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Multifractal Scaling of Thermally-Activated Rupture Processes

D. Sornette·G. Ouillon
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Abstract

We propose a ``multifractal stress activation'' model combining thermally activated rupture and long memory stress relaxation, which predicts that seismic decay rates after mainshocks follow the Omori law $\sim 1/t^p$ with exponents $p$ linearly increasing with the magnitude $M_L$ of the mainshock and the inverse temperature. We carefully test this prediction on earthquake sequences in the Southern California Earthquake catalog: we find power law relaxations of seismic sequences triggered by mainshocks with exponents $p$ increasing with the mainshock magnitude by approximately $0.1-0.15$ for each magnitude unit increase, from $p(M_L=3) \approx 0.6$ to $p(M_L=7) \approx 1.1$, in good agreement with the prediction of the multifractal model.

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BibTeXRIS

D. Sornette, G. Ouillon. 2004-07-12. Multifractal Scaling of Thermally-Activated Rupture Processes. https://doi.org/10.1103/physrevlett.94.038501

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