Geography
United States
2,403 results
Mexico
102 results
United States Virgin Islands
44 results
Texas
42 results
Arizona
41 results
Sonora (Mexico : State)
38 results
Sonora (State)
38 results
Mexican-American Border Region
36 results
California
34 results
Puerto Rico
28 results
New Mexico
24 results
Canada
23 results
Colorado
22 results
Alaska
20 results
Wyoming
20 results
Tamaulipas (Mexico : State)
19 results
Tamaulipas (State)
19 results
Atlantic Coast (U.S.)
17 results
Baja California (Mexico : State)
17 results
Baja California (State)
17 results
Chihuahua (Mexico : State)
17 results
Chihuahua (State)
17 results
Hawaii
15 results
Green River Formation
11 results
Gulf Coast
11 results
Gulf Coast (U.S.)
11 results
West (U.S.)
11 results
Antarctica
10 results
Appalachian Basin
10 results
Florida
9 results
Floridan Aquifer
9 results
Kansas
8 results
Maryland, Southern
8 results
Mexico, Gulf of
8 results
Mississippi River Valley
8 results
Montana
8 results
Uinta Basin
8 results
Uinta Basin (Utah and Colo.)
8 results
High Plains
7 results
High Plains Aquifer
7 results
Mississippi River
7 results
Nevada
7 results
Wasatch Formation
7 results
Black Hills (S.D. and Wyo.)
6 results
Coahuila (Mexico : State)
6 results
Coahuila (State)
6 results
High Plains (U.S.)
6 results
Maryland
6 results
Southern Maryland
6 results
Utah
6 results
more…