怀来台震前超低频电场与地震关系研究

STUDY OF ELECTROMAGNETIC RADIATION MEASURED AT HUAILAI STATION HEBEI PROVINCE AND ITS CORRELATION TO EARTHQUAKE

用河北省怀来电磁辐射观测台连续１１年观测资料，分析了张北－尚义６．２级地震前超低频电场资料的变化，研究了３００ｋｍ范围内Ｍｓ５．０以上地震和２００ｋｍ范围内Ｍｓ４．０以上地震前记录的超低频电场的变化。结果表明，异常信息量、异常起始时间及持续时间与震中距、震级有关，异常信息在地震发生前达最大值。

Ultra low frequency EM radiation continuously recorded data for 11 years at Huailai station,Hebei Province are analyzed.The anomalous change prior to Zhangbei Shangyi earthquake ( M s 6 2),and those prior to earthquakes with M s≥5 0,with an epicentral distance of less than 300 km are studied.The result shows that the amount of the anomalous change,the starting time and duration,have close relation to the epicentral distance and magnitude of an earthquake.The anomalous change reaches the maximum value prior to earthquakes.