White River Formation Stratigraphic range: Eocene-Oligocene | |
---|---|
Type | Formation |
Sub-units | Brule Formation, Chadron Formation [1] |
Overlies | Pierre Shale |
Thickness | 230–300 metres (750–980 ft) [2] |
Lithology | |
Primary | Tuffaceous claystone, conglomerate[3] |
Location | |
Region | Colorado, Nebraska, South Dakota, Wyoming |
Country | United States |
Type section | |
Named for | White River (Missouri River tributary) |
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 .
It has been found in northeastern Colorado, Dawes County in western Nebraska, Badlands of western South Dakota, and Douglas area of southeastern Wyoming.[1]
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]