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| Carboniferous - Conemaugh formation; Allegheny formation; Pottsville formation; Mauch Chunk formation (1) |
| Geology -- Pennsylvania -- Blair County -- Maps (1) |
| Geology -- Pennsylvania -- Cambria County -- Maps (1) |
| Geology -- Pennsylvania -- Clearfield County -- Maps (1) |
| Geology -- Pennsylvania -- Indiana County -- Maps (1) |
| Geology -- United States --Maps (1) |
| Neogene - unnamed strata (1) |