摘要
地震的孕育、发生和震后调整被认为是震源区及其邻区的应变积累释放过程.地震引起的静态库仑应力变化可有力地解释余震分布、强震序列等地震观测,并为探索地震发生机制和地震预测提供新的线索.地震学家们多采用弹性位错模型计算同震位错引起的库仑应力变化,以研究余震分布及地震间相互作用;随着流变学的发展,粘弹模型因可以很好的解释大量震后形变观测而被广泛用于断层面上的震后应力调整研究;此外,构造应力加载作用在更长时间尺度上造成断层面的应力积累,基于负位错模型计算震间库仑应力变化为又一研究内容.本文从同震、震后、震间库仑应力变化的角度提炼出断层面上库仑破裂应力变化的大量研究成果,介绍了库仑应力变化的基本计算原理及引起断层面上库仑应力变化的主要原因,论述了通过库仑应力演化来研究地震活动的方法和应用,进一步讨论断层面上库仑应力演化研究存在的问题和近期的进展.
Earthquake preparation, occurrence and post-seismic adiustments are generally considered to be a strain accumulation or release at focal and its surrounding regions. At the end of the 20th century, seismologists have yet understand the earthquake mechanisms comprehensively, Coulomb stress changes can be used to describe the trend of rock failure, and the calculations of static Coulomb stress changes caused by the earthquake can explain many seismic observations powerfully including aftershock distributions and earthquake sequences, and supplies clues to explore the earthquake mechanism to earthquake prediction. Earthquake process mainly includes co-seismic, post- seismic and inter-seismic stage, each of them accompanied by the Coulomb stress changes on the fault, thus affecting the spatial and temporal distribution of earthquakes. Initially, most of seismologists adopted elastic dislocation model to calculate the Coulomb stress changes caused by co-seismic dislocation, and applied it to the studies of aftershocks distribution and earthquake interaction; with the development of the theology, seismologists have found that viscoelastic relaxation could explain lots of post-seismic deformation observations, consequently, viscoelastic model was applied to the studies o{ stress adjustment on fault during the post-seismic period; however, in addition to the stress changes caused by earthquake, tectonic loading lead to stress accumulation on fault in long quiescent inter-seismic periods, negative dislocation model has been widely used in the calculation of the inter-seismic Coulomb stress changes. In this paper, and with a special section of co-, post- and inter-seismic Coulomb stress changes,we extracted many published works of Coulomb stress evolution on fault recently, briefed the basic calculation principle of Coulomb stress changes, then discussed the reasons causing the Coulomb stress changes on the fault, and analyzed the methods and applications of study seismic activity by Coulomb stress evolution. Though the
出处
《地球物理学进展》
CSCD
北大核心
2013年第1期132-145,共14页
Progress in Geophysics
基金
国家自然科学基金(41004040)资助
关键词
库仑破裂应力变化
同震位错
震后粘滞松弛
构造应力加载
Coulomb Failure Stress changes, Co-seismic displacement, Post-seismic viscoelastic relaxation, Tectonic loading
