OPTIMIZATION OF A 3-AXIS INDUCTION MAGNETOMETER FOR AIRBORNE GEOPHYSICAL EXPLORATION

The present work, develops a methodology to optimize the performance of conventional induction magnetometers (CIM) and develops a new concept in their implementation. From a logistic standpoint, the CIMs have to remain as small and light as possible. The use of permeable cores to concentrate the flux increases the apparent area and increases the sensitivity of the CIM. The dimensions of the permeable core affect the overall weight of the sensor and its performance. For permeable rod cores, the permeability is proportional of the length-to-diameter ratio. The novel idea developed in this work is to use an array of elemental induction magnetometers (EIM)s instead of a single CIM. The weight of the CIM is thus distributed amongst multiple EIMs and for the same weight there is substantial signal-to-noise ratio (SNR) improvements. There is also a decrease in the overall inductance which translates into greater bandwidths.

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