Sedimentological verifications on the depositional process by the large waves on the coastal area.

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 16540423
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geology
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: NANAYAMA Futoshi National Institute of Advanced Industrial Science and Technology, Institute of Geology and Geoinformation, Senior Researcher, 地質情報研究部門, 主任研究員 (20357685)
• Project Period (FY): 2004 – 2006
• Keywords: Tsunami / Tsunami deposit / Great earthquake / Sedimentation / Sedimentary structure / Typhoon and hurricane / Kuril trench / Hydoric experiment

Research Abstract

We summarized the science results of our research program during 2004-2006 as bellow.
(1)Based on modern tsunami sedimentation, such as the 1993 Hokkaido naisei-oki tsunami, 2003 Tokachi-oki tsunami and 2006 Java tsunami, we described typical sedimentary structures and sedimentary process by large tsunami waves.
(2)Twenty-two postulated tsunami deposits in the Holocene sediments cored from Lake Harutori-ko at Kushiro were already described by sedimentary methods and AMS^<14>C and tephrochronology dating. As a result of our study, we identified drastic changes of the diatom assemblages in this core. We infer that these changes were generated by repeated great earthquakes (M8.5) associated with large tsunamis along the Kuril subduction zone.
(3)The stratigraphic lacustrine cores of Lake Tokotan-numa at Akkeshi provides evidence for unusually prehistorical tsunamis and historical to modern tsunamis during the late Holocene. Especially, we found a historical tsunami deposits between Ko-c1 (1856) tephra from Komagatake and Ta-a (1739) tephra from Tarumai. We consider that this historical event can be contrasted with the 1843 Tenpo tsunami, which described in the old document Nikkanki of the Kokutai-ji temple at Akkeshi.
(4)According to our stratigraphic methods such as tephrochronology and AMS^<14>C dating, we identified twelve tsunami deposits in marsh deposits in Nemuro lowland area. In fact, these traces involve more layers than other large tsunami traces extending between Tokachi coast and Kiritappu marsh. In these facts, It has been concluded that it is necessary to estimate other tsunami sources off southern part of Kuril islands as well, other than tsunami sources caused by multi-segment of inter-plate earthquake such as off Tokachi and Nemuro areas.
(5)We tried presumptive hydraulic experiments in order to clarify the relationship between hydrodynamic characteristics and depositional process by tsunami waves.

Research Products

• [Journal Article] Unusually nine large tsunami deposits from the past 4000 years at Kiritappu marsh along the southern Kuril Trench (2007)
  • Author(s): Nanayama, F., 他5名
  • Journal Title: Sedimentary Geology (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Inflow and outflow facies from the 1993 tsunami in southwest Hokkaido (2006)
  • Author(s): Nanayama, F., Shigeno, K.
  • Journal Title: Sedimentary Geology 187 Pages: 139-158
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] 平成15年9月26日十勝沖地震津波によって生じた土砂移動現象-被災直後の堆積学的記載の重要性- (2006)
  • Author(s): 七山 太, 他3名
  • Journal Title: 地質ニュース 620 Pages: 10-18
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Inflow and outflow facies from the 1993 tsunami in southwest Hokkaido. (2006)
  • Author(s): Nanayama, F, Shigeno, K.
  • Journal Title: Sedimentary Geology 187 Pages: 139-158
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] 遡上津波堆積物概論-沿岸低地に残された津波堆積物に関する研究レビューと認定基準- (2004)
  • Author(s): 七山 太, 重野聖之
  • Journal Title: 地質学論集 58 Pages: 1-10
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] 2003年9月26日十勝沖地震津波の発生と残された教訓 (2004)
  • Author(s): 高橋智幸, 他13名
  • Journal Title: 海岸工学論文集 51 Pages: 1356-1360
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Large prehistorical tsunami traces at the historical site of Kokutaiji Temple and Shiomigawa lowland, eastern Hokkaido : significance of sedimentological and diatom analyses for recognition of past tsunami deposits. (2004)
  • Author(s): Soeda, Y, Nanayama, F, Shigeno, K, Furukawa, R, Kumasaki, N., Ishii, M.
  • Journal Title: Mem. Geol. Soc. Japan no. 58 Pages: 63-75
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] An overview of onshore tsunami deposits in coastal lowland and our sedimentological criteria to recognize them. (2004)
  • Author(s): Nanayama, F., Shigeno, K.
  • Journal Title: Mem. Geol. Soc. Japan no. 58 Pages: 19-33
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Earthquake- induced deposits : Importance and direction of future researchs in relation to disaster mitigation. (2004)
  • Author(s): Fujiwara, 0, Ikehara, K., Nanayama, F.
  • Journal Title: Mem. Geol. Soc. Japan no. 58 Pages: 1-10
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Tsunami run-up heights of the 2003 Tokachi-oki earthquake. (2004)
  • Author(s): Tanioka, Y, Nishimura, Y, Hirakawa, K, Imamura, F, Abe, I, Abe, Y, Shindou, K, Matsutomi, H, Takahashi, T, Imai, K, Harada, K, Namegawa, Y, Hasegawa, Y, Hayashi, Y, Nanayama, F, Kamataki, T, Kawata, Y, Fukasawa, Y, Koshimura, S, Hada, Y, Azumai, Y, Hirata, K, Tamikawa, A, Yoshikawa, A, Shiga, T, Masaka, S.
  • Journal Title: Earth Planet Space 56 Pages: 359-365
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Sedimentary characteristics and depositional processes of onshore tsunami deposits.
  • Author(s): Nanayama, F.
  • Journal Title: Tsunamiites - Features and Implications, Series title : Developments in Sedimentology (印刷中)
  • Description: 「研究成果報告書概要(和文)」より
• [Book] 産総研シリーズ 地震と活断層-過去から学び,将来を予測する-第5章海の地震,5.5過去の津波を調べる. (2004)
  • Author(s): 佐竹健治, 七山 太
  • Total Pages: 12
  • Publisher: 丸善
  • Description: 「研究成果報告書概要(和文)」より