文县地电场震前异常变化及其在2001年昆仑山口西M_S8.1地震预测研究中的应用

Abnormal variations of geoelectric field recorded at Wenxian station preceding earthquakes and their application to the prediction of the 2001 M_S8.1 Kunlun earthquake

在文县地电场观测系统中实现了地震异常信号与干扰信号的分离技术.长年的观测实践证明,文县地电场观测点是一个很灵敏的"地震窗口".研究表明,对于文县地电场观测点而言,震级、震中距、异常电信号幅度之间存在着线性关系;对带宽为0.003—30Hz的异常信号而言,震前异常的时间长短与异常开始至发震时刻的时间长短存在着密切关系,且与震中方位有关.这些关系为文县观测点预测未来地震时、空、强"三要素"提供了很有意义的经验公式,在给出昆仑山口西MS8.1地震预测意见中起到了良好的作用.

A separation technique between the seismic anomaly signals and noises was applied to the observation system of the geoelectric field at Wenxian station.The long-term observation of the geoelectric field at Wenxian station,Gansu province of China,shows that the site of the station is an ＂earthquake window＂.This study shows that there is a liner relationship among the earthquake magnitude,epicentral distance and abnormal signal amplitude of the geoelectric field recorded at Wenxian station.For the signals with bandwidth of 0.003--30 Hz,the duration time of the anomaly is related to the lead time and the azimuth of epicental location.These relationships offer an empirical basis for predicting the time,location,and magnitude of a forth coming earthquake based on the observations at the Wenxian station.These empirical relationships played an important role in an author＇s report on the prediction of the 2001 Kunlun MS8.1 earthquake.