井地电磁法勘探深度研究  

Research on the exploration depth of the borehole-surface electromagnetic field

作　　者：李亭亭[1] 王佳[1] 朱凯光[1] 

机构地区：[1]吉林大学仪器科学与电气工程学院,长春130061

出　　处：《地球物理学进展》2013年第1期373-379,共7页Progress in Geophysics

基　　金：吉林省科技支持计划工业高新技术重点项目(20110317);国家自然科学基金项目(41274076)

摘　　要：结合国家深部资源勘探的迫切需求,应用电磁场理论,从麦克斯韦方程出发推导出井地电磁场公式.通过两层大地模型与均匀半空间井地电磁场响应比较,研究了井地电磁法勘探深度,并给出了不同发射电流、发射频率、线源长度及两层大地电导率差异对勘探深度的影响,为井地电磁探测的野外勘探参数的选择奠定了理论基础.计算结果表明,加大发射电流、线源长度、两层大地电导率差异和降低发射频率可以增大接收信号的强度,提高有效勘探深度,从而,有利于进行深部资源勘探.The formula of the borehole-surfaee electromagnetic field is deduced for the urgent needs of deeper resource exploration, which applied the Maxwell equations of electromagnetic field theory. The paper have done prospecting depth simulation of borehole-surface electromagnetic, Meanwhile the research on exploration depth of the different emission current, launch frequency, length of line source and earth resistivity differenceis of two layers is conducted successfully through comparing the electromagnetic field response of the two layers earth model with uniform half space, which establish the theoretical basis for the actual field electromagnetic detection and will be conducive to the selection of parameters and instrument design in the field work. Results show that increasing emission current ,the length of line source, earth resistivity differenceis of two layers and reducing frequency can increase received signal strength and improve effective exploration depth. There will be helpful for deeper exploration. Therefore borehole-surface electromagnetic method will be faced with the broad application prospect in our country resources exploration.

关 键 词：井地电磁 勘探深度 发射电流 发射频率 线源长度 

分 类 号：P631[天文地球—地质矿产勘探]