Region
Alaska
1
Arizona
1
Big Horn County
1
Big Horn County (Mont.)
1
Bighorn Mountains (Wyo. and Mont.)
1
California
1
Campbell County
24
Campbell County (Wyo.)
15
Carbon County
3
Colorado
2
Converse County
1
Converse County (Wyo.)
1
Fort Union Formation
2
Fremont County
4
Gillette
1
Gillette Coal Field
1
Gillette Region
1
Green River Formation
1
Green River Watershed (Wyo.-Utah)
1
Hanna Basin
1
Hawaii
1
Idaho
2
Johnson County
13
Johnson County (Wyo.)
10
Lincoln County
2
Minnesota
1
Montana
8
Natrona County
1
North America
1
North Dakota
1
Norton Bay-Nulato region
1
Pennsylvania
1
Point of Rocks quadrangle
1
Powder River Basin (Wyo. and Mont.)
3
Powder River County
7
Powder River County (Mont.)
7
Powder River Watershed (Wyo. and Mont.)
1
Red Desert
1
Red Desert Region
2
Saddle Horse Butte Quadrangle
1
San Bernardino County
1
Seward Peninsula
1
Sheridan County
17
Sheridan County (Wyo.)
7
Sweetwater County
9
Sweetwater County (Wyo.)
1
Texas
1
Truman Draw Quadrangle
1
United States
1
Utah
1
more ...