2011年11月1日尼勒克、巩留交界M_S6.0地震周期比研究

STUDY ON SEISMIC PERIOD RATIO OF NILKE、GONGLIU EARTHQUAKE WITH M_S6.0 ON NOV 1^(ST),2011

利用察布查尔地震台记录的资料,计算2008～2011年间察布查尔台附近MS≥2.0地震的周期比值,分析2011年11月1日新疆尼勒克、巩留交界MS6.0地震前孕震区时空演化特征。结果表明,周期比值在监视孕震区地壳介质变化方面有一定的效果,穿过震源区的地震波的周期比值在震前出现低值—回返—发震的过程。空间周期比值分布随着时间推移低值集中区有逐渐向中强震震中位置收缩现象。

Using records of Chabuchaer seismic station, this paper calculated period ratio of earth- quake with Ms≥2.0 near station from 2008 to 2011 and analyzed temporal-spatial evolution charac- teristics of seismogenic area before Nilke,Gongliu earthquake with Ms6.0 on Nov 1 st ,2011. The re- sults showed that： period ratio is quite effective on observing crustal medium in seismogenic area;the period ration of seismic wave across seismogenic area appeared low value to background before the earthquake. Period ratio in low concentration area concentrated to epicenter area with time lapse.