SITE AMPLIFICATION FACTOR ESTIMATED WITH SUPER-DENSE ARRAY OBSERVATION IN CAPITAL REGION

Abstract

 Many earthquake records are observed by the super-dense realtime monitoring system, SUPREME, by Tokyo Gas Co., Ltd. Amplification factors are estimated for over 3, 000 sites using observed recors for about ten years. Observed SI values were gathered for the five minutes and the distribution map of SI values with 50m-meshes were calculated after ten minutes at the 2011 off the Pacific coast of Tohoku earthquake. Average amplification factors of SI values at observation sites are estimated by attenuation curves of observed earthquekes with K-NET records. Those show to be well correlated to average S-wave velocity in the upper 20m (AVS20) and geomorphologic classification.