[S-VC51] [JJ] 1986伊豆大島噴火を読み直す、温故知新

[SVC51-01] Reconsiderations on 1986-IzuOhshima eruption,Introduction

*栗田 敬¹、渡辺 秀文² (1.東京大学地震研究所、2.東京都総務局総合防災部)

キーワード：火山噴火、噴火予測、火山島

1986 Izu-Ohshima eruption has revealed several significant problems, which disclosed unmatured state of volcanology at that moment. The most significant situation was that the eruption style as well as the eruption site shifted with time during the course of eruption episodes. The volcanologists were faced the social demands for immediate response towards the transient behavior. This eruption may be the first occasion where the volcanologists deeply recognized the importance of real-time monitoring of the eruption activity. Why the eruption sequence changed? How did the observations trace the shift and how was the prediction of the shift possible?, these problems are still unanswered today. In this 100 years izu-Ohshima erupted repeatedly with the interval of 30-40 years.Already 30 years have passed since last eruption so that we could consider the next eruption.
In this session we will focus the following subjects,
1.Reconsideration on the unanswered problems of the eruption
2.Reconsideration on the eruption based on the current knowledge and technique
3.Propositions and proposals about future expected eruption
This presentation will summarize the session and try to show the possible orientation.