基于Swarm卫星数据的一次地震电离层现象辨识

The identification of a seismo-ionospheric phenomenon based on Swarm satellite data

为进一步探索基于多颗卫星观测数据的地震电离层现象识别,利用Swarm星座三颗卫星观测的电子密度数据和磁场数据,对已报道的2017年11月12日伊朗MW7.3地震震前第9天震中附近的一次地震电离层扰动现象进行辨识。通过分析三颗卫星相邻轨道的电离层扰动特征,获得了异常扰动存在的空间范围;利用Swarm星座三颗卫星轨道的时间和空间差异,计算出异常扰动在空间中可能的传播特征;使用同步观测的磁场数据判断其电磁辐射特性。最终根据现有对地震电离层耦合的认知,并结合分析的结果,认为该扰动为非震源发出的声重波扰动,非沿纬向传播的电离层行波扰动,非同步电磁辐射引发扰动,而是与伊朗MW7.3地震孕育活动无关的一次高纬度强烈电离层活动所引起的扰动变化。

In order to explore the identification of the seismo-ionospheric phenomena based on the data from several satellites,the electron density data and magnetic field data observed by three satellites in the Swarm constellation were used to analyse the ionospheric disturbances 9 days before the Iran MW7.3 earthquake occurred on November 12,2017. The spatial range of the abnormal disturbance was judged by analysis of the adjacent orbits data. The possible spatial propagation characteristics of the disturbances were calculated through the time and space difference of three satellites orbits of Swarm constellation. The electromagnetic radiation characteristics are determined by using synchronous magnetic field observation data. Finally,according to the current knowledge of seismo-ionospheric coupling and combining with the analysis results,we can come to this conclusion that the ionospheric disturbance was neither acoustic gravity wave(AGW) caused by seismic activity,nor the traveling ionospheric disturbance(TID) of the ionosphere,nor the disturbance caused by electromagnetic radiation,but a disturbance caused by strong high latitude ionospheric activity which is unrelated to the seismic activity.