| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide underground-prospecting method and system that an accurately and simply measure and electromagnetic field by using a compact generator. SOLUTION: In a prospect method for measuring an electromagnetic field in the natural environment for obtaining underground specific resistance, each of earth rods 61 and 62 is arranged at separated two places, an insulation covering transmission line 8 is wired between the output terminal of a compact generator 7 and the earth rods 61 and 62, a frequency signal flowing in the transmission line 8 is used as a signal source, an electromagnetic constituent and a magnetic field constituent that are sum of a primary electromagnetic field being radiated from the transmission line 8 and a secondary electromagnetic field being generated from current being induced under the ground by the primary electromagnetic field are detected and are subjected to Fourier transformation, and the underground specific resistance is obtained according to the ratio of the electromagnetic component to the magnetic field component for each frequency component being obtained by the Fourier transformation.</p> |
