Narrower Terms (18)

• Alcova Limestone (Wyo.)
• Chinle Formation
• Chugwater Group (Wyo.)
• Dockum Formation
• Dockum Group
• Dubrajpur Formation (India)
• Etivluk Group (Alaska)
• Gassum Formation (Denmark)
• Koipato Formation (Nev.)
• Kutcho Formation (B.C.)
• Navajo Sandstone
• Santa Rosa Formation (N.M. and Tex.)
• Skagerrak Formation
• Takla Group (B.C.)
• Tonga Formation (B.C. and Wash.)
• Union Wash Formation (Calif.)
• Xujiahe Formation (China)
• Yanchang Formation (China)