Upper Mississippi Valley mineral district

Region Central, North Central
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Outline of area encompassing the more than 400 known deposits within the mining district and the larger area of outlying mineralization.
Identified resources Historical production of cadmium, copper, germanium, lead, and zinc.
Production Production from 1800 to 1954 included 832,365 st metallic Pb, 1,209,965 st Zn metal, and 2,441 st Cu ore. In addition, small tonnages of barite, Fe, and iron sulfide concentrates were also produced. Small quantities of Cd and Ge were also recovered as smelter byproducts (Heyl and others, 1959).
Status Past mining.
Estimated resources Unknown.
Geologic maps Witzke and Anderson (2006), scale 1:50,000; Witzke and others (2003), scale 1:250,000; Setterholm (2014), scale 1:100,000; McGarry (2000), scale 1:62,500.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Late Cambrian sandstone; Ordovician dolomite, shale, sandstone, and limestone; Early Silurian shaley and cherty dolomite, Area cut by numerous faults and folds; ore localized along gentle folds, minor faults, joints, and unconformities.
Deposits Many small mines in mining district-most notable include Shullsburg mine (MRDS dep_id: 10080282), Raisbeck mine (MRDS dep_id: 10111349), Pint's quarry.
Evidence from mineral occurrences MRDS.
Geochemical evidence Ore bodies were at or very near the surface in the mining district. Sphalerite, galena, and barite occurrences in quarries and road cuts.
Geophysical evidence No data.
Evidence from other sources No data.
Comments The Upper Mississippi Valley district could also extend to Kane County (IL) area, which would also include parts of Sandwich Fault Zone. This makes the area of study broader and similar to a joint USGS, Illinois, Kentucky and Indiana surveys CUSMAP project conducted in the 1980s in southern Illinois. Major barite deposits are also south of the UMV district (Freiburg and others, 2017). Overlap with Mazatzal-EGRP (Eastern Granite-Rhyolite Province) suture zone. Local magnetic and gravity anomalies consistent with IOA-IOCG deposits in Missouri. overlap with Ordovician phosphate-bearing rocks.
Cover thickness and description Mining district outlined by Driftless Area of Wisconsin; some minor older glacial deposes on the fringe of the district. Loess more than 50 ft thick in placed along the banks of the Mississippi River, but generally thin elsewhere. Thicker glacial cover away from Driftless Area.
Authors Laurel G. Woodruff.
New data needs Geochemistry (Phase III); Mapping (STATE map); Geophysics (Phase III).
Geologic mapping and modeling needs Detailed geologic mapping and logging of available drill core. Construction of a 3-D model of the deposit and mafic/ultramafic intrusions would help understand district.
Geophysical survey and modeling needs High resolution aeromagnetic and aeroradiometric coverage needed, potentially over a larger area.
Digital elevation data needs Lidar variable; adequate, inadequate, and in progress.