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USGS NGMDB: Cloverport quadrangle
From the National Geologic Map Database site: "Geology of the Cloverport quadrangle, Kentucky-Indiana and the Kentucky part of the Cannelton quadrangle" -
USGS Mineral Resources: Indiana geologic map data
From the site: "A GIS database of geologic units and structural features in Indiana, with lithology, age, data structure, and format written and arranged just like the other...