AFMAG; applications and limitations

The repeatability of AFMAG measurements has ranged from good to bad since the introduction of the method to industry in 1958. In some applications, e.g., mapping massive sulfide “dikes,” the repeatability is generally good, while in other applications, e.g., mapping broad fault zones, the repeatability is notoriously poor. In an endeavor to elucidate the factors controlling repeatability of AFMAG dip angle readings, we have conducted a continuing program of research in the State of California since 1961.