A high sensitivity airborne radiometric and magnetic survey of the Rice Like, Iron Mountain, Eau Claire and Green Bay 1:250,000 NMTS Quadrangles within the states of Wisconsin, Michigan, and Minnesota. A total of 10,340 line miles of high sensitivity radiometric and magnetic data were collected within these quadrangles. Traverse lines were flown at a spacing of 3.125 miles in an east/west direction at a 18.375 miles seperation. All data were collected utilizing a fixed wing aircraft and over 3,500 cubic inches of Nal crystal detector. Magnetometer data were collected utilizing a high sensitivity proton magnetometer. Data were recorded digitally at 1.0 second intervals aboard the aircraft. Navigation was performed using both visual and doppler techniques. All data presented in this report as corrected profiles of all radiometric variables, magnetic data, radar and barometric altimeter data, air temperature and airborne bismuth contributions. Radiometric data presented are corrected for Comptron Scatter, altitude dependence and atmospheric Bismuth. These data are also presented on microfiche, and digital magnetic tapes. In addition, anomaly maps and inerpretation maps are presented in relating known geology or soil distribution to the corrected radiometric magnetic data.