Adrian, J.FZJ* ; Tezkan, B. ; Candansayar, M. E.

2015

Abstract: An important matter of interest for the ore exploration with geophysical methods is the determination of the electrical resistivity and chargeability of the subsurface on the one hand and the assessment of the dimension of a potential ore deposit on the other hand. To make use of the advantages of electrical and electromagnetic methods, we applied the Direct Current Resistivity (DC) and Time-Domain Induced Polarization (TDIP) methods together with the Radiomagnetotellurics (RMT) method on a copper ore site in Turkey. While the DC method is sensitive to high resistive areas, the RMT method is sensitive to low resistive areas. Thus, the joint application of DC and RMT is expected to result in an improved picture of the resistivity distribution of the subsurface in contrast to the application of a single method. The TDIP method, on the other hand, is qualified to detect areas with disseminated sulfidic ores due to large electrode polarization effects which result in large chargeability anomalies. Since the presence of chargeable material effects the effective resistivity of the ground, it is advantageous to use the information of DC and RMT results as starting model for the TDIP inversion.On the poster we present the current state of the 2D DC/TDIP inversion algorithm that is being developed by the University of Cologne. It is a smoothness constraint inversion with an implemented forward algorithm that uses the finite element method with an unstructured mesh. The 2D inversion results from RMT and DC/TDIP data obtained during the survey on a sulfidic copper ore deposit in Turkey are presented. The presence of an ore deposit is indicated by areas with low resistivity and significantly high chargeability in the inversion models.This work is part of the BMBF/TÜBITAK funded project “Two-dimensional joint interpretation of Radiomagnetotellurics (RMT), Direct Current Resistivity (DCR) and Induced Polarization (IP) data: an example from ore exploration.”