Application of the multiplicative cascade model for the description of the seismic regime and for the seismic hazard assessment

Abstract

Seismic process is usually considered as a realization of the regime of self-organizing criticality (SOC-model). This model meets, however, definite problems, besides it gives only a statistical description of the seismic regime. The multiplicative cascade model (MCM) treats the seismic regime as an assemblage of randomly developing episodes of avalanche-like relaxation, occurring in a set of similar metastable sub-systems. In the simplest linear variant without memory the MCM is defined by the flow of events and by two parameters characterizing the hierarchical structure and the level of metastability of a geophysical medium. An advantage of such approach consists in a clear physical sense of character of the model. The MCM model b-value behavior is compared with the complex of typical anomalies revealed in result of examination of a large earthquake generalized vicinity (LEGV). The LEGV vicinity is constructed of earthquakes falling into the zones of influence of a large number (300, 500, or 1000) of largest earthquakes. The construction and examination of LEGV gives possibility to increase radically the available statistics, crucially diminish a random component of the seismic regime, and in result to reveal the typical features of pre- and post-shock seismic activity in details. The combined use of MCM and LEGV methods gives possibility to interpret a few features of the seismic regime and to suggest the typical scenario of the fore- and aftershock regimes of seismicity. The possibilities of application of the obtained results for earthquake prediction are discussed.