Three-dimensional observation system of direct current method based on overlapping electrodes and its application

The three-dimensional (3D) direct current (DC) method for geophysical prospecting has benefits such as precise spatial positioning and sensitivity to low-resistivity bodies. However, its efficiency in large-area exploration is limited by the need for numerous survey lines. Traditional electrical instruments with high density increase measurement times and decrease efficiency. We present a novel strategy to address this by utilizing parallel electric method acquisition technology. The deployment of multiple observation systems with overlapping electrodes allows for the extraction of potential data differences between measuring electrodes along various survey lines, resulting in a combined dataset that resembles a true 3D observation system. This novel setup reduces the requirement for excessive acquisition equipment while enhancing working efficiency, particularly in challenging environments such as mines. Numerical simulations demonstrate the system’s practicality in balancing the accuracy of anomaly localization achieved by true 3D and pseudo-3D observation systems. Its application at the Weah Power Plant in Guizhou Province showcases its effectiveness. It successfully explored a mined-out area of a small coal mine, yielding fruitful results.