The rule of induction bow attenuation wave that is excited first field and formed in internal will be different with the difference of electric capability of geology body and existence position . so this method can resolve geology question and predigest consumedly research of geology object abnormity 随地质体导电性能及空间赋存位置的不同，感应涡流衰变的规律也有所不同，通过分析和研究二次磁场的时空变化特征，达到解决地质问题的目的，因而大大地简化了对地质目标体所产生异常的研究。
