The Electromagnetic Response Of Magnetically Permeabie Non-Conductors

Electromagnetic prospecting has been carried out for many years using<br>various field systems. In the past the targets of concern were assumed to<br>have high conductivities and to be located in resistive or mildly conductive-<br> host rocks. Generally it was further assumed that the magnetic<br>permeability was constant throughout the region and had the same value as<br>that of free space (411 x io-7 h/m). Electromagnetic systems using a magnetic field as a source will also produce induced magnetizations in<br>magnetically susceptible parts of the earth in the area of investigation.<br>These magnetizations will affect the primary field and produce observable<br>responses under certain conditions.