The New Avalanche-Like Stochastic Model for Parameterization of Seismicity and Its Application to the South Sakhalin Island Seismicity

M V Rodkin,I N Tikhonov

doi:10.1155/2012/364318

Abstract

Seismic process is usually considered as an example of occurrence of the regime of self-organizing criticality (SOC). A model of seismic regime as an assemblage of randomly developing episodes of avalanche-like relaxation, occurring at a set of metastable subsystems, can be the alternative of such consideration. The model is defined by two parameters characterizing the scaling hierarchical structure of the geophysical medium and the degree of metastability of subsystems of this medium. In the assemblage, these two parameters define a modelb-value. An advantage of such approach consists in a clear physical sense of parameters of the model. The application of the model for parameterization of the seismic regime of the south part of Sakhalin Island is considered. The models of space changeability of the scaling parameter and of temporal changeability of the parameter of metastability are constructed. The anomalous increase of the parameter of metastability was found in connection with the Gornozavodsk and Nevelsk earthquakes. At the present time, high values of this parameter occur in the area of the Poyasok Isthmus. This finding is examined in comparison with other indications of an increase in probability of occurrence of a strong earthquake in the South Sakhalin region.

Highlights

Seismic process is usually considered as an example of realization of the self-organized criticality—the self-organizing criticality (SOC)-model [1,2,3]
Seismic regime is usually considered as an example of the regime of self-organizing criticality (SOC-conception)
The alternative statistical earthquake model (SEM) model treats the seismic regime as an assemblage of random episodes of avalanche-like relaxation, taking place at a set of uniform metastable sub-systems

Summary

Introduction

Seismic process is usually considered as an example of realization of the self-organized criticality—the SOC-model [1,2,3]. In terms of the SEM model, this feature points out the growth of probability of occurrence of a strong earthquake that has realized in the Nevelsk earthquake occurrence On this background the groups of events with anomalously high (>0.55) parameter p values are highlighted. In both cases, the events with metastability parameter p values exceeding 0.55 are given as red points. It should be noted that the intervals of time of nonlinear growth of a number of events and of released seismic energy (occurring in 2007-2008 and since the middle of 2010) correspond to the intervals of time of occurrence of events with higher (>0.55) values of parameter of metastability p in the Poyasok Isthmus area. One can conclude that the seismic regime behavior taking place in the Poyasok Isthmus area repeats the one that took place here before the strong Nevelsk earthquake and testifies for the increase of probability of a strong earthquake occurrence

Discussion

Conclusion