Analysis on Soil Resistivity Measurement Based on CSAMT

Abstract

Controlled Source Audio-frequency Magneto-telluric (CSAMT) that is used successfully in exploring coal, oil, gas and other resources is a way of geophysical technology, the most important feature of which is that only changing the frequency of field source can soil resistivity of different depth be obtained fully. Firstly, the basic principle of CSAMT for measuring soil resistivity is introduced, and then computer simulation models are built based on CSAMT and Schlumberger method which is accurate and used more nowadays to validate the effectiveness of CSAMT method. On condition of homogeneous half-space, the above models are realized by grounding analyzing engineering package CDEGS. The result shows that the soil resistivity measured by CSAMT can maintain constant in a wide range of frequency and is more close to real value; while the one measured by Schlumberger has a larger error and is even unbelievable when the frequency is higher. So the CSAMT method is more precise than Schlumberger method.