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arXiv · 1512.05188

Seismic quiescence and b-value decrease before large events in forest-fire model

Tetsuya Mitsudo·Takahiro Hatano·Naoyuki Kato
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Abstract

Forest fire models may be interpreted as a simple model for earthquake occurrence by translating trees and fire into stressed segments of a fault and their rupture, respectively. Here we adopt a twodimensional forest-fire model in continuous time, and focus on the temporal changes of seismicity and the b-value. We find the b-value change and seismic quiescence prior to large earthquakes by stacking many sequences towards large earthquakes. As the magnitude-frequency relation in this model is directly related to the cluster-size distribution, decrease of the b-value can be explained in terms of the change in the cluster-size distribution. Decrease of the b-value means that small clusters of stressed sites aggregate into a larger cluster. Seismic quiescence may be attributed to the decrease of stressed sites that do not belong to percolated clusters.

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Tetsuya Mitsudo, Takahiro Hatano, Naoyuki Kato. 2015-11-12. Seismic quiescence and b-value decrease before large events in forest-fire model. https://arxiv.org/abs/1512.05188

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