A number of observations indicate that an upper stability transition occurs along well-developed faults, such as the San Andreas, as a result of unconsolidated gouge within shallow regions of these faults. These observations include the depth distribution of seismicity along faults with and without well-developed gouge zones, correlations between seismicity and shallow crustal structure, and mo...

Microscale fluid dynamics has received intensive interest due to the emergence of microelectromechanical systems technology. When the mean free path of the gas is comparable to the channel’s characteristic dimension, the continuum assumption is no longer valid and velocity slip and temperature jump may occur at the duct walls. Slip flow heat transfer in annular microchannels has been examined. ...

Abundant geological, seismological and experimental evidence of the heterogeneous structure of natural faults motivates the theoretical and computational study of the mechanical behavior of heterogeneous frictional interfaces. Fault zones are composed of a mixture of materials with contrasting strength, which may affect the spatial variability of seismic coupling, the location of high-frequency...

We consider the effect of permanent stress changes on a velocity strengthening rate-and-state fault, through numerical simulations and analytical results on 1D, 2D and 3D models. We show that slip transients can be triggered by perturbations of size roughly larger than Lb = Gdc/bσ, where G is the shear modulus, dc and b are respectively the characteristic slip distance and the coefficient of th...

By integrating eeects of microscopic interactions between statisticaly self-similar fault surfaces, we succeeded in deriving a slip-and time-dependent fault constitutive law that rationally uniies the slip-dependent law and the rate-and state-dependent law (Aochi and Matsu'ura, 199881]). In this con-stitutive law the slip-weakening results from the abrasion of surface asperities that proceeds i...

We discuss the stick-slip motion of an elastic block sliding along a rigid substrate. We argue that for a given external shear stress this system shows a discontinuous nonequilibrium transition from a uniform stick state to uniform sliding at some critical stress which is nothing but the Griffith threshold for crack propagation. An inhomogeneous mode of sliding occurs when the driving velocity ...

The problem of a steady-state slip pulse of (nite size between dissimilar materials is studied. It is shown that for a Coulomb friction law, there is a continuous set of possible solutions for any slip propagation velocity and any slip length. These solutions are, however, nonphysical because they show a singular behaviour of the slip velocity at one extremity of the pulse, which implies a crac...

Physisorbed surfactant can change the hydrodynamic boundary condition of oil flow from “stick” to “partial slip”, provided that the shear stress on the wall exceeds a threshold level that decreases with increasing surface coverage of surfactant. To demonstrate this, Newtonian alkane fluids (octane, dodecane, tetradecane) were placed between molecularly smooth surfaces that were either wetting (...

Recent studies of strong motion data consistently show that the risetime (duration of slip at particular locations on the fault) is significantly shorter than the overall rupture duration. The physical explanation for this observation and its implications have become central issues in earthquake source studies. Two classes of mechanisms have been proposed to explain short risetimes. One explana...

The objective of the present study was to evaluate if anterior load carriage would increase the likelihood of slips or falls while walking over a slippery floor surface. The study hypothesized that anterior load carriage may alter spatial-temporal characteristics, such as heel contact velocity, walking velocity (i.e., the whole body center-of-mass velocity), and step length, as well as friction...