Advanced field magnetometers comparative study

Abstract The application of flux-gate and search-coil magnetometers for geophysical prospecting is more and more widespread. The physical principle of their operation determines their use for the measurement of weak magnetic fields in the frequency band where their sensitivity threshold is lower: from DC to some tens of Hz for flux-gates and from some fractions of Hz till ∼1 MHz for search-coils. The estimation of the noise level of both types of magnetometers is made and recommendation for choice of ELF band is given. The problems connected with the digital measuring system are analyzed and new errors arising in the digital structure are outlined. The main parameters of recently developed flux-gate and search-coil magnetometers are discussed.