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本文讨论了地震断裂和构造应力之间的关系。首先综述了地震机制研究的结果,指出断层面解可以给出较好的断层面的取向,而得不到确切的应力场;认为地震是一个复杂的破裂过程,而P波初动只反映了破裂开始的状态。应用了库仑准则对地震断裂进行了讨论,得出在各向同性介质中,最大主应力与断层面的夹角α≤45°,断层面解只是它的一个特例,μ=0,即没有内摩擦,或相当于围压很高的岩石试验结果;在软弱面存在的情况下,断裂面与最大主应力的夹角可以分布在更大的范围内,可以大于45°,也可以小于45°,这范围取决于破裂参数S_w,μ_w以及中等主应力σ_2。讨论了震前应力变化的过程,指出了五种基本可能引起地震的过程。
This paper discusses the relationship between seismic faults and tectonic stress. First of all, the results of the study on the earthquake mechanism are summarized. It is pointed out that the fault plane solution can give a better orientation of the fault plane and can not obtain the exact stress field. It is considered that the earthquake is a complex process of rupture. However, The state where rupture started. The Coulomb criterion is used to discuss the seismic rupture. It is concluded that in the isotropic medium, the angle between the maximum principal stress and the fault plane is less than or equal to 45 °. The fault plane solution is only a special case of it. Μ = 0, Friction or equivalent to high confining pressure rock test results; in the presence of weak surface, the fracture surface and the maximum principal stress angle can be distributed in a larger range, can be greater than 45 ° can also be less than 45 ° , Which depends on the rupture parameters S_w, μ_w and the medium principal stress σ_2. The process of stress changes before the earthquake is discussed, and five basic processes that may cause earthquakes are pointed out.