Europhys. Lett.
Volume 76, Number 5, December 2006
Page(s) 979 - 985
Section Interdisciplinary physics and related areas of science and technology
Published online 08 November 2006
Europhys. Lett., 76 (5), pp. 979-985 (2006)
DOI: 10.1209/epl/i2006-10365-4

On-off intermittency in mean-field earthquake model

E. 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 $\alpha$. If $\alpha$ 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 $\alpha$ 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