Dilatancy associated with fault slip produces a transient pore pressure drop which increases frictional strength. This effect is analysed in steadily propagating rupture model that includes weakening, slip-dependent dilation and fluid flow. shown to increase the stress intensity factor required propagate tip. With increasing speed, an undrained (strengthened) region develops near tip extends be...

In this paper, we explore properties of the Gray-Thornton model for particle size segregation in granular avalanches. The model equation is a single conservation law expressing conservation of mass under shear for the concentration of the smaller of two types of particle in a bidisperse mixture. Sharp interfaces across which the concentration jumps are shock wave solutions of the partial differ...

[1] Earthquake nucleation requires reduction of frictional strength = ( p) with slip or slip rate, where , n, and p are the friction coefficient, normal stress, and fluid pressure, respectively. For rate state at fixed ( p), instabilities can occur when d ss/dv < 0, where ss is the steady state friction and v is slip rate. Shear heating increases p and, if dilatancy and pore pressure diffusion ...