Do turbidites provide a record of earthquakes and tsunamis? Examination by inverse analysis using deep learning neural network

• Project/Area Number: 20H01985
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 17030:Human geosciences-related
• Research Institution: Kyoto University
• Principal Investigator: 成瀬 元 京都大学, 理学研究科, 准教授 (40362438)
• Co-Investigator(Kenkyū-buntansha): 新井 和乃 高知大学, 海洋コア総合研究センター, 特任助教 (40757754)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Project Status: Completed (Fiscal Year 2023)
• Budget Amount: ¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000); Fiscal Year 2023: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000); Fiscal Year 2022: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2021: ¥6,370,000 (Direct Cost: ¥4,900,000、Indirect Cost: ¥1,470,000); Fiscal Year 2020: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
• Keywords: 逆解析 / 機械学習 / 堆積作用 / 混濁流 / 津波 / 海洋地質 / 深海地形 / 堆積学 / モーフォダイナミクス / 地形学 / ニューラルネットワーク / タービダイト / 海洋地質学 / 地質災害

Outline of Research at the Start

近年になり，巨大地震・津波イベントにより深海で混濁流が発生することが発見された．一方，混濁流は日常的な嵐や洪水でも発生することが観測から明らかになっている．タービダイトは，はたして巨大地震の指標となるのだろうか？この疑問を解決するため，本研究は地震性混濁流の流速や濃度を2011年東北沖津波起源のタービダイトから復元する．そして，得られた結果を現世で観測された嵐起源混濁流の水理条件と比較し，地震性混濁流が他の成因のものよりもはるかに大規模であるとする仮説を検証する．本研究の成果は，混濁流という現象の理解を通じて，巨大地震発生頻度の解明に貢献するだろう．

Outline of Annual Research Achievements

本研究は，深層学習逆解析を用いて，タービダイト（混濁流堆積物）を古地震指標として用いることの妥当性を検証することを目的としていた．この目的を達成するため，まず，タービダイトを含むイベント性堆積物の特徴からそれらを堆積させた流れの水理条件を復元する手法の開発をおこなった．本研究で開発した手法を人工データで検証したところ，比較的少数の露頭データからであっても，本研究が開発した深層学習逆解析によって津波や混濁流の特徴が的確に推定できることが示された．さらに，実際に2011年東北地方沖太平洋地震津波堆積物および2004年スマトラ沖地震堆積物の逆解析を行ったところ，これらの津波で観測された水理条件が高い精度で復元された．このことは，本研究の逆解析手法は過去の地震・津波イベントを的確に復元可能であることを示している．

本研究の手法を二つの地層のタービダイトに適用した．一つは更新統上総層群大田代層であり，もう一つは鮮新統安房層群である．大田代層のタービダイトで復元された混濁流の流速は6 m/s程度であり，現世で計測されている非地震性混濁流とおおむね同等の流速を示した．一方，安房層群のタービダイトでは15 m/sというきわめて高速な流れが復元された．この流速は現世の海底谷の直接観測では記録されたことのないレンジではあるが，地震性地すべりから発達した1929年Grand bank沖混濁流はこれに匹敵する流速で流下したことが海底ケーブル破断の時間間隔から推定されている．このことは，地層中にみられるタービダイトには多様な起源の混濁流から堆積したものが含まれていることを想起させる．今後は，本研究で開発した手法を多くの地層に適用し，極端に大きい流速・規模の混濁流を検出することで，巨大地震の発生頻度の復元が行われることが期待される．

Research Progress Status

令和5年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和5年度が最終年度であるため、記入しない。

Research Products

• [Journal Article] Cretaceous to early Paleogene sediment provenance transition from continental to magmatic arc systems in the Northwestern Pacific Region (2024)
  • Author(s): Harisma Harisma、Niki Sota、Hirata Takafumi、Naruse Hajime
  • Journal Title: Scientific Reports Volume: 14 Issue: 1 Pages: 7280-7280
  • DOI: 10.1038/s41598-024-55471-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Understanding flow characteristics from tsunami deposits at Odaka, Joban Coast, using a deep neural network (DNN) inverse model (2024)
  • Author(s): Mitra Rimali、Naruse Hajime、Abe Tomoya
  • Journal Title: Natural Hazards and Earth System Sciences Volume: 24 Issue: 2 Pages: 429-444
  • DOI: 10.5194/nhess-24-429-2024
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Abundance of trace fossil Phycosiphon incertum in core sections measured using a convolutional neural network (2024)
  • Author(s): Kikuchi Kazuki、Naruse Hajime
  • Journal Title: Sedimentary Geology Volume: 461 Pages: 106570-106570
  • DOI: 10.1016/j.sedgeo.2023.106570
  • Peer Reviewed
• [Journal Article] Understanding sedimentation, erosion, and geomorphological development of alluvial rivers through model experiments (2023)
  • Author(s): Naruse Hajime
  • Journal Title: The Journal of the Geological Society of Japan Volume: 129 Issue: 1 Pages: 441-452
  • DOI: 10.5575/geosoc.2023.0012
  • ISSN: 0016-7630, 1349-9963
  • Year and Date: 2023-08-09
  • Peer Reviewed
• [Journal Article] Flume experiments in the development of crevasse-splay deposits: transition from asymmetric to symmetric geometry (2023)
  • Author(s): Kato Taichi、Yamada Masaki、Naruse Hajime、Sakai Yuichi
  • Journal Title: Journal of Sedimentary Research Volume: 93 Issue: 11 Pages: 825-839
  • DOI: 10.2110/jsr.2023.029
  • Peer Reviewed
• [Journal Article] Linear-stability analysis of plane beds under flows with suspended loads (2023)
  • Author(s): Ohata Koji、Naruse Hajime、Izumi Norihiro
  • Journal Title: Earth Surface Dynamics Volume: 11 Issue: 5 Pages: 961-977
  • DOI: 10.5194/esurf-11-961-2023
  • Peer Reviewed / Open Access
• [Journal Article] Features of crevasse splay deposits and sedimentary processes associated with levee breaching due to the October 2019 flood of the Chikuma River, Central Japan (2023)
  • Author(s): Yamada Masaki、Naruse Hajime、Kuroda Yugo、Kato Taichi、Matsuda Yuhei、Shinozaki Tetsuya、Tokiwa Tetsuya
  • Journal Title: Natural Hazards Volume: 119 Issue: 1 Pages: 95-124
  • DOI: 10.1007/s11069-023-06122-7
  • Peer Reviewed
• [Journal Article] Conditions of submarine leveed channel inception: Examination by flume experiments (2023)
  • Author(s): Poppeschi Justine、Nakata Kazushi、Naruse Hajime
  • Journal Title: Sedimentology Volume: 70 Issue: 7 Pages: 2175-2195
  • DOI: 10.1111/sed.13117
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Inadequacy of fluvial energetics for describing gravity current autosuspension (2023)
  • Author(s): Fukuda Sojiro、de Vet Marijke G. W.、Skevington Edward W. G.、Bastianon Elena、Fern?ndez Roberto、Wu Xuxu、McCaffrey William D.、Naruse Hajime、Parsons Daniel R.、Dorrell Robert M.
  • Journal Title: Nature Communications Volume: 14 Issue: 1
  • DOI: 10.1038/s41467-023-37724-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Multiple scours and upward fining caused by hydraulic jumps: implications for the recognition of cyclic steps in the deepwater stratigraphic record (2023)
  • Author(s): Ono Kenya、Naruse Hajime、Yao Qifeng、Cai Zhirong、Fukuda Sojiro、Yokokawa Miwa
  • Journal Title: Journal of Sedimentary Research Volume: 93 Issue: 4 Pages: 243-255
  • DOI: 10.2110/jsr.2021.142
  • Peer Reviewed
• [Journal Article] Application of mineralogy and geochemistry to identify the landward extent of paleo-tsunami deposits not visible to the naked eye in the coastal wetland of Erimo, Hokkaido, Japan (2023)
  • Author(s): Nakanishi Ryo、Ashi Juichiro、Aizawa Masataka、Naruse Hajime
  • Journal Title: Sedimentary Geology Volume: 447 Pages: 106365-106365
  • DOI: 10.1016/j.sedgeo.2023.106365
  • Peer Reviewed
• [Journal Article] Density stratification controls the bedform phase diagram of saline‐gravity currents versus open‐channel flows (2023)
  • Author(s): Koji Ohata, Isabel de Cala, Robert M. Dorrell, Hajime Naruse, Stuart J. McLelland, Stephen M. Simmons, William D. McCaffrey
  • Journal Title: Sedimentology Volume: - Issue: 4 Pages: 1-27
  • DOI: 10.1111/sed.13075
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Upper and lower plane bed definitions revised (2022)
  • Author(s): Koji Ohata, Hajime Naruse, Norihiro Izumi
  • Journal Title: Progress in Earth and Planetary Science Volume: 9 Issue: 1 Pages: 23-35
  • DOI: 10.1186/s40645-022-00481-8
  • Peer Reviewed / Open Access
• [Journal Article] The Origin of the Paleo-Kuril Arc, NE Japan: Sediment Provenance Change and Its Implications for Plate Configuration in the NW Pacific Region Since the Late Cretaceous (2022)
  • Author(s): H. Harisma, H. Naruse, H. Asanuma, T. Hirata
  • Journal Title: Tectonics Volume: 41 Issue: 12
  • DOI: 10.1029/2022tc007299
  • Peer Reviewed / Open Access
• [Journal Article] Morphological Function of Trace Fossil Paleodictyon: an Approach from Fluid Simulation (2022)
  • Author(s): Kikuchi Kazuki、Naruse Hajime
  • Journal Title: Paleontological Research Volume: 26 Issue: 4 Pages: 378-389
  • DOI: 10.2517/pr210001
  • Peer Reviewed
• [Journal Article] High-resolution upper Maastrichtian carbon isotope stratigraphy of terrestrial organic matter from northern Japan (2022)
  • Author(s): Nifuku, K., Naruse, H., & Ikehara, M.
  • Journal Title: Newsletters on Stratigraphy Volume: 55 Issue: 2 Pages: 137-157
  • DOI: 10.1127/nos/2021/0652
  • Peer Reviewed
• [Journal Article] Inverse modeling of turbidity currents using an artificial neural network approach: verification for field application. (2021)
  • Author(s): Naruse, H., & Nakao, K.
  • Journal Title: Earth Surface Dynamics Volume: 9 Issue: 5 Pages: 1091-1109
  • DOI: 10.5194/esurf-9-1091-2021
  • Peer Reviewed / Open Access
• [Journal Article] Inverse analysis of experimental scale turbidity currents using deep learning neural networks (2021)
  • Author(s): Cai, Z., & Naruse, H.
  • Journal Title: Journal of Geophysical Research: Earth Surface Volume: 126 Issue: 8
  • DOI: 10.1029/2021jf006276
  • NAID: 120007192874
  • Peer Reviewed
• [Journal Article] Reconstruction of flow conditions from 2004 Indian Ocean tsunami deposits at the Phra Thong island using a deep neural network inverse model (2021)
  • Author(s): Mitra Rimali、Naruse Hajime、Fujino Shigehiro
  • Journal Title: Natural Hazards and Earth System Sciences Volume: 21 Issue: 5 Pages: 1667-1683
  • DOI: 10.5194/nhess-21-1667-2021
  • Peer Reviewed / Open Access
• [Journal Article] Reconstruction of flow conditions from 2004 Indian Ocean tsunamideposits at the Phra Thong island using a deep neural networkinverse model (2021)
  • Author(s): Mitra Rimali、Naruse Hajime、Fujino Shigehiro
  • Journal Title: Natural Hazards and Earth System Sciences Volume: 0 Pages: 1-23
  • DOI: 10.5194/nhess-2020-373
  • Peer Reviewed
• [Journal Article] Shape difference of mud clasts depending on depositional facies: application of newly modified elliptic Fourier analysis to hybrid event beds (2020)
  • Author(s): Fukuda Sojiro、Naruse Hajime
  • Journal Title: Journal of Sedimentary Research Volume: 90 Issue: 10 Pages: 1410-1435
  • DOI: 10.2110/jsr.2020.67
  • Peer Reviewed
• [Journal Article] Relating the Flow Processes and Bedforms of Steady-State and Waning Density Currents (2020)
  • Author(s): de Cala Isabel、Ohata Koji、Dorrell Robert、Naruse Hajime、Patacci Marco、Amy Lawrence A.、Simmons Steve、McLelland Stuart J.、McCaffrey William D.
  • Journal Title: Frontiers in Earth Science Volume: 8 Pages: 535743-535743
  • DOI: 10.3389/feart.2020.535743
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Estimation of Tsunami Characteristics from Deposits: Inverse Modeling Using a Deep‐Learning Neural Network (2020)
  • Author(s): Mitra Rimali、Naruse Hajime、Abe Tomoya
  • Journal Title: Journal of Geophysical Research: Earth Surface Volume: 125 Issue: 9
  • DOI: 10.1029/2020jf005583
  • Peer Reviewed
• [Journal Article] Bed-thickness frequency distributions and recurrence intervals of sediment-gravity-flow deposits intercalated in lacustrine varved diatomite: examples from the middle Pleistocene Hiruzenbara Formation, southwest Japan (2020)
  • Author(s): Sasaki Hana、Sasaki Yasunori、Saito-Kato Megumi、Naruse Hajime、Ishihara Yoshiro
  • Journal Title: Journal of Sedimentary Research Volume: 90 Issue: 6 Pages: 561-572
  • DOI: 10.2110/jsr.2020.28
  • Peer Reviewed
• [Presentation] Reconstruction of paleohydraulic conditions of turbidity currents from geologic records considering uncertainties: inverse analysis of turbidites using Bayesian neurual network (2023)
  • Author(s): Hajime Naruse
  • Organizer: AGU Fall Meeting 2023
  • Int'l Joint Research
• [Presentation] 古第三紀における古千島弧での砕屑物供給源変化と海嶺沈み込み：砕屑性ジルコン年代分布のBayesian population correlation 解析 (2023)
  • Author(s): 成瀬 元,Buburanda Harisma,平田 岳史,仁木 創太
  • Organizer: 日本地質学会第130年学術大会
• [Presentation] 河川と混濁流のつくるクレバススプレイ堆積物の違い：数値実験による検討 (2023)
  • Author(s): 成瀬 元,山田 昌樹,酒井 祐一
  • Organizer: 日本地質学会第130年学術大会
• [Presentation] 機械学習の堆積学への応用：露頭とモデルをつなぐ (2023)
  • Author(s): 成瀬 元
  • Organizer: 石油技術協会春季講演会
• [Presentation] クレバススプレイ地形の発達過程の実験的検討 (2023)
  • Author(s): 成瀬 元,山田 昌樹,加藤 汰一
  • Organizer: 日本地球惑星科学連合2023年大会
  • Int'l Joint Research
• [Presentation] 海底の土砂動態：浮遊砂輸送モデリングの課題 (2023)
  • Author(s): 成瀬 元
  • Organizer: 日本地球惑星科学連合2023年大会
  • Int'l Joint Research
• [Presentation] 生物攪拌が地質記録に与える影響の除去:格子オートマトン-逆畳み込み法 (2023)
  • Author(s): 成瀬 元
  • Organizer: 日本堆積学会2023年大会
• [Presentation] Filtering effect to the scale of turbidity currents in submarine canyons (2022)
  • Author(s): Hajime Naruse
  • Organizer: AGU Fall meeting 2023
  • Int'l Joint Research
• [Presentation] Uncertainty estimation of the flow conditions of particulate gravity currents reconstructed by deep neural network (2022)
  • Author(s): Hajime Naruse
  • Organizer: Particulate Gravity Currents 2022
  • Int'l Joint Research
• [Presentation] 重力流堆積物逆解析の不確実性の評価 (2022)
  • Author(s): 成瀬 元
  • Organizer: 日本地球惑星科学連合2022年大会
• [Presentation] 石垣島カラダギ洞窟に流入した先島津波の規模:３次元数値実験による検討 (2022)
  • Author(s): 成瀬 元・石原与四郎
  • Organizer: 日本堆積学会2022年大会
• [Presentation] Reconstruction of crustal uplift history in island arcs by inversion of river longitudinal profile: consideration of basement rock strength and sea-level change (2021)
  • Author(s): Hajime Naruse
  • Organizer: AGU Fall Meeting 2021
  • Int'l Joint Research
• [Presentation] 岩盤河川縦断形状に基づく日本列島隆起速度のベイズ推定 (2021)
  • Author(s): 成瀬 元
  • Organizer: 日本地質学会2021年大会
• [Presentation] 復元の科学としての堆積学 (2021)
  • Author(s): 成瀬 元
  • Organizer: 日本地球惑星科学連合2021年大会
  • Int'l Joint Research / Invited
• [Presentation] Grain size segregation on cyclic steps formed by turbidity currents (2021)
  • Author(s): Hajime Naruse
  • Organizer: 日本地球惑星科学連合2021年大会
  • Int'l Joint Research
• [Presentation] Cyclic steps inside submarine canyon and in canyon-fan transition zone: Numerical experiments by 2D shallow-water model of turbidity currents (2020)
  • Author(s): Hajime Naruse
  • Organizer: JpGU-AGU Joint Meeting 2020
  • Int'l Joint Research
• [Presentation] Inverse Analysis of Experimental Scale Turbidity Currents by Deep Learning Neural Network (2020)
  • Author(s): Cai Zhirong and Hajime Naruse
  • Organizer: JpGU-AGU Joint Meeting 2020
  • Int'l Joint Research
• [Presentation] Morphological diversity of cyclic steps at submarine canyon-fan transition zone: A two dimensional numerical modeling approach (2020)
  • Author(s): Hajime Naruse
  • Organizer: American Geophysical Union 2020 Fall Meeting
  • Int'l Joint Research
• [Book] フィールドマニュアル 図説 堆積構造の世界 (2022)
  • Author(s): 日本堆積学会、伊藤 慎
  • Total Pages: 210
  • Publisher: 朝倉書店
  • ISBN: 9784254162790