Risk evaluation of coastal erosin caused by Nankai megathrust earthquakes

• Project/Area Number: 25750148
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Natural disaster / Disaster prevention science
• Research Institution: The University of Tokyo (2015); Chiba University (2013-2014)
• Principal Investigator: Obanawa Hiroyuki 東京大学, 工学(系)研究科(研究院), 特任研究員 (10422205)
• Research Collaborator: HAYAKAWA YUICHI 東京大学, 空間情報科学研究センター, 准教授 (70549443)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2015: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: 海岸侵食 / 地盤沈下 / 南海トラフ / 地震 / 南海トラフ巨大地震 / リスク評価

Outline of Final Research Achievements

Risk evaluation of coastal erosion caused by Nankai megathrust earthquake was carried out. Based on the historical records remarkable and cyclic land subsidence caused by mega earthquake occurred at Kochi coast up to 2 m and Shichiriohama up to 40 cm therefore those two areas were chosen for the study areas of this study. Calculation result with an existing equation for coastal erosion showed that 81 to 135 m erosion will occur at Kochi coast and 2 to 21 m erosion will occur at Shichiriohama after the mega earthquake. At Kochi coast 21% of the eroded area is building region and 11% of that is farm land where are residential and economic areas so direct damage by the coastal erosion will be relatively large. On the other hand at Shichiriohama large part (37%) of the eroded area is in the beach so the disaster damage will be relatively small.

Research Products

• [Journal Article] SfM多視点ステレオ写真測量の地形学的応用 (2016)
  • Author(s): 早川裕弌, 小花和宏之, 齋藤 仁, 内山庄一郎
  • Journal Title: 地形 Volume: TBD
  • NAID: 40020921321
  • Peer Reviewed
• [Journal Article] サンゴ礁海域を対象としたSfMによる水中3次元計測の可能性 (2016)
  • Author(s): 村上智一・小花和宏之・河野裕美・下川信也・田林 雄・水谷 晃
  • Journal Title: 海洋開発論文集 Volume: TBD
  • NAID: 130005263290
  • Peer Reviewed
• [Journal Article] 小型UAVによる空撮とSfMを用いた樹高計測 (2015)
  • Author(s): 田村太壱, 加藤 顕, 小花和宏之, 吉田俊也
  • Journal Title: 日本緑化工学会誌 Volume: 41 Pages: 163-168
  • NAID: 130005147614
  • Peer Reviewed / Open Access
• [Journal Article] A study of Japanese landscapes using structure from motion derived DSMs and DEMs based on historical aerial photographs: New opportunities for vegetation monitoring (2015)
  • Author(s): Gomez, C., Hayakawa, Y.S., and Obanawa, H.
  • Journal Title: Geomorphology Volume: TBD Pages: 11-20
  • DOI: 10.1016/j.geomorph.2015.02.021
  • Peer Reviewed / Open Access
• [Journal Article] 小型無人航空機および単独測位GNSS搭載カメラを用いた簡易的な地形測量手法 (2015)
  • Author(s): 小花和宏之, 早川裕弌, 加藤 顕, ゴメス クリストファー
  • Journal Title: 地形 Volume: 35 Pages: 1-20
  • NAID: 40020476525
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] 自力で航空測量 (2014)
  • Author(s): 小花和宏之
  • Journal Title: GIS NEXT Volume: 46 Pages: 88-89
• [Journal Article] UAV-SfM手法と地上レーザ測量により得られたDSMの比較 (2014)
  • Author(s): 小花和宏之・早川裕弌・齋藤 仁・ゴメス クリストファー
  • Journal Title: 写真測量とリモートセンシング Volume: 53(2)
  • NAID: 130005067176
  • Peer Reviewed
• [Journal Article] UAV空撮とSfMを用いたアクセス困難地の3Dモデリング (2014)
  • Author(s): 小花和宏之・早川裕弌・ゴメス クリストファー
  • Journal Title: 地形 Volume: 35(3)
  • NAID: 110009833192
  • Peer Reviewed
• [Journal Article] 南九十九里海岸の汀線変化に対する地盤沈下の影響評価：海浜土砂収支に基づく検討 (2013)
  • Author(s): 小花和宏之・徳永朋祥
  • Journal Title: 沿岸域学会誌 Volume: 26(3) Pages: 153-165
  • NAID: 40019959547
  • Peer Reviewed
• [Presentation] Geomorphology and archaeology: mapping landforms around archaeological sites in Kayseri region using high-definition data (2015)
  • Author(s): Hayakawa, Y.S., Obanawa, H., Yoshida, H., Naruhashi, R., Okumura, K. and Zaiki, M.
  • Organizer: International Geographical Union Regional Conference 2015 (IGU2015)
  • Place of Presentation: Moscow Russia
  • Year and Date: 2015-08-17
  • Int'l Joint Research
• [Presentation] High resolution and frequency measurement of erosion volume of inaccessible sea cliff using Unmanned Aerial Vehicle (2015)
  • Author(s): Obanawa, H. and Hayakawa, Y.S.
  • Organizer: International Geographical Union Regional Conference 2015 (IGU2015)
  • Place of Presentation: Moscow Russia
  • Year and Date: 2015-08-17
  • Int'l Joint Research
• [Presentation] Fusion between UAV-SfM and terrestrial laser scanner for field validation of satellite remote sensing (2015)
  • Author(s): Kato, A., Obanawa, H., Hayakawa, Y.S., Watanabe, M., Yamaguchi, Y. and Enoki, T.
  • Organizer: International Geoscience and Remote Sensing Symposium 2015 (IGARSS 2015)
  • Place of Presentation: Milan Italy
  • Year and Date: 2015-07-26
  • Int'l Joint Research
• [Presentation] Quantitative measurement of the topographic change at overhanging sea cliff with small UAV survey system (2015)
  • Author(s): Obanawa, H.
  • Organizer: International Geoscience and Remote Sensing Symposium 2015 (IGARSS 2015)
  • Place of Presentation: Milan Italy
  • Year and Date: 2015-07-26
  • Int'l Joint Research
• [Presentation] Mapping surface morphology and outcrop structures of hummocks in debris avalanche deposits using structure-from motion multi-view stereo photogrammetry (2015)
  • Author(s): Hayakawa, Y.S., Obanawa, H., Yoshida, H., Naruhashi, R., Okumura, K., Zaiki, M. and Kontani, R.
  • Organizer: International Union for Quaternary Science (INQUA) 2015
  • Place of Presentation: Nagoya
  • Year and Date: 2015-07-26
  • Int'l Joint Research
• [Presentation] アクセス困難な海食崖における高解像度かつ高頻度な地形変化計測手法 (2015)
  • Author(s): 小花和宏之, 早川裕弌
  • Organizer: 日本地球惑星科学連合2015年大会
  • Place of Presentation: Chiba
  • Year and Date: 2015-05-24
  • Int'l Joint Research / Invited
• [Presentation] Detection of morphological changes in cliff face surrounding a waterfall using terrestrial laser scanning and unmanned aerial system (2015)
  • Author(s): Hayakawa, Y.S. and Obanawa, H.
  • Organizer: European Geosciences Union General Assembly 2015
  • Place of Presentation: Vienna Austria
  • Year and Date: 2015-04-12
  • Int'l Joint Research
• [Presentation] High-resolutional topographic survey using small UAV and SfM-MVS technologies in hardly accessible area (2015)
  • Author(s): Obanawa, H. and Hayakawa, Y.S.
  • Organizer: The International Symposium on Cartography in Internet and Ubiquitous Environments 2015
  • Place of Presentation: Tokyo University
  • Year and Date: 2015-03-18
• [Presentation] Mapping cliff face changes around a waterfall using terrestrial laser scanning and UAS-based SfM-MVS photogrammetry (2015)
  • Author(s): Hayakawa, Y.S. and Obanawa, H.
  • Organizer: The International Symposium on Cartography in Internet and Ubiquitous Environments 2015
  • Place of Presentation: Tokyo University
  • Year and Date: 2015-03-18
• [Presentation] Structure from Motion for pointclouds creation from historical imagery and UAV: Monitoring floodplain vegetation evolution in 3D (2014)
  • Author(s): Gomez, C. Obanawa, H., Kato, A., Hayakawa, Y.S. and Saito, H.
  • Organizer: 5th Digital Earth Summit 2014
  • Place of Presentation: WINC AICHI
  • Year and Date: 2014-11-09 – 2014-11-11
• [Presentation] Morphological analysis of an uplifted coastal terrace using high definition topographic data: possible erosion by high waves of tsunamis (2014)
  • Author(s): Hayakawa, Y.S., Obanawa, H., Wassmer, P., Oguchi, T. and Saito, H.
  • Organizer: Geological Society of America 2014
  • Place of Presentation: Vancouver Canada
  • Year and Date: 2014-10-19
• [Presentation] 3D Modelling of Inaccessible Areas using UAV-based Aerial Photography and Structure from Motion (2014)
  • Author(s): Hiroyuki Obanawa, Yuichi Hayakawa and Christopher Gomez
  • Organizer: European Geosciences Union General Assembly 2014
  • Place of Presentation: Vienna, Austria
• [Presentation] 小型UAV航空測量結果の精度検証 (2014)
  • Author(s): 小花和宏之・早川裕弌
  • Organizer: 日本写真測量学会平成26年度年次学術講演会
  • Place of Presentation: 東京大学生産技術研究所
• [Presentation] 低コストな空撮・地形測量システムの開発 (2013)
  • Author(s): 小花和宏之
  • Organizer: 第5回GIS-Landslide研究集会
  • Place of Presentation: 防災科学技術研究所