Antipersistent dynamics in short time scale variability of self-potential signals

V. Cuomo, M. Lanfredi, V. Lapenna, M. Macchiato, M. Ragosta, L. Telesca

Abstract


Time scale properties of self-potential signals are investigated through the analysis of the second order structure function (variogram), a powerful tool to investigate the spatial and temporal variability of observational data. In this work we analyse two sequences of self-potential values measured by means of a geophysical monitoring array located in a seismically active area of Southern Italy. The range of scales investigated goes from a few minutes to several days. It is shown that signal fluctuations are characterised by two time scale ranges in which self-potential variability appears to follow slightly different dynamical behaviours. Results point to the presence of fractal, non stationary features expressing a long term correlation with scaling coefficients which are the clue of stabilising mechanisms. In the scale ranges in which the series show scale invariant behaviour, self-potentials evolve like fractional Brownian motions with anticorrelated increments typical of processes regulated by negative feedback mechanisms (antipersistence). On scales below about 6 h the strength of such an antipersistence appears to be slightly greater than that observed on larger time scales where the fluctuations are less efficiently stabilised.

Keywords


Fractal propeties;variogram analysis;antipersistence;self-potential signal;earthquake prediction

Full Text:

PDF

References


DOI: https://doi.org/10.4401/ag-3644
We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it (Read more).
Ok


Published by INGV, Istituto Nazionale di Geofisica e Vulcanologia - ISSN: 2037-416X