地震监测人工源极低频电磁技术(CSELF)新试验  

New experiments of CSELF electromagnetic method for earthquake monitoring

作　　者：赵国泽[1] 王立凤[1] 汤吉[1] 陈小斌[1] 詹艳[1] 肖骑彬[1] 王继军[1] 蔡军涛[1] 徐光晶[1,2] 万战生[1] 汪晓[1] 杨静[1] 董泽义[1] 范晔[1] 张继红[3] 高妍 

机构地区：[1]中国地震局地质研究所,北京100029 [2]北京大学地球与空间科学学院地球物理学系,北京100871 [3]山东省地震局,济南250014 [4]黑龙江省地震局,哈尔滨150090

出　　处：《地球物理学报》2010年第3期479-486,共8页Chinese Journal of Geophysics

基　　金：国家公益性地震行业专项(2008419010);中央级公益性科研院所基本科研业务专项(DF-IGCEA-0608-2-15)资助

摘　　要：2009年利用大功率人工源极低频电磁技术(CSELF)在位于华北、华南、东北、西北和西南的12个地震台站和几个流动观测点进行了连续30天新的观测试验.结果表明,利用CSELF技术可以在1700 km之外测量到人工源电磁场信号,计算得到的电、磁场功率谱密度和视电阻率与天然源信号相比,抗干扰能力更强,观测信号更稳定,特别有利于识别和捕捉地震等诱发的电磁异常现象,在地震预测监测中具有很大的研究应用潜力.试验还发现,各地震台站和流动测点观测的CSELF信号的强度,与台站或者测量的电、磁场分量相对于发射源的距离、方位有明显的关系;发现在离开发射源的相对近区,场强随距离的衰减,比在相对远区更快;发现接收磁场信号比电场信号较易获得更高信噪比的数据.The new experiment of 30 days was carried out at twelve earthquake monitoring stations and a few mobile observatories located in North, South, NE, NW and SW China using Control Source Extremely Low Frequency （CSELF） electromagnetic technique in 2009. The measurement indicates that the artificial electromagnetic signals can be recorded at stations as far as 1700kin from the transmitter. The measured electric and magnetic fields and apparent resistivity using CSELF signals have much more powerful ability to resist the interference of cultural noise in comparison to natural electromagnetic signals. They are much more stable than those using natural signals, which is favorable to identifying the anomalous phenomena caused by earthquake. The experiment shows that CSELF is potentially valuable for earthquake research and prediction. It is also found that the recorded electric and magnetic component amplitude of CSELF signal varies depending on the distance and azimuth of the observatories relative to the transmitter. These amplitudes decline with increasing distance between observatory and transmitter faster within some space extent than those outside the extent. It may be easier for magnetic components to have higher ratio of signal to noise than for electric component.

关 键 词：人工源极低频电磁技术 电磁场 视电阻率 固体潮 地震监测 

分 类 号：P631[天文地球—地质矿产勘探] P315[天文地球—地质学]