An application of downhole electrodes in IP exploration

Abstract

A 45 m overburden layer having a conductivity 10 times that of the underlying host rock covers a sulphide body under study. It is estimated that this overburden will attenuate surface IP signal potentials to below 1/25 of that produced if the overburden is replaced by host material. By placing the pair of current electrodes down existing boreholes (75 m apart) at a depth of 1.6 times the thickness of the overburden this attenuation is completely overcome. Type curves showing diagnostic features are presented for traverses with potential electrodes remaining on the surface.