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arXiv · 0911.1185

Asperity characteristics of the Olami-Feder-Christensen model of earthquakes

Hikaru Kawamura·Takumi Yamamoto·Takeshi Kotani·Hajime Yoshino
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Abstract

Properties of the Olami-Feder-Christensen (OFC) model of earthquakes are studied by numerical simulations. The previous study indicated that the model exhibits ``asperity''-like phenomena, {\it i.e.}, the same region ruptures many times near periodically [T.Kotani {\it et al}, Phys. Rev. E {\bf 77}, 010102 (2008)]. Such periodic or characteristic features apparently coexist with power-law-like critical features, {\it e.g.}, the Gutenberg-Richter law observed in the size distribution. In order to clarify the origin and the nature of the asperity-like phenomena, we investigate here the properties of the OFC model with emphasis on its stress distribution. It is found that the asperity formation is accompanied by self-organization of the highly concentrated stress state. Such stress organization naturally provides the mechanism underlying our observation that a series of asperity events repeat with a common epicenter site and with a common period solely determined by the transmission parameter of the model. Asperity events tend to cluster both in time and in space.

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Hikaru Kawamura, Takumi Yamamoto, Takeshi Kotani, Hajime Yoshino. 2009-11-06. Asperity characteristics of the Olami-Feder-Christensen model of earthquakes. https://doi.org/10.1103/physreve.81.031119

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