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Geology -- United States --Maps (2) |
Geology--Pennsylvania--Maps (2) |
Neogene - Carmichaels formation (2) |
Carboniferous - Conemaugh formation; Ames limestone; Saltsburg sandstone; Allegheny formation; Vanport limestone; Pottsville formation; Pocono formation (1) |
Carboniferous - Greene formation; Washington formation; Monongahela formation (1) |