Spatial Coverage
- Nebraska6
- Salt Lake County6
- Tucson Region6
- United States6
- Chester County5
- Iowa5
- Long Island5
- North Carolina5
- Pima County5
- Virginia5
- Alachua County (Fla.)4
- Aquia Formation4
- California, Southern4
- Colorado River Watershed (Colo.-Mexico)4
- High Plains (U.S.)4
- Iowa.4
- Massachusetts4
- Mississippi River Valley4
- North Dakota4
- Palm Beach County4
