降雨对阳原地震台地电阻率的影响

Influence of Rainfall on Earth Resistivity of Yangyuan

降雨对阳原地震台地电阻率有较大影响,地电阻率观测曲线下降幅度随着降雨量的增大而增大。经核实,在降雨后,地电阻率的快速下降变化与表层地电阻率下降及大秦铁路有关。地电阻率观测供电时,会有部分电流流向铁轨,造成观测值降低。降雨结束后,随着钢轨与大地的导电性减弱,地电阻率上升恢复。褶积滤波法可有效去除降雨的干扰,显示1991年忻州5.1级和大同5.8级地震前地电阻率的震兆信息。

Rainfall has great interference on the earth resistivity of Yangyuan seismic station,and the decline range of the earth resistivity observation curve increases with the increase of rainfall.It is verified that the rapid decline of earth resistivity after rainfall is related to the decline of surface earth resistivity and Daqin Railway.During the power supply of earth resistivity observation,some current will flow to the rail,resulting in the decrease of observation value.After rainfall,as the conductivity between the rail and the earth weakens,the earth resistivity increases and recovers.Convolution filtering method can effectively remove the interference of rainfall and highlight the earthquake precursor information of earth resistivity before Xinzhou M5.1 and Datong M5.8 earthquakes in 1991.