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Geology -- Pennsylvania -- Washington County -- Maps (3) |
Geology -- United States --Maps (3) |
Neogene - Carmichaels formation (3) |
Geology -- Pennsylvania -- Greene County -- Maps (2) |
Natural gas -- Pennsylvania -- Washington County -- Maps (2) |
Carboniferous - Greene formation; Washington formation; Monongahela formation (1) |
Carboniferous - Greene formation; Washington formation; Monongahela formation; Conemaugh formation (1) |
Carboniferous - Greene formation; Washington formation; Monongahela formation; Conemaugh formation; Ames limestone (1) |
Geology -- Pennsylvania -- Allegheny County -- Maps (1) |
Geology -- Pennsylvania -- Beaver County -- Maps (1) |