Precambrian basement of the north Mid-Continent U.S.A.: a digital representation of the 1990 P.K. Sims map

Online link http://pubs.usgs.gov/of/2001/of01-021/
Description Geologic units, structural features, drill hole locations, and structure contours
Originators Dicken, Connie L.; Pimley, Shana G.; and Cannon, William F.
Publication U.S. Geological Survey Open-File Report 01-21