利用非均匀细胞自动机模拟震级与应力降关系

地震 ›› 2011, Vol. 31 ›› Issue (2): 129-136.

利用非均匀细胞自动机模拟震级与应力降关系

李锰, 杨峰, 胡伟华

新疆维吾尔自治区地震局, 新疆乌鲁木齐 830011

收稿日期:2010-08-30 修回日期:2010-09-28 出版日期:2011-04-30 发布日期:2021-09-09
作者简介:李锰(1965-), 男, 河南淮滨人, 副研究员, 2002年获博士学位, 主要从事地质、工程地震及非线性理论在地学中的应用等研究。
基金资助:
国家自然科学基金项目(40774015)资助

Simulation of the Relation between Magnitude and Stress Drop Using Heterogeneous Cellular Automata Model

LI Meng, YANG Feng, HU Wei-hua

Earthquake Administration of Xinjiang Uygur Autonomous Region, Urumqi 830011, China

Received:2010-08-30 Revised:2010-09-28 Online:2011-04-30 Published:2021-09-09

摘要/Abstract

摘要： 为解释实际观测资料震源破裂过程与自相似(分形)模型的不一致性, 本文基于观测结果, 构建了由81×81个细胞单元组成二维非均匀断层模型, 并通过设计的细胞自动机模拟程序进行了模拟试验。研究结果表明: 断层结构非均匀性是影响孕震过程特征的重要因素, 而且地震强度分布并非简单的自相似。随着断层非匀质性增加, 破裂过程出现由相对的脆性破坏向塑性破坏特征变化的趋势。利用细胞自动机不仅能较好地解释震级-频度关系中的大、小震级段低头现象, 而且也可解释大震级事件具有相对恒定的应力降, 得到了与实际观测研究相一致的结果。

关键词: 细胞自动机, 非均匀性, 震级-频度关系, 应力降

Abstract: In the paper, three kinds of heterogeneous faults with 81×81 cells are set up using celluar automata models and simulated for explaining the inconsistency between the observations and fractal-based model. The results show that the G-R relations behave not in simple self-similarity but multi-fractal, and with the increasing of heterogeneity the fracture process tends to turn from brittle to plastic behaviors. At the same time, using the models can explain not only the curvature at smaller and larger magnitudes in G-R relation but also the relatively constant stress drop for larger magnitude earthquake events. Fault structural heterogeneity plays a important role in earthquake preparation process. The results from computer simulation are consistent with observations from detailed seismicity studies.

Key words: Cellar automata model, Heterogeneity, G-R relation, Stress drop

中图分类号:

P315

李锰, 杨峰, 胡伟华. 利用非均匀细胞自动机模拟震级与应力降关系[J]. 地震, 2011, 31(2): 129-136.

LI Meng, YANG Feng, HU Wei-hua. Simulation of the Relation between Magnitude and Stress Drop Using Heterogeneous Cellular Automata Model[J]. EARTHQUAKE, 2011, 31(2): 129-136.

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