The developments in deep earth exploration are promoted by advanced methods and corresponding high-end detection instruments [1], wherein a single geophysical exploration approach can yield multiple solutions. In the mid-nineteenth century, scientific methods were first used to investigate the earth's internal structure. In an initial attempt at seismic exploration, R. Mallet, in 1845, used artificially excited seismic waves to measure the propagation speed of elastic waves in the earth's crust [2], [3]. In comparison to the seismic method, the use of electromagnetic approaches has been very limited. In 1955, a Soviet scholar Tikhonov and a French scholar Cagniard proposed a geophysical exploration method called “Magnetotelluric (MT) Sounding,” which employs natural alternating electromagnetic fields to study the earth's electrical structure [2]–[4]. To address the limitations like natural-field source randomness and a weak signal associated with MT, D. W. Strangway and M. Goldstein proposed a detection method using artificial sources (CSAMT) in the early 1970s [5], [6].