Positive Feedback, Memory and the Predictability of Earthquakes

S. G. Sammis , D. Sornette (1)

1 LPMC - Laboratoire de physique de la matière condensée

We review the "critical point" concept for large earthquakes and enlarge it in the framework of so-called "finite-time singularities". The singular behavior associated with accelerated seismic release is shown to result from a positive feedback of the seismic activity on its release rate. The most important mechanisms for such positive feedback are presented. We introduce and solve analytically a novel simple model of geometrical positive feedback in which the stress shadow cast by the last large earthquake is progressively fragmented by the increasing tectonic stress. Finally, we present a somewhat speculative figure that tends to support a mechanism based on the decay of stress shadows. This figure suggests that a large earthquake in Southern California of size similar to the 1812 great event is maturing.

Domaines: Autre [cond-mat.other]

S. G. Sammis, D. Sornette. Positive Feedback, Memory and the Predictability of Earthquakes. Proceedings of the National Academy of Sciences of the United States of America, 2002, 99, pp.2501-2508. ⟨hal-00111209⟩