Resistivity tomography based on multichannel electrodes

Abstract

With the constantly changing engineering construction sector, the detection accuracy of conventional electrical resistivity tomography (ERT) is no longer sufficient. A multichannel electrode design (MERT)-based ERT is introduced in this paper to address the growing need for resolution. The imaging accuracy of the ERT method is improved through the collection of apparent resistivity data in various directions by measuring the potential difference between different channels. Numerical simulation results of the inclined high-resistivity anomaly model reveal that MERT is a precise representation of the shape, inclined direction, and buried depth of the anomaly, with thoroughfare M₂N₂ producing the most precise forward and inverse results. Based on the analysis results of the model resolution matrix, when the buried depth of power supply points and the gap between potential acquisition points are 30%–90% and 30%–60% of the electrode distance, respectively, the MERT approach yields superior detection outcomes. The detection effect of the MERT method on anomalous bodies with different burial depths under the optimal parameters also indicates that the MERT method can obtain richer potential change information with higher resolution in deep areas compared to the ERT method. With the implementation of the MERT approach, the scope of applications for ERT is expanded, the accuracy of ERT detection is increased, and the progress of near-surface fine detection is positively influenced.