中强地震前天祝电磁波信息变化的初步研究

PRELIMINARY STUDY ON INFORMATION CHANGE OF ELECTROMAGNETIC WAVE IN TIANZHU STATION BEFORE MEDIUM-STRONG EARTHQUAKES

分析了天祝电磁波观测资料在5次MS>4.0地震前的异常特征.结果表明一般地震前20天以内出现趋势异常变化,前兆表现为日均值由一位数突然上升到4位数以上.

The anomaly features in electromagnetic wave data of Tianzhu station before five MS>4.0 earthquakes are analyzed.The result shows that the trend anomaly appears from on to 20 days before mediumstrong earthquake,and its expression is,daily value rising suddenly from onedigit number to fourdigit number.