Target discrimination with time‐domain spectral IP inversion

The west coast of Tasmania is a highly mineralised area with a wide variety of mineral deposits. A number of experimental geophysical surveys have recently been carried out as part of a government funded investigation of the mineral potential of this region. The surveys included in situ time domain spectral IP measurements. These were made over fresh and altered country rock, barren sulphides and black shales, as well as over the economic mineralisation. The data was analysed by fitting a single Cole-Cole dispersion to the observed data, using a modification of Marquardt's (1963) inversion routine. Excellent fits were obtained for more than 90% of the measurements.