Supercycle of giant earthquakes around Japan and tsunami forecast

2016 Fiscal Year Final Research Report

• Project/Area Number: 24241060
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Natural disaster science
• Research Institution: The University of Tokyo
• Principal Investigator: SATAKE Kenji 東京大学, 地震研究所, 教授 (20178685)
• Co-Investigator(Kenkyū-buntansha): 谷岡 勇市郎 北海道大学, 理学研究院, 教授 (40354526)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 巨大地震 / 津波 / 沈み込み帯

Outline of Final Research Achievements

The 2011 Tohoku earthquake consisted of ruptures on deeper plate interface and shallower slip near trench axis. By using this model of the 2011 earthquake, sizes of the 869 Jogan earthquake along Japan Trench and the 17th century earthquake along Kuril Trench which brought tsunami deposits on the Hokkaido coast were estimated as M 8.8 or larger. Tsunami deposits from older giant earthquakes along Japan and Kuril Trenches were also found in Hokkaido and Tohoku coasts. These support a supercycle model of giant earthquakes along Japan and Kuril Trenches, in which giant earthquakes of M~9 repeat with intervals of 400 to 600 years, in addition to recurrence of M~8 earthquakes with intervals of several decades. We also proposed a real-time forecast method of tsunami inundation for such a giant earthquake.

Free Research Field

地震学