Abstract
　In this study, the discrete wavenumber / finite element ( DWFE ) method ( Olson, l982 ) and the fault dislocation theory were applied to the case of the Izu-Hanto-Toho-Oki earthquake (M = 6.7 ) of 1980. Ground motions were computed at the sites of Kawana and Takada near the source region. The displacement seismograms systhesized from the theoretical method were compared with the actual strong-motion records. We were able to reproduce the recorded waveforms, particularly of body waves and the first portion of surface waves, by the theoretical synthesis method with a realistic crustal structure. The best agreement between the observed and synthesized waveforms was obtained for relatively long-period components with periods of 0.5 - 6 sec. The acceleration response spectra calculated at the two stations gave a good estimate of those observed over the period range from 0.5 to about l0 sec.

【キーワード】：離散型波数有限要素法，断層震源モデル，l980年伊豆半島東方沖地震，理論地震動， パラメトリック・スタディ

*京都大学工学部
Faculty of Engineering, Kyoto Univ.