HR: 11:20h
AN: S32B-05    [Abstracts]
TI: Aseismic Slips Preceding Ruptures Assumed for Anomalous Seismicities and Crustal Deformations
AU: * Ogata, Y
EM: ogata@ism.ac.jp
AF: Institute of Statistical Mathematics, Research Organization of Information and Systems, Minami-Azabu 4-6-7, Minato-Ku, Tokyo, 104-8569, Japan
AU: * Ogata, Y
EM: ogata@ism.ac.jp
AF: Department of Statistical Science, Graduate University of Advanced Studies, Minami-Azabu 4-6-7, Minato-Ku, Tokyo, 104-8569, Japan
AB: If aseismic slips occurs on a fault or its deeper extension, both seismicity and geodetic records around the source should be affected. Such anomalies are revealed to have occurred during the last several years leading up to the October 2004 Chuetsu Earthquake of M6.8, the March 2007 Noto Peninsula Earthquake of M6.9, and the July 2007 Chuetsu-Oki Earthquake of M6.8, which occurred successively in the near-field, central Japan. Seismic zones of negative and positive increments of the Coulomb failure stress, assuming such slips, show seismic quiescence and activation, respectively, relative to the predicted rate by the ETAS model. These are further supported by transient crustal movement around the source preceding the rupture. Namely, time series of the baseline distance records between a numbers of the permanent GPS stations deviated from the predicted trend, with the trend of different slope that is basically consistent with the horizontal displacements of the stations due to the assumed slips. References Ogata, Y. (2007) Seismicity and geodetic anomalies in a wide area preceding the Niigata-Ken-Chuetsu Earthquake of October 23, 2004, central Japan, J. Geophys. Res. 112, in press.
UR: http://www.ism.ac.jp/~ogata/Ssg/ssgE.html
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 7215 Earthquake source observations (1240)
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 8164 Stresses: crust and lithosphere
SC: Seismology [S]
MN: 2007 Fall Meeting