Paleotsunami research at small islands for better estimating tsunami source model

2016 Fiscal Year Final Research Report

• Project/Area Number: 26302007
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 海外学術
• Research Field: Geology
• Research Institution: Tohoku University
• Principal Investigator: Goto Kazuhisa 東北大学, 災害科学国際研究所, 准教授 (10376543)
• Co-Investigator(Kenkyū-buntansha): 菅原 大助 ふじのくに地球環境史ミュージアム, その他の部局等, 准教授 (50436078) ; 中村 教博 東北大学, 高度教養教育・学生支援機構, 教授 (80302248)
• Research Collaborator: Goff James ; Chague-Goff Catherine
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 津波堆積物 / 津波 / 島嶼 / 波源

Outline of Final Research Achievements

This study investigated geological evidence of paleotsunami at the islands near mainland of Japan, New Zealand, and United Sates of America. At Hachijo Island in Japan, we found numerous boulders on top of the 5 meter high cliff. Water tank experiment and numerical modeling revealed that these boulders can be explained by high storm wave although tsunamis with shorter wave period can also move these boulders. At Chatham Island in New Zealand, we identified boulders and sand to gravel sheet were deposited together. Field evidence as well as numerical modeling results may imply that these geological evidences could be explained by trans-Pacific tsunamis such as generated along Peru-Chile Trench, although further detail modeling is required. In Hawaii Islands, we identified possible evidence of 1946 Aleutian tsunami. These evidence would be useful to constraint the source model of this tsunami event.

Free Research Field

地質学