Comment on " Earthquake cycles and physica modeling of the process leading up to a large earthquake

Abstract

The modeling of earthquake initiation and subsequent rupture propagation requires the use of a fault constitutive law controlling the traction evolution and the slip acceleration that yields a finite energy flux at the crack tip. The determination of the temporal evolution of dynamic traction during the propagation of an earthquake rupture has been the major task of many recent investigations. Ohnaka (2004) presented a detailed discussion in favor of a rational governing law for earthquake ruptures which is consistent with laboratory experiments and, according to the author, is based on the physics of rock friction and fracture . He concluded that this constitutive law must be slip-dependent, because the slip dependency is a more fundamental property of the shear rupture than the rate-dependency . Ohnaka (2004) suggested this slip-dependent law also to model the whole seismic cycle (therefore including earthquake nucleation and long-term fault re-strengthening) and considered the proposed law as a governing relation unifying the different features of the earthquake failure process.