HR: 1340h
AN: S23A-0292    [Abstracts]
TI: Correlation Length as an Indicator of Critical Point Behavior Prior to a Large Earthquake
AU: Tyupkin, Y
EM: tyupkin@wdcb.ru
AF: Geophysical Center, RAS, Molodezhnaya 3, Moscow, 117296 Russian Federation
AU: * Di Giovambattista, R
EM: digiovam@ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Rome, 00143 Italy
AB: A large earthquake preparation is often manifested in correlation of seismicity in an area whose characteristic dimension greatly exceeds a dimension of source of main shock. Zoller et al. (2001) show the growth of correlation length of earthquakes prior to nine large earthquakes in California according to a power low. We argue that the algorithm of correlation length estimation proposed by Z”ller et al.(2001) can result in a decrease of correlation length preceding its precursory growth before large earthquakes if the area in which earthquake activity is correlated grows with time during a main shock preparation. The correlation length analysis of acoustic emission events recorded in laboratory experiments on destruction of rocks and correlation length analysis of intermediate magnitude earthquakes in the area of large earthquakes preparation on Kamchatka and in Italy confirms the theoretical argument. This effect can be considered as an additional premonitory pattern of large earthquake preparation.
DE: 7223 Seismic hazard assessment and prediction
DE: 7230 Seismicity and seismotectonics
DE: 7209 Earthquake dynamics and mechanics
SC: Seismology [S]
MN: 2004 AGU Fall Meeting