Relation between deep low-frequency earthquakes and magmatic fluid

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K03816
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17040:Solid earth sciences-related
• Research Institution: The University of Tokyo (2021); Hot Springs Research Institute of Kanagawa Prefecture (2018-2020)
• Principal Investigator: Yukutake Yohei 東京大学, 地震研究所, 准教授 (20435853)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 深部低周波地震 / マグマ供給 / 火山活動

Outline of Final Research Achievements

Deep low-frequency earthquakes are seismic activities occurring at deep parts of volcanoes and only phenomena exciting at the depth. Therefore, this seismic activity provides us important data for understanding magma supply processes. In this research project, we estimated a comprehensive seismic catalog of deep low-frequency earthquakes and estimated the detailed crustal structure beneath Hakone volcano and found that deep low-frequency earthquakes are often temporally linked with shallow volcanic activities. The results also indicate that magma supply to deep volcanoes plays an important role in their activation.

Free Research Field

火山地震学

Academic Significance and Societal Importance of the Research Achievements

本研究を通して、火山深部低周波地震の活発化が火山深部へのマグマ供給レートの増加を反映し、多くの場合において火山浅部での群発地震活動や噴火に先行して起きることが明らかになった。深部低周波地震のリアルタイムでのモニタリングを通して、火山活発化への中期から短期的な予測につながる情報が得られ、今後の火山防災に対する重要な成果が得られた。