浅层瞬变电磁法在地铁工程隐伏断层勘探中的应用

Application of shallow transient electromagnetic method in concealed fault exploration of subway project

在地铁前期勘察中查明地铁路线上隐伏断层的分布情况对于地铁建设及后期运行具有重大的安全意义。基于城市地铁隧道埋深浅和勘探工作中外界干扰强的特点,本文将一种新型的浅层瞬变电磁法——等值反磁通瞬变电磁法应用于深圳市地铁13号线隐伏断层的探测工作中。依据测线反演电阻率断面图和对应测线上已知的地质资料进行综合分析解释,推断出线路上两处隐伏断层的分布范围。最后通过与钻探成果的对比分析,验证了该方法对地铁工程中隐伏断层的勘察具有一定的指导意义。

During subway geophysical prospecting,it is of great security significance to identify the distribution of concealed faults on subway route for subway construction and later operation.Based on the shallow burial depth of urban subway tunnels and the strong external interference in urban subway exploration,a new shallow transient electromagnetic method called opposing coils transient electromagnetic method（OCTEM） is applied to the detection of concealed faults in prospecting of Shenzhen Metro Line13.On the basis of inversion of the resistivity profile and the known geological data on the corresponding line,the comprehensive analysis and interpretation are carried out and the distribution range of the two concealed faults on the Metro Line 13 is deduced.In the end,through comparison and analysis with the drilling results,it is proved that OCTEM has certain guiding significance for the investigation of the hidden faults in the subway project.