Region
United States
2,576
California
10
Gulf States
9
Texas
8
Colorado
6
Gulf Coast (U.S.)
6
Developing countries
5
Indian Ocean Region
5
Louisiana
5
Pennsylvania
5
West Virginia
5
Maryland
4
Mexico, Gulf of
4
San Francisco
4
Virginia
4
Arizona
3
Florida
3
Foreign countries
3
Los Angeles
3
North America
3
Afghanistan
2
Africa
2
Alabama
2
Alaska
2
Argentina
2
Baltimore
2
Burkina Faso
2
Kenya
2
Middle East
2
Mississippi
2
New York
2
New York (State)
2
Niger
2
Richmond
2
Agua Fria National Monument (Ariz.)
1
American Samoa
1
Anne Arundel County
1
Armstrong County
1
Asia, Central
1
Cambria County
1
Canada
1
Chad
1
Chicago
1
China
1
Cuba
1
Cyprus
1
Deschutes County
1
Developed countries
1
Djibouti
1
Egypt
1
more ...