应城地电场日变化及干扰特征分析

Analysis on characteristics of diurnal variation and interference of geoelectric field at Yingcheng Seismic Station

选取应城地电场观测数据,分析地电场日变化规律和数据干扰特征,得到以下结论:①应城地电场日变形态表现为两峰一谷,日变幅约15—30 mV/km;②应城地电测区环境不稳定,降水及高压直流输电干扰显著;③高压直流及雷电干扰会造成地电场观测数据曲线出现台阶变化,而雷电干扰数据表现为恒定值;电磁暴会引起观测数据曲线发生振荡变化,日变幅甚至可达正常幅度的10倍;降雨会导致观测数据出现突跳和漂移现象。研究结果有助于识别地电场数据干扰,剔除无效信息,更好地为湖北省地震监测服务。

In this paper,the observation data of geoelectric field at Yingcheng Seismic Station is selected to analysis its characteristics of diurnal variation and interference.The conclusions are as follows:①The diurnal variation of geoelectric field in Yingcheng shows two peaks and one valley and the amplitude of diurnal variation is about 15-30 mV/km;②The environment of geoelectric survey area in Yingcheng is unstable and the interference of rainfall and HVDC is significant;③The interference of HVDC and lightning will cause step change of observation data curves of geoelectric field and the data under the lightning interference is a constant value;The electromagnetic storm will cause oscillation of the curve and the amplitude of diurnal variation can even reach 10 times of normal.The rainfall will cause sudden jump and drift of the curves.The results will contribute to identify the interference,eliminate invalid information,and serve the earthquake monitoring in Hubei Province better.