空基和地基近直流电场观测数据背景特征的相关性  

Correlation of near DC electric field background characteristic between space-based and ground-based observational data

作　　者：颜蕊[1] 王兰炜[1] 张世中[1] 胡哲[1] 张兴国[1] 刘大鹏[1] 朱旭[1] 张宇[1] 

机构地区：[1]中国地震局地壳应力研究所,北京100085

出　　处：《地球物理学报》2013年第4期1262-1273,共12页Chinese Journal of Geophysics

基　　金：中国地震局地壳应力研究所基本科研业务专项(ZDJ2011-6)资助

摘　　要：研究空基和地基电磁观测数据各自的特点和规律,并探索两者之间变化的相关性,对将空基和地基观测资料综合应用于地震监测研究具有重要的科学意义.本文利用法国DEMETER卫星的电场观测数据和我国甘肃天祝前兆科学试验台阵红沙湾地震台的水平地电场和垂直地电场、四川省地震局成都地震台的水平地电场的观测资料,重点对卫星和地面探测的近直流频段信号进行了综合分析.研究结果表明:(1)卫星直接观测记录的ULF电场观测值没有呈现明显的年变化趋势,但日侧和夜侧的Ez向(卫星运行速度的切线方向)观测数据呈现了一种长期的周期性特征,与地电场观测资料无相关性和同步性;(2)去掉卫星运行切割磁力线所造成的附加电场后所得的电离层电场与地面记录的地电场数据数量级相当,均集中在10-1～10-2 mV/m左右,两者具有可比性;(3)去掉卫星运行切割磁力线所造成的附加电场后,夜侧Ey(卫星轨道平面的法线方向)和Ez(卫星运行速度的切线方向)向的电离层电场数据均具有比较清晰的季节性变化趋势,呈现出较为稳定的年变周期,这与水平地电场的年变趋势一致.电离层电场和水平地电场在数量级和年变趋势上都呈现出明显的一致性.To explore and research the characteristics of the space-based and ground-based electromagnetic observational data and the correlation between them has important scientific significance for integrating satellite and ground electromagnetic monitoring data used in earthquake monitoring and research. In the paper, the near DC electromagnetic data recorded in DEMETER satellite, vertical and horizontal geoelectric field data recorded in Hongshawan station and horizontal geoelectric field data recorded in Chengdu station were comprehensively studied. The results showed that： （1）The ULF electric field observational data recorded directly by the DEMETER satellite did not show significant annual change trends; the observational data along the velocity vector direction both day side and night side present a longer-term cyclical characteristic, but there are no correlation and synchronization with geoelectric field observationaldata. （2）The magnitude of electric field data in ionosphere after removing the additional electric field value caused by satellite cutting magnetic line is consistent with geoelectric field data, and concentrated at about 10^-1- 10^-2 mV/m. （3） The concave annual seasonal change trend is displayed by the observation data along the normal to the orbit direction and along the velocity vector direction in night side, and showing a relatively stable annual variation period, this is consistent with the trend of the annual variation of the horizontal geoelectrie field. Therefore, both the magnitude and trends have shown the correlation and synchronization every year.

关 键 词：ULF电场 地电场 DEMETER卫星 背景特征 

分 类 号：P319[天文地球—固体地球物理学]