Residual Aeromagnetic Map of Arizona. It may look like tie dye art, but this map displays residual magnetic intensity values are give in units of gammas. The original total field data were corrected for diurnal variation as observed at the Tucson Magnetic Observatory during the flight period.
Online resource:
Sauck, W.A. and Sumner, J.S., 1970, Residual Aeromagnetic Map of Arizona. University of Arizona Geophysical Society, 1 map sheet, map scale 1:1,000,000. http://repository.azgs.az.gov/uri_gin/azgs/dlio/1557