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| Carboniferous - Monongahela formation; Conemaugh formation; Allegheny formation; Vanport limestone (1) |
| Geology -- Pennsylvania -- Armstrong County -- Maps (1) |
| Geology -- Pennsylvania -- Indiana County -- Maps (1) |
| Geology -- Pennsylvania -- Westmoreland County -- Maps (1) |
| Geology -- United States --Maps (1) |
| Neogene - Carmichaels formation (1) |