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Geology -- United States --Maps (5) |
Geology--Illinois--Maps (5) |
Neogene - unnamed strata (2) |
Carboniferous - McLeansboro formation; Carbondale formation (1) |
Carboniferous - McLeansboro formation; Carbondale formation; Pottsville sandstone; Birdsville formation (1) |
Geology--Iowa--Maps (1) |