日本海中部地震津波による災害について*

Abstract

On May 26, 1983, a great earthquake by which huge tsunamis were taken place occurred offNoshiro, Akita Prefecture in the Japan Sea. The tsunamis resulted in disasters along the coastalareas of the Japan Sea. Hundred persons were killed by the tsunamis, the breakwaters in NoshiroHarbour which are under construction were partially broken, and disasters of fishing boats were alsotaken place in many fishery harbours.A research group for studying this disasters was organized by the Japanese Group for the Studyof Natural Disaster Science to which a Grant-in-Aid in Natural Disasters has been given by theMinistry of Education, Science and Culture of Japan so that the authors' group surveyed disastersin the coastal areas between Toyama and Shimane Prefectures. In this report, some characteristicsof the tsunamis such as their spectra, propagation around the Japan Sea and deformation on shelfand around isands are first investigated both by numerical simulations of tsunami propagation andspectral analysis of tidal records. Disasters in the areas and energy concentration of the tsunamisare secondly studied in relation to the announcement of necessary refuge warning which was takenat the disasters.