四川绵竹5.0级地震的电磁辐射前兆信息特征

在1999-09-14和1999-11-30绵竹两次5.0级地震前,位于四川省龙门山断裂带上的几个地表台和井下台分别接收到不同频段、不同形态、不同强度的电磁幅射异常信号。本文分析了地震前后电磁幅射信号由弱—强—弱—平静的变化过程,总结出震前电磁幅射异常信息具有持续时间长、范围大、信号强、信息组数多、信息减弱或平静后数天发震的特征。同时尝试用旋转ULF- 地表电磁波信息观测仪天线方位或转动地表DPJ- 点频电磁幅射仪接收天线位置的方法跟踪来波方位,取得较好效果。

Precursory Characteristics of Electromagnetic Radiation Abnormality in Sichuan before the 1999 M5.0 Earthquake

Before two seismic events with a magnitude of 5.0 occurring on Sep.14 and Nov.30, 1999 respectively, several stations located on the ground and in the well simultaneously received the abnormal signals of electromagnetic radiation with different frequencies, forms and magnitudes. This paper analyzes the electromagnetic radiation signals during the process of weak strong weak quiet variations before and after the earthquakes, and concludes that the abnormal information in electromagnetic radiation has the features of long lasting time, wide scope, strong signal, many information groups, decreasing signal and occurring earthquake in several days after a quiet period. At the same time, this paper tries to trace the wave direction by rotating the antenna direction of ULF Ⅲ ground electromagnetic information measurement equipment and changing the antenna location of DPJ Ⅲ dot frequency electromagnetic radiation instrument.