White River Formation facts for kids

Quick facts for kids White River Formation Stratigraphic range: Late Eocene-Early Oligocene (Chadronian-Whitneyan) ~37.2–30.8Ma PreЄ Є O S D C P T J K Pg N
White River Badlands in South Dakota
Type	Formation
Sub-units	Brule Formation, Chadron Formation
Overlies	Pierre Shale
Thickness	230–300 m (750–980 ft)
Lithology
Primary	Tuffaceous claystone, conglomerate
Location
Coordinates	43°12′N 107°06′W / 43.2°N 107.1°W / 43.2; -107.1
Approximate paleocoordinates	44°48′N 98°24′W / 44.8°N 98.4°W / 44.8; -98.4
Region	Colorado, Nebraska, South Dakota, Wyoming
Country	United States
Extent	northern Great Plains & central Rocky Mountains
Type section
Named for	White River (Missouri River tributary)

The White River Formation is a special type of rock layer. It's like a giant stack of rocks that geologists study. This formation is found in the central Rocky Mountains and the northern Great Plains in the United States.

You can find parts of the White River Formation in several states. These include northeastern Colorado, western Nebraska (especially in Dawes County), the famous Badlands of western South Dakota, and near Douglas in southeastern Wyoming.

Amazing Ancient Animals

The White River Formation is super important because it holds many fossils. These fossils are like clues from the past. They tell us about life on Earth millions of years ago.

The fossils found here date back to the Eocene and Oligocene Epochs. These time periods were part of the Cenozoic Era. This era is sometimes called the "Age of Mammals."

Scientists have found the most complete record of vertebrate fossils from the Late Eocene and Early Oligocene in North America right here. Vertebrates are animals with backbones, like mammals, birds, and reptiles. This means we have a really good picture of the ancient animals that lived in this area.

Studying these fossils helps us understand how animals changed over time. It also shows us what the environment was like millions of years ago.