Turbulencelike behavior of seismic time series.

Department of Physics, Sharif University of Technology, Tehran 11155-9161, Iran.
Physical Review Letters (Impact Factor: 7.73). 02/2009; 102(1):014101. DOI: 10.1103/PhysRevLett.102.014101
Source: PubMed

ABSTRACT We report on a stochastic analysis of Earth's vertical velocity time series by using methods originally developed for complex hierarchical systems and, in particular, for turbulent flows. Analysis of the fluctuations of the detrended increments of the series reveals a pronounced transition in their probability density function from Gaussian to non-Gaussian. The transition occurs 5-10 hours prior to a moderate or large earthquake, hence representing a new and reliable precursor for detecting such earthquakes.

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