Discussion on: "Magnetic susceptibility mapping at Broken Hill, Australia" by B.P.J. Stevens, Exploration Geophysics 30 (1999), 105?112

Abstract

Mr Stevens indicated that he had used a Geo Instruments' Magnetic Susceptibility Meter, Model GMS-2. He also indicated that there was a problem with instrument drift and difficulty with obtaining a constant zero. We have since discussed this with Mr Stevens and it may be appropriate to indicate to all users of the GMS-2 that the best practice with this instrument, like other instruments of its type, is that the zeroing must be done in a noise-free environment. It should also be zeroed at relatively frequent intervals. A figure of zero or one should be obtained in this case.