Numerical analysis for dispersion characteristic from time domain induced polarization based on laboratory measurement data of complex resistivity

Induced polarization (IP) methods can be classified into time domain IP (TDIP), complex resistivity (CR), and Spectral IP (SIP) surveys based on measurement method. In field surveys, TDIP measurements are the most widely performed thanks to the easier and less time-consuming acquisition than SIP. In the meantime, SIP measurements are preferred over TDIP for the analysis on dispersion characteristics of CRs of cores in laboratory experiments based on Cole-Cole parameters. Theoretically, the dispersion characteristics should be common in SIP and TDIP measurements if the nature of used sources in both measurements is the same. However, in real situations, ranges of time and frequency are limited due to limitations of equipment resulting in dissimilarities between SIP and TDIP. Despite the dissimilarities, it is attempted to mutual interpretation between TDIP and SIP data sets in recent researches. We analyze spectral dispersions of CRs from laboratory measurements data of SIP to estimate SIP parameters based on the Cole-Cole model. Using the dispersion characteristics, numerical models with IP anomalies are constructed for numerical simulation of not only SIP but also TDIP surveys. Through inversion of resulting SIP and TDIP synthetic data, we estimate Cole-Cole parameters from inverted SIP anomalies and chargeability decay curves of the inverted anomalies from TDIP. Based on the numerical experiments, we make further numerical tests considering field scale mining and contamination surveys.

This work was supported by the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20194010201920) and Korea Ministry of Environment as "The SEM projects; 2018002440005"