Subject
Arizona
Geology
37
Geology, Stratigraphic
17
Mines and mineral resources
6
Ore deposits
6
Nevada
5
Groundwater
3
Petrology
3
Uranium ores
3
Evapotranspiration
2
Geochemical prospecting
2
Manganese ores
2
California
1
Channels (Hydraulic engineering)
1
Copper Assaying
1
Copper mines and mining
1
Copper ores
1
Desert plants
1
Evapotranspiration Measurement
1
Floods
1
Forest meteorology
1
Forests and forestry
1
Gold ores
1
Hydrology
1
Igneous rocks
1
Limestone
1
Mule Mountains (Ariz.)
1
Paleogeography
1
Plant ecology
1
Quartzite
1
Rain and rainfall
1
Salt deposits
1
Sedimentary rocks
1
Sediments (Geology)
1
Serpentine
1
Silicate minerals
1
Utah
1
Vanadium ores
1
Volcanic ash, tuff, etc
1
Water-supply
1
Zeolites
1