STRONGLY INTERMITTENT CHAOS AND SCALING IN AN EARTHQUAKE MODEL

We discuss the relation between scaling laws and dynamical behavior for earthquakes in the framework of a Burridge-Knopoff model. Due to the nontrivial interaction among many degrees of freedom, a new type of strongly intermittent chaos is found. The dynamics is dominated by wild fluctuations, implying exponential tails in the probability distributions. This is caused by very slow relaxation of time correlations, which gives rise to an anomalous behavior for the effective Lyapunov exponent and for the time signal of the earthquake magnitude