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Maps

Our programs produce accurate geologic maps and 3-D geologic frameworks that provide critical data for sustaining and improving the quality of life and economic vitality of the Nation. They also organize, maintain, and publish the geospatial baseline of the Nation's topography, natural landscape, built environment and more.

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Filter Total Items: 9477

Geologic map of the Triangle A pegmatite, Custer County, South Dakota

The Triangle A pegmatite is 4 miles southeast of Custer in the SW 1/4, sec. 34, T. 3 S., R. 5 E., Custer County, S. Dak.  It may be reached from Custer by a gravel road 2.4 miles long that leaves U.S. Highway 16A at a point 3.2 miles east of Custer.

Geology and zinc-lead deposits in the Couler Valley area, Dubuque County, Iowa

Geologic investigations were begun in the Iowa portion of the Wisconsin-Illinois-Iowa zinc-lead district to appraise its potentialities: (1) for zinc ore in strata that elsewhere in the mining district contain large zinc ore bodies and (2) for lead and zinc deposits of the type that were mined extensively in Dubuque County, Iowa, during the 19th century.

Geology and zinc-lead deposits in the Durango area, Dubuque County, Iowa

Geologic investigations were begun in Iowa to appraise; (1) the possible occurrence of zinc ore in strata that elsewhere in the Upper Mississippi Valley zinc-lead district have been the principal sites of zinc concentration; and (2) lead ore of the type known as "crevice deposits," which were mined so extensively during the 19th century in Dubuque County, Iowa, but have been mined very little sinc