摘要
2014云南盈江区域5月下旬接连发生了M_S5.6和M_S6.1级两个地震(双震),双差定位结果显示这次的盈江双震及其余震序列呈明显的时空聚集分布特征.本文基于波形互相关计算方法,挑选了盈江双震期间研究区内的重复地震事件,利用尾波干涉技术,分析地震序列持续期间地壳介质的物性变化.结果显示,在距离震源区较近的台站发现了盈江地震期间走时延迟的变化特征,随着流逝时间的不同,走时延迟变化复杂不一,这种变化可能源于不同路径上散射体的不同变化.其中,S波早期的尾波部分呈现明显的线性变化,可能是震源区附近地壳介质的波速变化所引起.研究发现,在两个主震之间和第二个主震之后走时延迟变化的特点不同,可能表示因不同地壳应力变化导致的介质性质变化.
In late May,2014, two strong earthquakes struck Yingjiang county,Yunnan province,China. After relocating this double earthquakes and it ＇s aftershocks by double-difference earthquake location algorithm we found temporal variations of earthquake distribution,Then we picked out repeating earthquakes based on cross-correlation technical and source separation calculated by Hypo DD,In the end,variations related to the strong earthquakes are detected by using coda wave interferometry technical in the station which is near to the hypocentral region. With the change of lapse time,time delay variations are very complex,it may related to the different variations of scatters in different paths. We found that the linear trend of delay time in early s wave coda are very obvious,it may indicate seismic velocity variations of underground media in epicenter area. We also found different variation of delay time during the 2 main shocks and after the second main shock,it may indicate different changes of underground media related to stress change.
出处
《地球物理学进展》
CSCD
北大核心
2016年第6期2421-2428,共8页
Progress in Geophysics
基金
国家自然科学基金(41174042)资助
关键词
盈江双震
地震重新定位
重复地震
尾波干涉
地壳介质动态变化
Yingjiang double earthquake
earthquake relocation
repeating earthquakes
coda wave interferometry
dynamic variations of crustal media
