formation | Command (military formation) | Elliot Formation | Lance Formation | Crato Formation | Chinle Formation | Two Medicine Formation | Tamayama Formation | Missing Man Formation (band) | Missing Man Formation | Marcellus Formation | Kirkwood Formation | Gettysburg Formation | Clarens Formation | Whitby Mudstone Formation | Tunbridge Wells Sand Formation | Santana Formation | Phalanx formation | phalanx formation | Mahantango Formation | Leduc Formation | Identity formation | Hanson Formation | Formation (stratigraphy) | formation (stratigraphy) | Formation | Centre International de Formation Européenne | Bakken formation | Yixian Formation | Vectis Formation |
The prominent red sandstone, such as Signal cliff just west of Ten Sleep, as well as the dirt hills all along the west slope of the Big Horn Mountains are of the Chugwater formation (Triassic).