Depth dependence of constitutive law parameters for shear failure of rock at local strong areas on faults in the seismogenic crust

作者：Ohnaka Mitiyasu^*; Kato Aitato

来源：Journal of Geophysical Research, 2007, 112(B7): B07201.

DOI：10.1029/2006JB004260

[1] In the framework of slip-dependent constitutive formulation, which leads to a unifying law that governs not only frictional slip failure at precut interface areas on faults but also shear fracture of intact rock at local strong areas on the faults, a thorough investigation has been made about how the constitutive law (of dimensionless form) for rock failure at local strong areas on faults is affected by seismogenic crustal conditions of effective normal stress, pore pressure, and temperature, on the basis of laboratory data on the shear fracture of granite rock obtained by Kato et al. (2003a) under crustal conditions simulated in the laboratory. It has been revealed how dimensionless constitutive law parameters distinctively vary with depth, depending on the crustal conditions simulated; consequently, the constitutive behavior including the slip-weakening phase also distinctively varies with depth. This behavior in the regime of suprahydrostatic pore pressure clearly differs from that in the regime of hydrostatic pore pressure. The results of this study are suited for implementation in a numerical code, and the constitutive properties of rock failure at local strong areas (called "asperites'') on faults will be easily assimilated into numerical models of earthquake ruptures for realistic computer simulation.

• 出版日期2007-7-6
• 单位中国科学院理论物理研究所