Underground Tunnel Detection using EM Waves

Underground tunnel detection is a topic that has been explored in the past using a variety of methods, including electromagnetic methods such as ground penetrating radar. Here we explore tunnel detection using electromagnetic scattering from a tunnel. In the setup examined here, a radiating source (a vertical magnetic dipole, modeling a current loop transmitter) is inside of one borehole, while a receiver (a wire loop receiver) that is inside of a second borehole is used to receive an induced voltage. Changes in the received signal due to the presence of the tunnel are used for the detection.