1. Maps showing thickness and limestone-dolostone ratios of selected Paleozoic carbonate units in the northern midcontinent, U.S.A Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by U.S. Geological Survey Information Services Resource Type: Map Access & Availability: Loading
2. Maps showing areal extent of selected Paleozoic shales in the northern midcontinent, U.S.A Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by Map Distribution Resource Type: Map Access & Availability: Loading
3. Map showing distribution of alkaline igneous rocks and associated carbonatites and peridotites in the northern midcontinent, U.S.A Author/Creator: Geological Survey (U.S.) Publication/Creation: Reston, Va. : U.S. Geological Survey, 1991 Resource Type: Map Access & Availability: Loading
4. Lithologic cross sections of phanerozoic rocks in the northern midcontinent, U.S.A Author/Creator: Geological Survey (U.S.) Publication/Creation: Reston, Va. : U.S. Geological Survey, 1991 Resource Type: Map Access & Availability: Loading