地震静态应力触发模型的全球检验  

GLOBAL TEST OF SEISMIC STATIC STRESS TRIGGERING MODEL

作　　者：万永革[1] 吴忠良[1] 周公威[1] 黄静[1] 秦立新[1] 

机构地区：[1]中国地震局地球物理研究所

出　　处：《地震学报》2002年第3期302-316,共15页Acta Seismologica Sinica

基　　金：地震科学联合基金 ( 6 0 2 0 0 5 )资助项目

摘　　要：运用 1 976～ 2 0 0 0年哈佛大学矩心矩张量目录 ,采用“地震对”概念对地震静态应力触发模型进行检验 .结果表明 ,从全球角度来看 ,地震静态应力触发效应确实存在 ,但只是一种很弱的效应 .将地震分为正断层、逆断层、走滑断层等分别对静态应力触发模型进行检验 ,发现非走滑断层地震具有明显的触发效应 ,而走滑断层地震触发效应则不明显 .按“地震对”中后续事件的延迟时间分为延迟时间 t≥ 1天、t<1天、t≥ 1 0天、t<1 0天和 1天≤t≤ 1 0天 5个时间段的“地震对”,分别对地震静态应力触发模型进行研究 ,发现静态应力触发效应在地震之后的短时间内不随延迟时间的变化而变化 .对全球不同区域的地震静态应力触发情况的研究表明 ,消减带“地震对”的触发效应较为明显 .为了研究地震静态应力触发模型在中国应用的可能性 ,对中国及邻区的地震进行了检验 ,发现就中国及邻区的地震类型而言 (以走滑断层为主 ) 。Seismic static stress triggering model are tested using Harvard centroid moment tensor (CMT) solution catalogue of 1976~2000 and concept of ″earthquake doublet″. Result shows that seismic static tress triggering effect does exist in the view of global earthquakes, but the effect is very weak. Dividing the earthquakes into thrust focal mechanism, normal focal mechanism, strike-slip focal mechanism, etc, earthquakes, we find that non-strike-slip focal mechanism earthquakes have significant triggering effect, whereas, the triggering effect in strike-slip focal mechanism earthquakes is not obvious. Divided the subsequent events delay time of ″earthquake doublet″ into 5 classes of t≥1, t<1, t≥10, t<10, 1≤t≤10 (t is in unit of d), seismic static stress triggering effect does not change with delay time in short time period after earthquakes. The research on seismic static stress triggering in different regions in the world indicates that triggering effect is significant in subduction belts. Seismic static stress triggering model is tested by using ″earthquake doublets″ in China and its adjacent. The result indicates that seismic static stress triggering effect cannot be observed easily in China and its adjacent due to the seismic focal mechanism type (most of the earthquakes are strike-slip earthquakes).

关 键 词：地震静态应力触发 静态库仑破裂应力变化 哈佛矩心矩张量目录 地震活动性 地震对 

分 类 号：P315.5[天文地球—地震学]