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Positive Feedback, Memory and the Predictability of Earthquakes

S. G. Sammis·D. Sornette
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Abstract

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.

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BibTeXRIS

S. G. Sammis, D. Sornette. 2001-07-06. Positive Feedback, Memory and the Predictability of Earthquakes. https://doi.org/10.1073/pnas.012580999

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