Region
Wyoming
Green River Formation
9
Wasatch Formation
7
Sweetwater County
6
Colorado
5
Utah
5
Montana
4
Bighorn Mountains (Wyo. and Mont.)
2
Black Hills (S.D. and Wyo.)
2
Green River Watershed (Wyo.-Utah)
2
Hot Springs County
2
Rattlesnake Hills
2
Wind River Basin
2
Bighorn Basin (Mont. and Wyo.)
1
Fossil Butte National Monument
1
Fossil Butte National Monument (Wyo.)
1
Fremont County
1
Green River
1
Park County
1
Washakie Basin
1
Washakie Watershed
1
Wyoming, Central
1
Yellowstone National Park
1