CHARACTERISTICS AND DISTRIBUTION OF STRONG GROUND MOTION DURING THE 2004 NIIGATA-KEN CHUETSU AND 2007 NIIGATA-KEN CHUETSU-OKI EARTHQUAKE IN JAPAN

摘要

Many houses and infrastructures were damaged during the 2004 Niigata-ken Chuetsu earthquake and the 2007 Niigata-ken Chuetsu-Oki earthquake in Japan. Distribution of peak ground motion is estimated in order to discuss the relation between the ground motion and damage grade. AVS30 in every 250x250m area is estimated by combining geomorphologic classification and borehole data. Distributions of seismic indices, peak ground velocity and JMA instrumental seismic intensity for the 2004 and 2007 earthquakes are estimated by the spatial interpolation based on Kriging method from the observed records. Non-linear amplification factor of surface soil is used in the estimation. The estimated distributions of strong ground motion are consistent with the damaged area and the liquefied area during the earthquakes.