2016年5月浚县地震台地电阻率EW向测值出现明显变化，为正确评价该变化，依据浚县地震台地质资料、岩层电性资料和EW向电测深曲线，将该台地下介质电性分布简化为二维电性结构，建立三维有限元模型。通过数值模拟，计算测区内地表铁轨干扰对地电阻率观测的影响形态和幅度。结果表明，由数值模拟所得干扰幅度、形态与实际测值的异常变化较吻合，因此从数值分析的角度确定了铁轨对浚县地震台地电阻率观测的干扰。
The apparent resistivity observation in East-West direction at Xunxian seismic station appeared abnormal changes in May 2016. In order to correctly evaluate the changes, based on the geological data, the electrical property of rock, and the East-West resistivity sounding curve at Xunxian Seismic Station, we established a three-dimensional finite element model by simplifying the electrical distribution of underground medium to a two-dimensional electrical structure. Through numerical simulation, the influenced morphology and amplitude of apparent resistivity observation by surface railway track interference in the survey area are calculated. The results show that the amplitude and morphology of the interference calculated by the numerical simulation are in good agreement with the abnormal changes of the actual observation. Thus, the interference of railway track to the apparent resistivity observation at Xunxian station is confirmed by numerical analysis.
2022,43(1): 86-91 收稿日期：2020-11-16
DOI：10.3969/j.issn.1003-3246.2022.01.012
基金项目：中国地震局监测、预报、科研三结合课题（项目编号：3JH-202001061）；中国地震局2020年度震情跟踪定向工作任务（项目编号：2020010413）
作者简介：路中慧，（1979—），女，本科，主要从事地震地球物理观测与分析工作。E-mail：lzhry@126.com
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