1. The First Institute of Hydrology and Engineering Geological Prospecing, Anhui Geological Prospecting Bureau, Bengbu 233000, Anhui, China;
2. College of Geoexploration Science and Technology, Jilin University, Changchun 130026, China

The authors conducted full frequency apparent resistivity inversion, using frequency from 2^-3 to 2¹³ Hz, without near-field and transition area correction but directly using Cagniard apparent resistivity as inverse parameter. The electromagnetic fields of a long wire in horizontal layered media were obtained by using the virtual interface method in the forward modeling, where as the limited memory BFGS method was adopted for inversion. A three-layer model and the measured data were used for inversion and the inversion modeling results matched well with the real data, which validated the application of 1-D full frequency apparent resistivity inversion of CSAM.