地震前几周、几天、几小时甚至几分钟,电磁场的强度、相位或者谱密度等将发生异常变化,电离层的电子、离子浓度和温度等会发生异常扰动,这些现象的出现向人们发出地震即将来临的信号、这些现象不仅在地面可观测到,在卫星上也能观测到,它们在确定异常现象发生的地点和时间等方面具有各自的优势,把两种观测相结合,对异常信号进行立体监测,是实现地震预测预报的发展趋势、至今,对地面观测已经进行了大量的研究和实践,利用卫星进行观测近几年刚刚开始,但已经显示了它监测地震异常的独特能力,引起各方面的高度重视,成为各国建立立体预警系统不可缺少的组成部分.本文重点介绍利用卫星等观测空间电磁异常现象的研究结果.
Anomalous amplitude, phase and power spectrum of electromagnetic field can occur during a few weeks, days, hours and/or minutes before earthquakes. The disturbance of density and temperature for both of electron and ion in the ionosphere can also exist in these time periods. These phenomena can be observed not only on the earth surface but also by satellite. The different advantages on determination of place and time of earthquake occurrence are appeared by using the data observed on the earth surface and by satellite respectively. The combination of these two kinds of data and establishiment of cubic monitoring system is a tendency. The great lot of study on the data obtained on earth surface has been carried out. The observation by satellite has been just started recent years but its potential ability has been appeared which is going to become a necessary part of monitoring prime of warning signal transmitted by earthquake preparing. This paper will outline the research results on the electromagnetic anomalies observed by satellite.