Aeromagnetic Map of Nebraska (GP-4): Burchett, R. R. (1:1,000,000; 1985), size 33" x 17". Description: Contour interval is 100 gammas. Hachured to indicate closed areas of lower magnetics. Map based on aeromagnetic measurements made during 1976 to 1981 by various subcontractors for the U.S. Department of Energy (DOE) as part of the National Uranium Resource Evaluation (NURE) program. Relative total intensity was converted from absolute total intensity by subtracting the International Geomagnetic Reference Field (1975).