Induced Polarization Effect in Rock Samples Collected from Submarine Hydrothermal Deposit

Abstract

This paper demonstrates that the generalized effective-medium theory of induced polarization (GEMTIP) can properly represent the induced polarization (IP) phenomenon in the rock samples collected from submarine hydrothermal deposit. The QEMSCAN mineralogical analysis is deployed in order to clarify the contents of minerals in the rock samples. The results of complex resistivity (CR) measurements show that the rock samples can produce strong IP effect, as expected from QEMSCAN results. The CR data are inverted for GEMTIP model parameters taking into account the results of the QEMSCAN analysis. The inversion algorithm is based on the hybrid method using the genetic algorithm with simulated annealing and the regularized conjugate gradient method (SAAGA-CG). The inversion results demonstrate that the GEMTIP model describes the measured CR data well, and represents the IP effect properly. These results open a possibility to discriminate the minerals by GEMTIP model parameters, because GEMTIP model parameters recovered from the inversion are different for different minerals. It is recommended that the IP effect has to be taken into account in interpretation of the marine electromagnetic data.