Centro de Documentacion de Fundación MAPFRE - Extended nucleation of the 1999 Mw 7.6 Izmit Earthquake

Notes: Sumario: Laboratory and theoretical studies suggest that earthquakes are preceded by a phase of developing slip instability in which the fault slips slowly before accelerating to dynamic rupture. We report here that one of the best-recorded large earthquakes to date, the 1999 moment magnitude (Mw) 7.6 Izmit (Turkey) earthquake, was preceded by a seismic signal of long duration that originated from the hypocenter. The signal consisted of a succession of repetitive seismic bursts, accelerating with time, and increased low-frequency seismic noise. These observations show that the earthquake was preceded for 44 minutes by a phase of slow slip occurring at the base of the brittle crust. This slip accelerated slowly initially, and then rapidly accelerated in the 2 minutes preceding the earthquake Related records: En: Science. - 18/03/2011; Vol. 331; p. 877-880Materia / lugar / evento: Catástrofes naturales Predicciones Sismicidad Terremotos Turquía Otros autores: Bouchon, Michel
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