Precursory correlation dimensions for three great earthquakes

摘要

On 26 December 2004, the Great Sumatra earthquake of M-w = 9 rocked the Southeast Asian continent. Fractal analysis of earthquakes (m(b) >= 4) occurring during 1996-2005 led to the decrease of correlation dimension in the narrow time-span prior to the mainshock. Such precursors were also observed prior to the 17 August 1999 Izmith earthquake of M-s = 7.8 and the 3 November 2002 Dennali earthquake of M-s = 8.5. Spatio-temporal clustering apparently indicates a highly stressed region, an asperity or weak zone from where the rupture propagation eventually nucleates causing a large earthquake. The results are in conformity with similar analysis for a few earthquakes reported earlier in India and elsewhere.