Aeromagnetic Anomalies Midcontinent Rift System
Regional aeromagnetic anomalies over the Midcontinent Rift System region. White dots show locations of known Keweenawan nickel-copper-platinum group element (Ni-Cu-PGE) mineral deposits. Gray block pattern shows area of Phanerozoic sedimentary cover. Red polygon shows location of northeast Iowa Intrusive Complex (NE IIC).