The 2010 Chile Maule earthquake ranks as the sixth largest earthquake ever recorded by a seismograph.In this paper,based on the parallel finite element method,the heterogeneous ellipsoidal earth model including topography,Moho discontinuity is setup to investigate the coseismic effect resulted from the 2010 Maule earthquake.Based on the Coulomb stress change,seismic activity of surrounding faults and triggering of aftershocks are estimated.The results show that:the effects of Earth's layered structure and curvature on co-seismic horizontal and vertical displacement are significant in the case of 2010 Maule earthquake.The plane model may underestimate the far-field co-seismic displacement and strain near the equator,overestimate and underestimate the far-field displacement and strain near Antarctica,respectively.If the effects of laterally heterogeneous medium and topography are neglected,co-seismic stress drop will be significantly underestimated,the error of the near-field east-westward and north-southward stress will be up to 95.4％ and 90.8％,respectively.The Coulomb stress change in Illapel region is equivalent to 15 years' tectonic stress accumulation,which means the Maule earthquake hasten the failure of 2015 Illapel earthquake.Coulomb stress changes on optimally orientated faults are estimated,70.9％ of aftershocks occur in regions where the failure stress exceeds 10 kPa.The Mw6.9 and Mw7.0 aftershocks near Pichilemu were triggered by the great Maule earthquake.%2010年智利Maule大地震是人类有观测记录以来第六大地震,基于高性能并行有限元方法,建立含地表地形和Moho面起伏的大规模非均匀椭球地球模型,计算了该地震同震效应,并根据库仑应力变化分析周围断层地震活动性和主震对余震的触发关系.结果表明:对于2010年Maule地震,地球曲率和层状结构对同震水平位移影响不可忽略,如果不采用球面分层模型,在低纬度远场可能会造成位移和应变量值均被低估,在高纬度远场可能会造成位移被夸大而应变被低估.如果不考虑介质横向不均匀和地形,同震应力降被显著低估,近场同震东西向应力变化误差最高95.4％,南北向应力变化误差最高90.8％.Illapel地区库仑应力变化约10 kPa,相当于15年构造积累,Maule地震加速了2015年Illapel地震发生.以最优破裂方向投影得到库仑应力变化,经统计70.9％余震落在库仑应力变化量值大于10 kPa区域.本次特大地震触发了Pichilemu附近Mw6.9和Mw7.0两次正断型余震.
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