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