CAJ | 학술논문

汶川5.12大地震发生后,在武都汉王地震台及其附近地区布置了2个大地电磁测深点,进行了两期余震序列的地震电磁效应连续监测,共观测到M_s4.0及以上的余震事件35次.通过与汉王强震台的地震记录数据中15个强震记录比较发现,与地震波相对应的地震同震电磁信号存在于所有的电场和磁场记录分量中,它们与地震波到达同步.地震破裂发生时的电磁辐射信号在记录数据中相比地震波达到观测点的电磁信号幅度要小得多,无法从观测数据识别出来.通过分析对比地震位移和同震电磁信号的关系,提出了地震电磁同震信号产生的地震波驱动机理,认为观测系统在地球基本磁场中随地面运动产生了地震同震电磁信号,并从观测的地震振动位移和电磁信号进行了验证.
문천5.12대지진발생후,재무도한왕지진태급기부근지구포치료2개대지전자측심점,진행료량기여진서렬적지진전자효응련속감측,공관측도M_s4.0급이상적여진사건35차.통과여한왕강진태적지진기록수거중15개강진기록비교발현,여지진파상대응적지진동진전자신호존재우소유적전장화자장기록분량중,타문여지진파도체동보.지진파렬발생시적전자복사신호재기록수거중상비지진파체도관측점적전자신호폭도요소득다,무법종관측수거식별출래.통과분석대비지진위이화동진전자신호적관계,제출료지진전자동진신호산생적지진파구동궤리,인위관측계통재지구기본자장중수지면운동산생료지진동진전자신호,병종관측적지진진동위이화전자신호진행료험증.
The measurement of electromagnetic field at two sites in Hanwang and Chouziba for monitoring aftershock series has been done in continuous observation after the M_s8.0 Wenchuan earthquake on May 12, 2008. The measurement was done in two periods. Recorded data covered 35 aftershocks with magnitude more than M_s4.0. Comparing with the seismic data recorded at Hanwang station for 15 events, the coseismic signal of aftershocks exists on all components of the magnetic and electric fields at two different sites. The EM coseismic signals arrived simultaneously with the seismic waves,but not at the origin time of the earthquake. The signal produced at the origin time of the earthquake is much smaller than coseismic signal of the waves. It can't be identified from the time series. In addition, the generation of coseismic electromagnetic signals can be explained by earthquake dynamo mechanism. Analysing and comparing the relationship between the seismic displacement and EM coseismic signals,the mechanism of EM coseismic signal generation appear to be driven by seismic waves. That is,the EM observation system set up in geomagnetic field moved with the ground motion so that the EM coseismic signals were produced. The observations of seismic displacement and electromagnetic signals verified it.