On-off intermittency in mean-field earthquake modelE. Lippiello1, L. de Arcangelis2 and C. Godano3
1 Dipartimento di Scienze Fisiche, Università di Napoli "Federico II" 80125 Napoli, Italy
2 Dipartimento di Ingegneria dell'Informazione and CNISM Seconda Università di Napoli - 81031 Aversa (CE), Italy
3 Dipartimento di Scienze Ambientali and CNISM Seconda Università di Napoli - 81100 Caserta, Italy
received 13 July 2006; accepted in final form 13 October 2006
published online 8 November 2006
Earthquake occurrence is characterized by clustering of events leading to a complex time organization. A recent model, that introduces a memory effect within a Self-Organized Criticality (SOC) approach, was able to reproduce the statistical features in time and energy of seismic catalogs. We present a mean-field solution of this model which provides a quadratic equation similar to the logistic map for the event probability. By introducing a triggering threshold, we generate a sequence of events with a statistical organization depending on the control parameter . If is generated by the SOC with memory model, one finds on-off intermittency features, in good agreement with experimental analysis of the California catalog. Conversely, if is randomly chosen, the typical Poisson-like behaviour is observed. This result supports the idea that the on-off intermittent behaviour, experimentally observed, is related to a mechanism of event triggering driven by the history of seismic events.
89.75.-k - Complex systems.
05.45.-a - Nonlinear dynamics and chaos.
91.30.Dk - Seismicity.
© EDP Sciences 2006