Reconstruction of seismic faulting by high‐velocity friction experiments: An example of the 1995 Kobe earthquake

Abstract

[1] High-velocity friction experiments on a fault gouge collected from the Nojima fault activated during the 1995 Kobe earthquake showed that the friction coefficient decreased from 0.63 to 0.18 over a slip weakening distance, D c , at high slip rates of $ 1 m/s. The dramatic drop in friction coefficient of more than 0.3 is consistent with that for the Kobe earthquake estimated from seismological observations. Experimentally determined D c becomes 5 m at a higher normal stress of 1.85 MPa, close to the order of magnitude of seismologically determined D c of 0.5 to 1 m. The difference in D c is not significant because the fracture energy consumed during frictional slip is the same order of 10 6 N/m for both cases. Here we show that frictional behavior of a fault during an earthquake can be predicted by conducting high-velocity friction experiments. Citation: Mizoguchi, K., T. Hirose, T. Shimamoto, and E. Fukuyama (2007), Reconstruction of seismic faulting by high-velocity friction experiments: An

Constitutive parameters for earthquake rupture dynamics based on high-velocity friction tests with variable sliprate

“…It should be noted that Eq. 2 is identical to the definitions made by Hirose and Shimamoto (2005) and Mizoguchi et al (2007). Since we used solid cylindrical specimens without hollows, we set the inner radius of the specimen to zero in their formulation.…”

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Clay‐clast aggregates: A new textural evidence for seismic fault sliding?

“…0.8 mm-thick clayey gouge (Figure 1). The assembly is then placed in the testing apparatus where one cylinder remains stationary while the other rotates [Mizoguchi et al, 2007b]. A Teflon ring surrounds the fault in order to avoid gouge expulsion during rotation.…”

Toward the Formulation of a Realistic Fault Governing Law in Dynamic Models of Earthquake Ruptures

“…In some cases (Bizzarri & Cocco, 2006b) it is impossible to determine the equivalent slip-weakening distance (in the sense Cocco & Bizzarri, 2002) and the friction exponentially decreases as recently suggested by several papers (Abercrombie & Rice, 2005;Mizoguchi et al, 2007). …”