Risk evaluation of earthquake-induced landslides in the Nepal Himalaya and its application to local disaster preparedness

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H03149
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Natural disaster / Disaster prevention science
• Research Institution: Hirosaki University
• Principal Investigator: Higaki Daisuke 弘前大学, 農学生命科学部, 教授 (10302019)
• Co-Investigator(Kenkyū-buntansha): 八木 浩司 山形大学, 地域教育文化学部, 教授 (40292403) ; 鄒 青穎 弘前大学, 農学生命科学部, 助教 (40750055)
• Research Collaborator: HAYASHI Kazunori ; AMATYA Shanmukesh Chandra
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ゴルカ地震 / ランドスライド / 表層崩壊 / 危険箇所評価 / 地形 / ヒマラヤ / ネパール

Outline of Final Research Achievements

Based on the geomorphological and geological distribution analysis of the landslides induced by the Nepal Gorkha Earthquake in 2015, a GIS-based landslide susceptibility mapping method is proposed. The 13,000 landslides dominated by shallow disrupted slides are identified. Intensive occurrences in the Gorkha, Trishili River and Bhotekoshi areas reveal that slope gradient, relative relief and ground openness to the sky are the important topographical factors of landslides. Weight of three factors and ranks in each is introduced by the buffer movement analysis and blunder analysis of these factors for the occurrences and non-occurrences of landslides. Since gradient of the slopes occupied by the landslides are different from those of houses and farmlands, the susceptibility mapping might be effective in land use planning for seismic hazard management.

Free Research Field

斜面防災

Academic Significance and Societal Importance of the Research Achievements

本研究は, 2015年ネパール大地震で多発した斜面崩壊発生箇所の地形・地質的分析から地震による崩壊危険箇所を把握する手法を提案したものである。研究成果は，ネパールの復興だけでなく, 東西方向に類似した地形・地質構造の山地に多数の人口を擁するヒマラヤ諸国の今後の地震災害の軽減に役立つ。同時に,類似の地質を持つ西南日本の南海トラフ地震想定被害域での斜面災害危険箇所予測にも役立つ。