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

• 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
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥12,090,000 (Direct Cost: ¥9,300,000、Indirect Cost: ¥2,790,000); Fiscal Year 2018: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000); Fiscal Year 2017: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2016: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
• 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 / 斜面崩壊 / 地形条件 / AHP / 崩壊分布図 / ハザードマップ / ネパールゴルカ地震 / ネパールヒマラヤ / 地震 / AHP法 / 傾斜 / 起伏量 / 地上開度 / 地すべり地形 / 崩壊 / 隆起 / 河川侵食 / 谷中谷 / 受け盤斜面 / 危険個所評価 / 復興

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.

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。

Research Products

• [Journal Article] Dormant landslides distributed in upper course of Sun Kosi Watershed and landslides induced by Nepal Gorkha Earthquake 2015 (2018)
  • Author(s): Yagi, H., Hayashi, K., Higaki, D., Tsou, C.Y., and G. Sato
  • Journal Title: Journal of Nepal Geological Society Volume: 55 Pages: 61-67
  • Peer Reviewed
• [Journal Article] Topographic characteristics of landslides induced by the 2015 Gorkha earthquake, Nepal. (2018)
  • Author(s): Tsou, C.Y., Higaki, D., Chigira, M., Yagi, H., Dangol, V., Amatya, S.C., Hayashi., K., Kato, H.,
  • Journal Title: Journal of Nepal Geological Society Volume: 55 Pages: 69-75
  • Peer Reviewed / Open Access
• [Journal Article] Dormant landslides distributed in upper course of Sun Kosi watershed and landslides induced by Nepal Gorkha Earthquake 2015. (2018)
  • Author(s): Yagi, H., Hayashi, K., Higaki, D., Tsou, C.Y. and Sato, G.
  • Journal Title: Journal of Nepal Geological Society Volume: 55(special issue) Pages: 1-7
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Topographic and geologic controles on landslides induced by the 2015 Gorkha earthquake and its aftershoks: an example from the Trishuli Valley, central Nepal. Landslides (2017)
  • Author(s): Tsuo, C-Y., Chigira, M., Higaki, D., Sato,G., YAGI, H., Sato,P.H., Wakai, A., Dangol, V., Amatya, S.C. and Yatagai, A.
  • Journal Title: Journal of the International Consortium on Landslides Volume: vol.0 Issue: 5 Pages: 1-13
  • DOI: 10.1007/s10346-017-0913-9
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] ネパール中部・小ヒマラヤ帯の河谷を埋積するように発達する高位段丘とその形成年代 (2019)
  • Author(s): 八木浩司・下岡順直・長友恒人・松四雄騎・檜垣大助
  • Organizer: 日本地理学会
• [Presentation] ネパールゴルカ地震による斜面崩壊発生場の地形・地質特性 (2018)
  • Author(s): 檜垣大助・加藤京樹・鄒青穎・林一成・八木浩司・千木良雅弘
  • Organizer: 砂防学会
• [Presentation] ネパールゴルカ地震による斜面崩壊発生場の地形・地質特性 (2018)
  • Author(s): 檜垣大助・加藤京樹・鄒青穎・林一成・八木浩司・千木良雅弘
  • Organizer: 砂防学会2018年度研究発表大会
• [Presentation] 2015年ゴルカ地震による斜面崩壊の発生場条件ーネパールゴルカ地域 (2018)
  • Author(s): 檜垣大助・加藤京樹・鄒青頴
  • Organizer: 2017年度京都大学防災研究所研究発表会
• [Presentation] 2015年ネパールゴルカ地震によるランドスライドの発生分布と地形的特性 (2017)
  • Author(s): 檜垣大助・鄒青穎・加藤京樹・八木浩司・林一成
  • Organizer: 2017年京都大学防災研究所研究発表会
• [Presentation] Dormant landslides distributed in upper course of Sun Kosi watershed and landslides induced by Nepal Gorkha Earthquake 2015. (2017)
  • Author(s): Yagi, H., Hayashi, K., Higaki, D., Tsou, C.Y. and Sato, G.
  • Organizer: The 11th Asian Regional Conference of IAEG、Kathmandu
• [Presentation] Distribution map of landslies triggered by the 2015 Gorkha Earthquake, Nepal. (2017)
  • Author(s): CY. Tsou, Chigira, M., Higaki, D., Yagi, H., Dangol, V., Amatya, S.C., Hayashi, K, and H.Kato
  • Organizer: The 11th Asian Regional Conference of IAEG
• [Book] K.Sassa et al, ed. Advancing Culture of Living with Landslides Vol.1 ISDR-ICL Sendai partnership 2015-2025 (2017)
  • Author(s): Higaki, D., Hamasaki, E. and K. Hayahi
  • Total Pages: 8
  • Publisher: Springer
  • ISBN: 9783319535005