2020 Fiscal Year Final Research Report
The current activities of the gravity faults in the Tateyama Caldera and the factors that bring about activities
Project/Area Number |
18K01130
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Review Section |
Basic Section 04010:Geography-related
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Research Institution | Tateyama Caldera Sabo Museum |
Principal Investigator |
FUKUI Kotaro 公益財団法人立山カルデラ砂防博物館, 学芸課, 学芸課長補佐 (10450165)
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Project Period (FY) |
2018-04-01 – 2021-03-31
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Keywords | 重力断層 / 立山カルデラ / 深層崩壊 / 室堂山 / 鬼界アカホヤ火山灰 / 放射性炭素年代 |
Outline of Final Research Achievements |
As a result of dGPS surveying, no horizontal displacement that clearly exceeds the error was observed in the measurement points around the gravity fault for about two years from September 2018 to October 2020. However, vertical displacement slightly exceeding the error was observed at five measurement points. This suggests that the gravity fault around Mt. Murodoyama may still be moving very slowly. We also collected sediment cores using a portable percussion coring system at two ponds in the bottom of depressions formed by the gravity fault. Sediment core analysis revealed for the first time that the formation age of the gravity faults around Mt. Murodoyama is in the early Holocene.
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Free Research Field |
地理学
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Academic Significance and Societal Importance of the Research Achievements |
重力断層は深層崩壊の予兆現象と考えられており、室堂山の重力断層が地震や豪雨で大きく動いて深層崩壊が発生した場合、立山カルデラ内を流れる湯川上流部で河道閉塞が起こり、過去に発生したような決壊洪水による災害を富山平野にもたらす可能性がある。本研究の結果、重力断層の現在の活動状況や形成年代といった今まで全く情報が無かった点について解明が進んだ。
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