多闭锁点地区地震预测唯象模型

THE SIMULATION METHOD OF EARTHQUAKE PREDICTION IN THE REGION-WITH A GROUP OF LOCKED-POINTS

由于地震现象的复杂性．目前还写不出地震动力学方程组，但是，基于唯象物理模型方法，却可以建立起唯象地震模型来映射地震活动的基本规律，从而研究地震动力学过程．本文用闭锁点区来唯象地模拟智利型海沟地震的力学孕育机制．认为：各闭锁点之间由“软材料”隔开．当某闭锁点发生‘粘滑”地震时，该闭锁点附近的“软材料”也会具有一定的瞬时抗剪能力，但随着时间推移，‘软材料’抗剪能力逐渐下降，其所承担的剪力向其它闭锁点转移，形成新的应力集中．每个闭锁点的地震应力由：上次地震的残余应力、板块持续构造运动的应力积累、其它闭锁点地震‘转移’过来的地震应力三部分组成．按照这种思想，地震活动的空间相关性得到了较大程度的考虑．基于上述观点，本文分析了纬度２０Ｓ～４０Ｓ智利海沟部分近２０年内的地震危险性．

Because of the complication of earthquake phenomena, it is difficult to give theearthquake dynamic equations. However, based on the simulation methods, it's possibletO set up the simulation models so that the earthquake breeding process is mapped. In thispaper, a group of locked--points are used to simulate the earthquake breeding process. It issupposed: there is the 'soft--medium' between the locked--points. When a locked--Pointbreaks up, the soft--medium nearby has the ability to bear the slip force in a very short period. However, the slip force will gradually move to other locked--points, this will bringabout the new concentration of seismic stress. According to the above ideas, theearthquake space-time coherence is considered to some extent. In this paper, the seismicrisk of fault zone is analysed.