Inferring rate and state friction parameters from a rupture model of the 1995 Hyogo-ken Nanbu (Kobe) Japan earthquake

Mariagiovanna Guatteri; P. Spudich; G. C. Beroza

doi:10.1029/2001jb000294

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Inferring rate and state friction parameters from a rupture model of the 1995 Hyogo-ken Nanbu (Kobe) Japan earthquake

Mariagiovanna Guatteri·P. Spudich·G. C. Beroza

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Abstract

We consider the applicability of laboratory-derived rate-and state-variable friction laws to the dynamic rupture of the 1995 Kobe earthquake. We analyze the shear stress and slip evolution of Ide and Takeo's [1997] dislocation model, fitting the inferred stress change time histories by calculating the dynamic load and the instantaneous friction at a series of points within the rupture area. For points exhibiting a fast-weakening behavior, the Dieterich-Ruina friction law, with values of d c = 0.01–0.05 m for critical slip, fits the stress change time series well. This range of d c is 10–20 times smaller than the slip distance over which the stress is released, D c , which previous studies have equated with the slip-weakening distance. The limited resolution and low-pass character of the strong motion inversion degrades the resolution of the frictional parameters and suggests that the actual d c is less than this value. Stress time series at points characterized by a slow-weakening behavior are well fitted by the Dieterich-Ruina friction law with values of d c ≥0.01–0.05 m. The apparent fracture energy G c can be estimated from waveform inversions more stably than the other friction parameters. We obtain a G c ≈ 1.5×l0 6 J m −2 for the 1995 Kobe earthquake, in agreement with estimates for previous earthquakes. From this estimate and a plausible upper bound for the local rock strength we infer a lower bound for D c of about 0.008 m.

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Journal of Geophysical Research B: Solid Earth Article

Source-reported bounding extent: 34.13785614155759° to 34.83963667840105° latitude; 134.5356122351419° to 135.777067313268° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Mariagiovanna Guatteri, P. Spudich, G. C. Beroza. 2001-11-10. Inferring rate and state friction parameters from a rupture model of the 1995 Hyogo-ken Nanbu (Kobe) Japan earthquake. https://doi.org/10.1029/2001jb000294

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