Accelerating energy release prior to large events in simu- lated earthquake cycles: implications for earthquake fore- casting

Long earthquake sequences are generated using the 2D physically based lattice solid numerical model in a system representing an evolving fracture zone of the Earth's crust subjected to shear. Cycles of seismic activity are observed in which the rate of seismic energy release of simulated earthquakes accelerates in the lead-up to the largest events. During a cycle, the cumulative number of events with energy above a given value is well described by a Gutenburg-Richter power law frequency-size distribution with an exponent similar to earthquake data. The exponent is initially high and becomes low in the latter part of the cycle prior to when the large earthquakes occur. These results indicate that under certain conditions such as those comparable to the model system, earthquake statistics evolve in a predictable way. At least under such conditions, earthquake hazard forecasting would be viable.