1. Structure map of Archean rocks, Palmer and Sands 7 1/2-minute quadrangles, Michigan, showing Great Lakes tectonic zone Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by Map Distribution Resource Type: Map Access & Availability: Loading
2. Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan Author/Creator: Geological Survey (U.S.) Publication/Creation: Reston, Va. : U.S. Geological Survey, 1992 Resource Type: Map Access & Availability: Loading
3. Precambrian basement map of the Trans-Hudson orogen and adjacent terranes, northern Great Plains, U.S.A Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by U.S. Geological Survey Map Distribution Resource Type: Map Access & Availability: Loading