Subject
Geology, Stratigraphic
Geology
118
Phosphate rock
42
Phosphoria Formation
25
Paleontology
18
Petrology
13
Sedimentation and deposition
8
Sandstone
7
Petroleum Geology
6
Phosphates
6
Geochemistry
5
Geology, Structural
5
Formations (Geology)
4
Mines and mineral resources
4
Texas
4
Borings
3
Cutler Formation
3
Maroon Formation (Colo.)
3
Powder River Basin (Wyo. and Mont.)
3
Reefs
3
White Rim Sandstone (Utah)
3
Alaska
2
Catastrophes (Geology)
2
Central Oklahoma Aquifer (Okla.)
2
Chinle Formation
2
Coal Geology
2
Copper ores
2
Cutler Group
2
Diagenesis
2
Extinction (Biology) History
2
Fusulinida
2
Fusulinidae
2
Geochemical prospecting
2
Groundwater
2
Guadalupe Mountains National Park (Tex.)
2
Hydrothermal alteration
2
Igneous rocks
2
Mesaverde Group
2
Metamorphic rocks
2
Micropaleontology
2
Natural gas Geology
2
Paleogeography
2
Piceance Creek Basin (Colo.)
2
Sedimentary rocks
2
Shale
2
Tethys (Paleogeography)
2
Uinta Basin (Utah and Colo.)
2
Vanadium ores
2
Yeso Formation (N.M. and Tex.)
2
Animals, Fossil
1
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