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| Carboniferous - Monongahela formation; Conemaugh formation; Ames limestone; Allegheny formation; Pottsville sandstone (1) |
| Geology -- Pennsylvania -- Allegheny County -- Maps (1) |
| Geology -- Pennsylvania -- Beaver County -- Maps (1) |
| Geology -- United States --Maps (1) |
| Neogene - Carmichaels formation (1) |