Electrical resistivity tomography with new arrangement of electrode system for grottoes

Abstract

Various fractures were formed around the grottoes resulted from climate and human factors. They cause damage to cultural relics and have a significant impact on cultural relic protection. Detecting the internal structure of grottoes becomes the premise of grotto protection. The electrical resistivity tomography (ERT) method is often used in near-surface geophysics. ERT has the advantage of stability and accuracy. It is an important method in grotto structure detection. For the limited detection ability of the traditional surface ERT method and borehole-to-surface ERT method on the cliff of grottoes, we propose a combined arrangement of electrodes named the borehole-to-surface-to-cliff ERT(BSC-ERT) method for grotto detection using surface, borehole and cliff electrodes. According to the simulation analysis, the BSC-ERT method is suitable for the structure detection of grottoes, and this method has a more extensive and more reasonable detection range and a better result.