The Study of Ultra-Low Frequency Electromagnetic Wave Exploration to Deep Geological Information

The source of passive ultra-low frequency(ULF),the elimination of noise,and the interaction of ULF with underground substances are discused and tested. The zero magnetic field experiment shows that the ULF received by instrument comes from the emission of underground object. Because of the complexity of the source and exploration situation,it's necessary for the received original ULF data to be filtered in order to get the clearer exploration curves which are less jammed. The exploration result of Tacan No.1 Well in Tarim Basin shows that the passive ULF technique can gain the deep geological information rapidly and accurately.