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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS009 Poster presentation 2045
New aspects on the statistical properties of seismicity
Prof. Panayiotis Varotsos
Physics Department University of Athens IASPEI
Efthimios S Skordas, Haruo Tanaka, Nicholas V Sarlis
We report a similarity of fluctuations in equilibrium critical phenomena and nonequilibrium systems[P.
Varotsos, N. Sarlis, H.Tanaka and E. Skordas, Phys. Rev. E 72, 041103 (2005)], which is based on the
concept of natural time [P. Varotsos, N. Sarlis and E. Skordas, Practica of Athens Academy 76, 294
(2001); ibid Phys. Rev. E 66, 011902 (2002)]. The worldwide seismicity as well as that of the San
Andreas fault system and Japan are analyzed. An order parameter is chosen and its fluctuations relative
to the standard deviation of the distribution are studied. We find that the scaled distributions fall on the
same curve, which interestingly exhibits, over four orders of magnitude, features similar to those in
several equilibrium critical phenomena, e.g., two-dimensional Ising model, as well as in nonequilibrium
systems, e.g., three-dimensional turbulent flow. Furthermore, it is explained, from first Principles, why
in the Gutenberg-Richter law the so called b-value is usually found to be around unity varying only
slightly from region to region. The explanation is achieved just by applying the analysis in the natural
time domain, without using any adjustable parameter [P. Varotsos, N. Sarlis, E. Skordas and H.Tanaka,
Proc. Jpn. Acad. Ser.B 80, 429 (2004); P. Varotsos, N. Sarlis, E. Skordas, H.Tanaka and M. Lazaridou,
Phys. Rev. E 74, 021123 (2006)].
Keywords: seismicity, gutenberg richter law, non equilibrium systems