高密度电法与AMT在断裂构造调查中的综合应用

将音频大地电磁测量(AMT)和常规高密度电法相结合,综合利用两种方法的优点查找隐伏断裂构造具有较强的实用性。本文以龙门山断裂带隐伏断层调查为实例,首先介绍了工作区域的地电特征(判断是否具备开展电法工作的前提条件)、两种方法的工作原理及各自的数据处理流程,然后将同一测线上两种方法的测量成果加以对比,从而阐明两种方法各自的优缺点:AMT法测量深度大,但分辨率较低,高密度电法测量深度较浅,但分辨率高;AMT法易受外界电磁场干扰,而高密度电法易受水系、农田等低阻带影响。综上所述,二者在成果及适用范围上具有较高的互补性,在实际工作中适时地将两种方法结合起来,可以达到很好的效果。

Application of High-density Resistivity Method and AMT to the Investigation of Fault Structure

With the combination of audio-frequency magnetotellurics(AMT) and high-density resistivity method,it is more practical to find the hidden faults structure by using comprehensively the advantages of the two methods.In this paper,taking the investigation of buried fault in Longmen mountain fault zone as an example,it first introduces the geoelectric characteristics of working area(to determine whether there is a prerequisite to conduct electrical prospecting),the working principle of the two methods and the respective data processing flow.Then it compares the results of the two methods in the same line to clarify the advantages and disadvantages of the two methods:the AMT method has high measurement depth but low resolution,while the high-density resistivity method has low measurement depth but high resolution;the AMT method is susceptible to external interference of electromagnetic field and the high density resistivity method is easy to be affected by the low resistivity zone such as water system and farmland.In summary,the two are complementary to each other in the results and the scope of application.In practical work,it can achieve good results with proper combination of the two methods.