PREDICTABILITY TIME FROM THE SEISMIC SIGNAL IN AN EARTHQUAKE MODEL

We compute the maximum Lyapunov exponent lambda of an earthquake model which exhibits deterministic chaos and we discuss its relation with the predictability time of the system. A method is proposed to estimate lambda by the calculation of the entropy of Markov processes which mimic (i) a Poincare map of the model and (ii) a random map related to the seismic signal. The latter map can be obtained using experimental records generated by low-dimensional chaotic systems where Poincare maps are not feasible.