Induced polarization with in-loop transient electromagnetic soundings: A case study of mineral discrimination at El Arco porphyry copper, Mexico

With the inversion of in-loop transient electromagnetic (TEM) soundings over the El Arco porphyry copper deposit in terms of one-dimensional Cole–Cole dispersive models we found that the relationship between the chargeabilities and the time constants shows a fair agreement with the actual mineral concentrations measured in drillhole cores. This is the first reported case of mineral discrimination with this technique. Through a sensitivity analysis we show that these two parameters are the least well resolved.