苍山5.2级地震前临沂台深井地电异常

DEEP WELL GEOELECTRICITY ANOMALY IN LINYI STATION BEFORE THE CANGSHAN MS5.2 EARTHQUAKE

摘要:

对苍山5.2级地震前距震中23km的临沂台深井地电观测资料进行了分析.结果表明,震前该台电阻率和自然电位出现了长达5年的与地震活动性异常同步的趋势异常.震前6个月电阻率出现下降异常.震前24天自然电位和电阻率同时急剧下降,震后又同时急剧回升.

Abstract:

Through analysis on deep-well geoelectricity data of Linyi station which is 23 km away from the epicentre of the Cangshan M_S5.2 earthquake,it is shown that before the earthquake,the background tendency anomalies of the deep-well resistivity and natural geoelectric potential appeared synchronously with the seismicity anomaly for 5 years.The descending tendency anomaly of deep-well resistivity occurred six months before the earthquake.The natural geoelectric potential and resistivity reduced rapidly 24 days before the earthquake,and then rose again abruptly after the earthquake.