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arXiv · 0712.1303

Aftershock identification

Ilya Zaliapin·Andrei Gabrielov·Vladimir Keilis-Borok·Henry Wong
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Abstract

Earthquake aftershock identification is closely related to the question "Are aftershocks different from the rest of earthquakes?" We give a positive answer to this question and introduce a general statistical procedure for clustering analysis of seismicity that can be used, in particular, for aftershock detection. The proposed approach expands the analysis of Baiesi and Paczuski [PRE, 69, 066106 (2004)] based on the space-time-magnitude nearest-neighbor distance $η$ between earthquakes. We show that for a homogeneous Poisson marked point field with exponential marks, the distance $η$ has Weibull distribution, which bridges our results with classical correlation analysis for unmarked point fields. We introduce a 2D distribution of spatial and temporal components of $η$, which allows us to identify the clustered part of a point field. The proposed technique is applied to several synthetic seismicity models and to the observed seismicity of Southern California.

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BibTeXRIS

Ilya Zaliapin, Andrei Gabrielov, Vladimir Keilis-Borok, Henry Wong. 2007-12-08. Aftershock identification. https://doi.org/10.1103/physrevlett.101.018501

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