摘要
本文应用非线性谱估计方法(MEM方法)、电/磁场脉冲能量统计方法,处理了四川汶川M_S8.0(2008)、新疆于田M_s7.3(2008)和青海玉树M_s7.1(2010)地震及强余震附近的地面电/磁场和Demeter卫星电离层磁场观测数据,研究了地震电/磁场变化,得到:在震中附近及周围出现了震前地电/地磁场极低频成分功率谱密度(PSD)增大、电磁脉冲能量增大的电/磁异常现象;在出现地面电磁异常的时段内,电离层磁场出现了PSD增大、磁脉冲能量增大的震前磁异常现象.最后,我们讨论了地面、电离层电磁异常现象的机制.
This paper studied the changes of the geo-electric, geo-magnetic fields around the Ms8. 0 Wenchuan earthquake in Sichuan （2008）, the MsT. 3 Yutian earthquake in Xinjiang （2008） and the Ms7.1 Yushu earthquake in Qinghai （2010） and their strong aftershocks, and the changes of the ionospheric magnetic field over the Wenchuan, Yutian and Yushu areas using the non-linear power spectrum estimation method （Maximum Entropy Method, for short ＂MEM＂） and the statistical methods of the electric/magnetic field pulse energy. Some significant geo-electromagnetic phenomena were seen, which included the increased power spectrum density （PSD） of the ELF components of the geo-electric and geo-magnetic fields, and the increases of the electromagnetic pulse energy of the fields recorded at the geo-electromagnetic disturbance stations and the geo- electric field stations. It is very interesting that such electromagnetic anomalous phenomena appeared on the ground as well as in the ionosphere in the same time period. Finally, we discussed the mechanism of the electromagnetic phenomena on the ground and in the ionosphere.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第11期2885-2897,共13页
Chinese Journal of Geophysics
基金
国家科技部支撑计划专题(2008BAC35B01-8)
国家科技支撑计划课题(2006BAc01802-04-03)资助
关键词
地震
DEMETER
电场
磁场
电磁扰动
Earthquake, Demeter, Electric field, Magnetic field, Electromagnetic disturbance
