Belle Fourche Formation

The Belle Fourche Formation or Belle Fourche Shale is a fossiliferous early Late-Cretaceous geologic formation classification in Wyoming. Named for outcrops in Belle Fourche River, Wyoming, this unit name is also used in Montana, North Dakota, and South Dakota.^[1]

Belle Fourche Formation
Stratigraphic range: Cretaceous
Type	Formation
Location
Region	Montana, North Dakota, South Dakota, Wyoming
Country	United States

The unit records the gradual opening and expansion of the Greenhorn Cycle of the Western Interior Seaway, and as such is lithologically identical to the Graneros Shale Formation (that is, it is the same formation under a different name).^[2]

See also

• Earth sciences portal
• Paleontology portal

• List of fossiliferous stratigraphic units in Montana
• Paleontology in Montana
• Paleontology in North Dakota
• Paleontology in South Dakota
• Paleontology in Wyoming