Period, during the Cenozoic Era.^[4] It contains the most complete Late Eocene−Priabonian and Early Oligocene−Rupelian vertebrate record in North America.^[1][5]

See also

• White River Formation prehistoric fauna
• Chadronian — Priabonian, Rupelian
• Orellan — Rupelian