ATTENUATION MODELS FOR RESPONSE SPECTRA DERIVED FROMJAPANESE STRONG-MOTION RECORDS ACCOUNTING FORTECTONIC SOURCE TYPES

摘要

A spectral acceleration attenuation model for Japan is presented. It accounts for effects of tectonic sourcetype and the faulting mechanisms for crustal earthquakes. Site class terms, instead of individual sitecorrection terms, are used based on a recent study on site classification for strong motion recordingstations in Japan. By using site class terms, source type effects are identified. For crustal and interfaceearthquakes, a simple form of attenuation model is able to capture the main strong motion characteristicsand achieve unbiased estimates. For subduction slab events, a simple distance modification factor isemployed to achieve plausible and unbiased prediction. Effects of source depth, tectonic source type, andfaulting mechanisms for crustal earthquakes are significant.