断层相互作用与地震触发机制研究回顾与展望

Fault interaction and earthquake triggering mechanisms: Progress and prospects

断层相互作用与地震触发关系研究是震源物理学领域的热点问题,能够帮助认识强震的孕育过程与物理机理,在地震危险性分析与预测研究中也有良好的应用前景.前人的综述文章从应力触发的基本原理、方法、适用性及多个震例研究的角度,提供了详细的阐述,然而从地震活动性分析这一角度对地震触发的介绍并不详尽,也未对这两个角度的结合和互补提供进一步的探讨.本文从物理模型和统计模型两个角度,综述了过去几十年针对断层相互作用和地震触发机制研究的成果与进展;通过介绍速率-状态摩擦律,展现这一科学问题的内在统一性,并对目前存在的问题和未来的可能研究方向进行了梳理和展望.从物理模型角度,着重分析了断层相互作用来源的几个重要机制:静态应力触发、动态应力触发和黏弹性应力触发,以及计算的基本原理和方法.在统计模型方面,介绍了地震活动性分析的基本原理和方法,重点分析了ETAS模型和b值在断层相互作用和地震触发机制中的应用.从两个模型结合的角度,指出两者互相验证的统一内涵以及速率-状态摩擦律的基本原理和方法.分析指出通过库仑应力计算和ETAS模型这两种不同的角度,可以综合研究多断层或地震之间的应力相互作用,并提供交叉验证,增加结果的可靠性;应用速率-状态摩擦律可以回溯性地研究地震序列的发生过程,为认识地震触发关系和断层相互作用提供了新的视角.

Research on fault interaction and earthquake triggering, which is a hot issue in the field of source physics, can facilitate understanding of the underlying mechanisms of strong earthquakes and also has good application prospects in earthquake risk analysis and prediction research. Previous review articles provided detailed explanations from the perspectives of basic principles, methods, and applicability, as well as multiple earthquake case studies of stress triggering. However, the introduction to earthquake triggering from the perspective of seismicity analysis is not exhaustive, and the combination and complementarity of these two perspectives are not provided in detail. This paper summarizes the achievements and progress of research on fault interaction and earthquake triggering mechanism through the past few decades from the perspectives of physical and statistical models. The current challenges and possible future directions are reviewed and evaluated. From the perspective of the physical model, three important mechanisms of sources of fault interaction are analyzed: static stress triggering, dynamic stress triggering, and viscoelastic stress triggering, as well as the basic principles and methods of calculation. In the aspect of the statistical model, the basic principles and methods of seismicity analysis are introduced, and applications of the epidemic-type aftershock sequence(ETAS) model and b-value in fault interaction and earthquake triggering mechanism are analyzed. From the perspective of the combination of these two models, the unified connotation of mutual verification and the basic principle of the rate-and-state friction law are introduced. The analysis points out that the stress interaction between multiple faults or earthquakes can be comprehensively studied through the two different schools of Coulomb stress calculation and the ETAS model and that cross-validation can increase the reliability of the results. Retroactive application of rate-and-state friction law can provide a new perspective for understanding the earthquake triggering relationship and fault interaction.