2019 Volume 19 Issue 1 Pages 1_121-1_135
In prediction of seismic intensity distribution maps for scenario earthquake, several cases of source parameter settings are adopted in order to incorporate epistemic uncertainty associated with prediction results. In the previous study, the authors proposed a mode decomposition method to evaluate spatial variation and correlation reflected in a set of seismic intensity distribution maps by use of singular value decomposition technique. In this study, the proposed method was applied to four kinds of scenario earthquakes which can be potentailly caused by two kinds of reverse faults (Eastern Boundary Fault Zone of the Ishikari Lowland: 12 cases and Fukaya Fault Zone: 12 cases) and two kinds of left strike-slip faults (South Western segment of the Yamazaki Fault Zone, main part: four cases and Central North segment of Fault Zone of the Itoigawa-Shizuoka Tectonic Line: eight cases). Spatial variations derived as left-singular vectors in modal forms are visualized. Dominant factors, such as moment magnitude, spatial configuration of asperities and forward directivity effect, were listed for each mode with reference to source parameter settings and righ-singular vectors characterizing the seismic distribution of each case.
