Abstract
In order to investigate seismic response of long period structures such as oil storage tanks in Tokyo bay area during the Tokai earthquage (M8), which will occur at about200 km southwest from Tokyo in the near future, we quantitatively predicted long-period (> 4 sec) ground motions of this area by a neq procedeure using 3D finite difference method. Pesults show that during the Tokai earthquake, the long-duration and long-period ground motions are excited by the deep sedimentary basin and the peak levels of response spectra are different between east side and west side of Tokyo Bay.