基于应变率场的全球地震活动特征模拟探索

A Preliminary Simulation of Global Seismic Activities based on Global Strain Rate

本文提出利用全球应变率资料模拟全球地震活动特征的基本思想,并作了初步探索。利用GSRM的全球应变率场结果,初步设计了模拟全球地震活动时空分布特征的细胞自动机模型。该模型把地球考虑为一个自组织的整体系统,制定了细胞自动机的演化规则,获得了模拟的人工地震目录。初步的模拟结果基本反映了全球地震活动的主要分布特征,体现了全球构造活动强弱的主要格局,初步达到了利用GPS等实测资料计算的应变率作为细胞自动机网格状态及其改变量来模拟复杂的全球地震活动特征的实验目的。

Relationship between strain rate field observed by GPS and global distribution of strong earthquakes is analyzed in this work.How to recognize the characteristics of global seismic activities with space observation technology？ A preliminary model of cellular automata that could simulate the global seismic activities both in time and space has been established based on the results of global strain rate field provided by GSRM Program.The grid of the model is evenly divided,which is consistent with that of GSRM.Status of each cell is its strain state,and its adjustment is according to the evolution rules.Maximum shear strain criterion is adopted in the evolution of the cellular automata.The threshold for cells in surface expansion is 80％ of that for those in compression.The preliminary model could in general simulate the main characteristics of the distribution of the global seismic activities.It could exhibit in general the global distribution of weak and active tectonic activities.Although the preliminary cellular automata model needs to be improved in many aspects,the result suggests the possibility of modeling the general features of the rather complicated global seismic activities based on the strain rates obtained by GPS and other observations.