Surface Magnetic Resonance Sounding Using Electrical Source for Subsurface Aquifer Modeling

Surface magnetic resonance sounding (SMRS) is a unique geophysical method that can directly track and quantify groundwater using the remote sensing technique. The conventional SMRS used a closed coil as the magnetic field source. In the field measurement, a large-size coil is laid on the ground or even multiple coils are set for array detection. This reduces the detection efficiency and consumes labor inevitably. The current study proposes an electrical source (ES), a new mode for exciting the groundwater. It is a long wire placed on the ground and connected to the Earth by two grounding electrodes. The ES has the advantages of labor-saving, time-saving, and better environmental adaptability. Moreover, the magnetic field generated by the ES can transmit farther than the traditional magnetic source. Based on this, we matched different receivers for the ES and simulated the kernel, the resolution, and the signal with different configurations. The results show that using the long grounding wire as both the electrical transmitter and receiver can obtain higher signal amplitude and better resolution than the traditional magnetic configuration. In addition, it has the ability to break through the detection depth of the conventional method.