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地震活动中存在着某些规律性结果(如指数律、幂律关系),并呈现一些前兆图象特征(如空区、条带).我们用细胞自动机模型模拟地震活动的某些规律和活动图象特征,分析产生一种或几种规律或特征的动力与介质因素,所得结果可作为它们的机理解释,为利用地震活动性预报地震的方法提供物理依据.本文通过引入断层和硬块体的存在,建立介质非均匀的细胞自动机模型.模型为二维细胞阵网格,每个细胞都具有一定的能量,能量的获取是随机的,而能量的传递和损耗是确定的,模型能得到与实际地震可比拟的地震事件,这说明了地震现象本质上的复杂性可能是随机性与确定性的统一体现.模型的演化过程分为三个阶段:初始阶段、增长阶段、自组织临界状态,我们给出各阶段的判断依据,并用自组织临界理论解释了各演化阶段的特征.模型成功地解释了Gutenberg-Richter 关系,但 Gutenberg-Richter 关系不能作为自组织临界现象的证据.通过对模型各演化阶段的特征分析,我们认为模型的演化过程体现了实际地震活动的周期性或轮回性特征.强震的震兆特征与其所在的阶段密切相关.强震前地震活动有两种形式:小震—活动增强—主震、小震—活动增强—平静—主震,对地震活动图象的研究表明:如果介质结构是均一的或过于复杂的,地震活动图象均不明显,只有在介质结构不均匀性相对规整、明确的情况下,地震活动图象可出现空区、条带等图形.如果不考虑介质结构的影响,只考虑动力学因素,地震活动图象演化的普示性特征是从无序走向有序.通过对模拟地震序列的分形分析表明:地震的时空分布和强度都呈现分形结构,特别是时空分布非均匀的多分形结构特征;中强地震前时空分布的多分维 D_q 值呈明显的下降趋势.
Some regular results (such as exponential law and power law) exist in seismicity and some precursory image features (such as vacant areas and bands) are presented.We used the cellular automaton model to simulate some laws of seismicity and The characteristics of moving images and the dynamic and medium factors that produce one or several regular or characteristic features can be interpreted as their mechanism to provide a physical basis for the method of seismic prediction using seismic activity.In this paper, , A model of cellular automaton with non-homogeneous medium is established. The model is a two-dimensional grid of cells, each cell has a certain energy, the energy is obtained randomly, and the energy transfer and loss are determined. The model energy The seismic event comparable with the actual earthquake shows that the inherent complexity of the earthquake phenomenon may be a unified manifestation of the randomness and certainty.The evolution of the model is divided into three stages: the initial stage, the growth stage, the self-organized criticality State, we give the judgment basis of each stage, and explain the characteristics of each evolution stage by self-organized critical theory.The model successfully explains the Gutenberg-Richter relationship , But the Gutenberg-Richter relationship can not be used as evidence of self-organized criticality.By analyzing the characteristics of the evolution stages of the model, we think that the evolution of the model reflects the periodic or recurrent characteristics of the actual seismicity. Which is closely related to the stage in which it is located.These seismogenic activities have two forms before the strong earthquakes: small earthquakes - enhanced activities - main shocks, small earthquakes - enhanced activities - calmness-main shocks, and studies on seismicity images show that if the medium structure is Uniform or too complicated seismic activity images are not obvious, only in the media structure is relatively regular, clear case, seismic images may appear empty areas, bands and other graphics.If you do not consider the media structure Only considering the dynamic factors, the general character of the evolution of seismicity image is from disordered to orderly.Through the fractal analysis of the simulated seismic series, it shows that the spatial and temporal distribution and intensity of the earthquake all present the fractal structure, especially the space-time The distribution of multi-fractal D_q values of the space-time distribution showed a significant downward trend.