Publication Date:
2011-02-19
Description:
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 (M(w)) 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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bouchon, Michel -- Karabulut, Hayrullah -- Aktar, Mustafa -- Ozalaybey, Serdar -- Schmittbuhl, Jean -- Bouin, Marie-Paule -- New York, N.Y. -- Science. 2011 Feb 18;331(6019):877-80. doi: 10.1126/science.1197341.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Centre National de la Recherche Scientifique and Universite Joseph Fourier, Grenoble, France. Michel.Bouchon@ujf-grenoble.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21330536" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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