1. China Ship Research and Development Academy, Beijing 100192, China; 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
Abstract:Wireless Electro-Magnetic Method(WEM)is a new artificial source electromagnetic sounding technique developed in the 1990s. In this paper, the origin of the harmonic of the transmitting electromagnetic signals in WEM was analyzed, and the apparent resistivity and phase were calculated by using transmitting signals and its harmonic with the data of experimentation. Based on a comparison of the two results, the authors considered that this technique is an effective method by using harmonic in the artificial source electromagnetic methods. It can improve work efficiency by decreasing transmitting frequency numbers or improve accuracy of interpretation by increasing frequency numbers of the electromagnetic response curves. This technique can be used in other artificial source electromagnetic methods because the harmonic always coexists with the transmitting electromagnetic signals in the source electromagnetic method.