Laboratory measurements of electrical resistivity, polarizability and phase angle spectra of sulphide bearing rocks from captains flat N.S.W.

Abstract

Measured resistivities of sphalerite – galena – pyrite ores evince an inverse correlation with metallic mineral concentration whereas induced polarization parameters show a positive correlation. The resistivity of massive sulphide ore appears much greater than that of constituent minerals suggesting limited usefulness of geophysical methods which locate electrical conductors. The high polarizability of concentrated ores corroborates the applicability of induced polarization for locating massive sulphide deposits. The low resistivity and high polarizability of zinc rich samples suggest that sphalerite may contribute significantly to the electrical properties of lead–zinc–silver ores. Laboratory measurements of phase angle spectra suggest that this parameter may be of diagnostic value in surface and downhole variable frequency I.P. surveying.