Springer International Publishing AG;Berlin/Heidelberg: Springer Berlin Heidelberg
摘要:
摘要： To understand the generation mechanism of the 2011 Tohoku-Oki earthquake, we analyzed the spatial and temporal distribution of the cumulative seismic moment (Σ M 0 ) for all earthquakes along the Japan Trench listed in the global centroid moment tensor catalog between January 1976 and November 2011. Three areas with distinct characteristics of Σ M 0 are identified: (1) in the 2011 Tohoku-Oki source area, the Σ M 0 released in the down-dip portion (≥30 km) was greater than that in the up-dip portion (<30 km) before the mainshock; (2) the Σ M 0 of the up-dip portion in the region where slow slip activity prevails is greater than that of the down-dip portion throughout the study period; (3) in the surroundings of the source area, where interplate coupling is relatively low and the largest foreshock occurred, values of Σ M 0 for the down-dip and up-dip portions are both intermediate. Our results show that a megathrust rupture could be generated by large accumulations of strain energy at the subduction interface, resulting from the differential strain energy released in the down-dip and up-dip portions during the interseismic interval. We propose that the variation pattern of Σ M 0 may offer spatial constraints for seismic hazard assessment in the future. 其他題名： Earth Planet Sp 出版者： Berlin/Heidelberg: Springer Berlin Heidelberg 出版日期： 2012-01-01 出處： Earth, planets, and space, 2012-01, Vol.64 (12), p.1067-1075 資源來源： Publicly available content database 版權： The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences; TERRAPUB. 2012 版權： The Society of Geomagnetism and Earth, Planetary and Space Sciences, The Seismological Society of Japan 2012 識別號： ISSN: 1343-8832 識別號： ISSN: 1880-5981 識別號： EISSN: 1880-5981 識別號： DOI: 10.5047/eps.2012.04.006
