The major challenge associated with understanding petrophysical data is not making the measurement, but rather understanding the results. Several case studies are presented where the petrophysics have determined not only which geophysical techniques to apply but whether a geophysical target has indeed been tested.

For example, the sedimentary textures associated with sediment hosted copper mineralisation can compromise the inductive conductivity and resistivity response (anisotropy). Chargeability highs associated with porphyry copper mineralisation is indicative of disseminated pyrite in the propylitic and pyrite +/- chalcopyrite +/- bornite in the potassic alteration zones and higher chargeability does not necessarily mean more copper. Drill testing EM plate approximations for nickel sulphide and volcanogenic massive suphide (VHMS) whether an EM conductor has been intersected. In most porphyry systems magnetite is coarse grained, therefore a world class porphyry deposit should not have dominant remanent effects and skarns.