Basis for focus area |
Geophysical expression indicates a very large volume of mafic/ultramafic rocks; geophysical expression is also consistent with large volume of alkaline rocks, including carbonatites and large alkaline complexes. |
Identified resources |
Unknown. |
Production |
Unknown. |
Status |
Limited past exploration (4 boreholes). |
Estimated resources |
No data. |
Geologic maps |
Jirsa and others (2012), scale 1:500,000. |
Geophysical data |
Adequate aeromagnetic coverage for southern half, inadequate for northern half; inadequate aeroradiometric coverage. |
Favorable rocks and structures |
Large volumes of mafic/ultramafic intrusive rocks, significant portion of these may be alkaline complexes, including perhaps carbonatites. Located at the intersection of two major crustal-scale (lithospheric-scale?) fault zones: the Belle Plaine and Fayette structural zones. Possible rock type and presence of major structural zone permissive for occurrence of critical minerals, although none are known. |
Deposits |
No data. |
Evidence from mineral occurrences |
No data. |
Geochemical evidence |
No data. |
Geophysical evidence |
Gravity highs and complex magnetic anomalies. |
Evidence from other sources |
No data. |
Cover thickness and description |
Covered by 200-700 m of Paleozoic sedimentary cover. |
Authors |
Benjamin J. Drenth. |
New data needs |
New mapping, high resolution geophysics. |
Geologic mapping and modeling needs |
Basement geologic map needed. |
Geophysical survey and modeling needs |
Need Rank 1 aeromagnetic data and more ground gravity data over the northern half of focus area. |
Digital elevation data needs |
Lidar in progress or planned for the area, but not needed (concealed). |