云南ELF电磁观测资料的异常特征分析  

RESEARCH ON THE CHARACTERISTICS OF ANOMALIES IN ELF ELECTROMAGNETIC OBSERVATIONS IN YUNNAN PROVINCE

作　　者：孙维怀[1] 汤吉[2] 张平[3] 杨学慧[1] 

机构地区：[1]云南省地震局通海地震台,通海652700 [2]中国地震局地研究所,北京100029 [3]云南省地震局前兆台网,昆明650023

出　　处：《地震地质》2012年第3期488-499,共12页Seismology and Geology

基　　金：中国地震局2010年度地震监测;预报;科研三结合课题"超低频电磁观测在云南及邻区地震预报中的应用研究"资助

摘　　要：通过对云南省通海地震台2009年1月至2010年12月ELF电磁观测数据的处理分析,研究云南省及邻区中强地震前后,电磁场强度、视电阻率的变化特征。结果表明,1Hz、39Hz的电磁场功率谱在多次地震临震前分别比正常月份约大0.2～1.4个数量级。表现为在地震及余震序列中,电、磁场功率谱有明显的突跳,变化幅度与震级大小、震中距等有关;同时视电阻率的异常变化也比较明显。Located in an earthquake-prone region, the geological structures in Yunnan Province are complex. Taking into account that Tonghai County is located at the intersection of Xiaojiang Fault and Honghe Fault,an F-4M ELF electromagnetic instrument was installed at Tonghai seismic station, which has produced continuous reliable data. The author collected the data and information of the year 2009 ＆ 2010,and did analysis on the variation characteristics of both geomagnetic fields and electrical resistivity. The result shows that the 1Hz and 39Hz electromagnetic power spectra are 0.2 to 1.4 or- ders of magnitude higher than the normal values immediately before many earthquakes. The anomalies are represented by the abrupt changes of the electric and magnetic field power spectra in earthquake and aftershock sequences,and the amplitude of change is related to the size of earthquake magnitude and the epicentral distance. The electrical resistivity also changes obviously. So,further research on the anomalous characteristics of ELF electromagnetic data will be meaningful to the use of this instrument in earthquake prediction in the future.

关 键 词：ELF 电磁 功率谱 视电阻率 短临异常 

分 类 号：P631.325[天文地球—地质矿产勘探]