For real-time estimation of earthquake damage, high-spatial resolution estimation of ground-motion spectra in wide area is required from relatively low-dense strong-motion observation information. In this paper, we propose a method to estimate distribution of response spectra, based on combination of spatial interpolation (kriging) on engineering/seismic bedrock and spectral modal analysis which takes into account soil non-linearity by equivalent linearization. The application examples in Sendai are also indicated using strong motion records during the recent disastrous earthquakes of 2005 and 2008.
