地震电离层VLF电磁场频谱特征研究  

RESEARCH ON FREQUENCY SPECTRUM CHARACTERISTICS OF VLF ELECTROMAGNETIC FIELD IN EARTHQUAKE IONOSPHERE

作　　者：张建国[1,2] 姚丽[3] 刘晓灿[3] 马新欣[3] 焦立果[3] 

机构地区：[1]中国科学技术大学地球和空间科学学院,合肥230026 [2]河北省地震局邯郸中心台,邯郸056001 [3]中国地震局地球物理研究所,北京100081

出　　处：《大地测量与地球动力学》2012年第3期110-115,共6页Journal of Geodesy and Geodynamics

基　　金：河北省地震局重点项目"河北地区电磁场动态演化特征研究";中央级公益性科研院所基本科研业务专项(059217);国家科技支撑项目(2008BAC35B01)

摘　　要：对2006年3月—2009年2月DEMETER卫星VLF电磁场频谱数据的分析发现,全球地震电离层电磁场频谱有以下特征:50～300 Hz为地震电离层效应的优势频段;距离地震空间位置越近,地震异常越显著;不同半球的地震,异常方向和方位不同;对地磁夏季北半球地震的研究表明,海洋地震主要为正异常,陆地地震为负异常;地磁夏季,不同半球地震的磁场频谱异常显著不同,北半球的正异常偏南,而负异常偏北,南半球的负异常偏东北,而正异常偏西南。By analyzing the electromagnetic spectrum data observed by DEMETER satellite during the time in- terval between March 2006 and February 2009, it is found that the characteristics of electric field power spectrum of global ionosphere in DEMETER altitude are as follows ： the 50 - 300 Hz frequency band about earthquake ionospher- ic effect are the dominant frequency the closer, the distance to seismic spatial position, the more significant seismic anomaly ; indifferent hemispheres of the earthquake, abnormal azimuthal direction is different. The studies on the e- vents in northern hemisphere in geomagnetic summer show that the anomaly corresponding marine quakes occured in geomagnetic summer the frequency spectrum anomaly of geomagnetic field basically were positive and these land negative and corresponding the quakes in different hemisphere were significantly different：these in the northern hemisphere were positive and meridional, and negative anomaly of north but negative anomaly opposite in the south- ern hemisphere, the negative anomaly were northeast and positive ones southwest.

关 键 词：DEMETER卫星观测 电离层 VLF电磁场频谱 全球异常特征 地磁夏季 

分 类 号：P315.721[天文地球—地震学]