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The Map Collection is the regional depository for all maps issued by the United States Federal Depository Program, which includes many USGS maps, Open File Reports (OFRs), and Miscellaneous Investigations Series Maps (MIS). The Collection has excellent geologic coverage of Washington state, very good coverage of the rest of the United States, and good coverage for most of the world.
Use UW Libraries Search to find geologic maps.
Digital geologic maps
Geologic maps represent the physical forces which act upon the Earth, the chemistry of the materials of which the Earth is made, the shape of the surface of the Earth, and the biology of the past as evidenced by fossils.
(Adapted from the definition of "geology," Glossary of the Mapping Sciences, p. 219, Suzzallo Ground Floor Reference TA505.G57 1994.)