Dynamics and scaling characteristics of shear crack propagation

A model for a description of a shear crack (fault) propagation is proposed on the basis of the unification of continuum damage and fracture mechanics with ideas of Fracture models for random media. Energy release linked with local failures of elements as a result of evolution of fracture processes a t lower scale levels (stimulated by the stress concentration in the vicinit y of the fault) is treated as a seismicity source. 2d simulations are perfo rmed for analysis of the effect of the size of pre-existing fault on charac teristic features of rupture evolution. Scaling (including multifractal) ch aracter of crack propagation and of respective energy release is shown.