Journal of Natural Disaster Science

Journal of Natural Disaster Science, Volume 1, Number 2, 1979, pp.11f.

BAYWATER RESPONSE TO THE TSUNAMI CAUSED BY THE OFF-MIYAGI EARTHQUAKE IN JUNE, 1978

Toshio IWASAKI
Professor, Tohoku University, Sendai
and
Tetsuo ABE
Assistant Professor, Tohoku Institute of Technology, Sendai

(Received 16 November, 1979, and in revised form 25 January, 1980)

Abstract

To investigate responses of baywaters to tsunamis, records of tsunami caused by the Off-Miyagi earthquake in June, 1978 were analysed on the basis of theories on stationary and non-stationary stochastic processes. In the first half of the tsunami, the forced and free oscillations were superimposed giving complicated spectra. In the second half, the frequency bands of the oscillation energy were transferred to the basic mode or to the secondary mode of oscillations based on the locality of bays.

Key words

baywater oscillation, tsunami, harbour oscillation, Off-Miyagi earthquake