HR: 1340h
AN: NG33A-0168    [Abstracts]
TI: Time-Interval Statistics between Successive Earthquakes Based on Burridge-Knopoff Model
AU: * Hasumi, T
EM: t-hasumi.1981@toki.waseda.jp
AF: Department of Physics, Waseda University, 3-4-1, Ohkubo, Shinjyuku-ku, Tokyo, 169-8555 Japan
AB: Statistical properties of waiting time, time-intervals between successive EQs, have been recently discussed. Abe and Suzuki analyzed California and Japan EQ data and discovered a new scale-free nature of EQs. Namely, cumulative distribution of waiting time follows the Zipf-Mandelbrot power law. They also discussed the non-additive statistical mechanics viewpoint which was proposed by Tsallis. This mechanics is effective in a long-range interaction system. This new theory is based on the Tsallis entropy extended Gibbs-Boltzmann entropy with one parameter q which is represented the degree of interactions. As a result, they found that waiting time distribution also considered as q-exponential distribution in case of q>1, it is equivalent to maximum Tsallis entropy theory, moreover depended on the location and threshold of magnitude. This result suggested that there is an interaction between the successive EQs. In this presentation, we report numerical investigation about the two-dimensional spring-block model called Burridge-Knopoff (BK) model and discuss waiting time statistics. This model behaved like Self-organized Criticality (SOC) proposed by Bak et al. and was discussed b-value and other properties of EQ. We found three main results. First, the frequency distribution of waiting time shows the power law in spite of no aftershocks, and cumulative distribution also shows the Zipf-Mandelbrot power law. Second, this cumulative distribution depended on the friction property of surfaces and threshold of magnitude, hence frictional property might lead to the location dependency of distribution. Third, q increases as magnitude threshold increases. These results are satisfied with the observation result qualitatively and some of them quantitatively. It is conclude that EQ's system may seem to be a critical state, and two-dimensional BK model has a reality from a complex network viewpoint.
DE: 4430 Complex systems
DE: 4468 Probability distributions, heavy and fat-tailed (3265)
DE: 4480 Self-organized criticality
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
SC: Nonlinear Geophysics [NG]
MN: Fall Meeting 2005