Combination of geophysical methods for the exploration of deep high sulphidation epithermal deposits

Abstract

One of the current challenges in the discovery of high sulfidation epithermal type deposits is to identify the deposits that don´t outcrop, those that are deep or hidden. The objective of this research is to determine a combination of geophysical methods that allow vectoring towards deep resistive anomalies that are associated with silicified bodies with economic mineralization. The methodology was to systematically evaluate the geophysical programs of the Querco and Lucanas projects located in the Tertiary volcanic rock belt of Peru and to detail in chronological order how the application of geophysical methods was perfected in each project until determining the combination that allowed to generate more reliable and precise exploration targets. As a result, the unconventional Controlled Source Audio Magnetotelluric method (CSAMT) was identified, which has a range of depths greater than 300 m and defines prospective resistive anomalies with good resolution. But not all these identified resistive anomalies are associated with silicified bodies, as was shown by a subsequent magnetometry program, which found that several of these anomalies correspond to unaltered mafic subvolcanic units, discriminating in this way the prospective resistive anomalies from those that don´t present exploratory interest.