Article
Multidisciplinary Sciences
Piero Bellanova, Mike Frenken, Yuichi Nishimura, Jan Schwarzbauer, Klaus Reicherter
Summary: The 2011 Tohoku-oki tsunami caused massive damage along the northern Japanese Aomori coast, with the coastal control area being inundated up to 550 m inland. A previously undocumented woody-organic tsunami deposit was discovered, improving understanding of the documented part of the tsunami inundation and reducing underestimation.
SCIENTIFIC REPORTS
(2021)
Review
Geochemistry & Geophysics
N. Uchida, R. Burgmann
Summary: Research has shown that there were indications of a potential great megathrust earthquake in NE Japan before the 2011 Tohoku earthquake, but a consensus assessment of the hazard was lacking. Since the earthquake, studies have made significant progress in revealing aspects such as coseismic rupture, aftershocks, and slow earthquakes.
REVIEWS OF GEOPHYSICS
(2021)
Article
Multidisciplinary Sciences
Ken Ikehara, Tomohisa Irino, Yoshiki Saito
Summary: The study compared surface sediments before and after the 2011 Tohoku-oki tsunami on the Sendai shelf and found that both sandy and muddy sediments were significantly reworked by the tsunami. Part of the resuspended mud moved offshore to the slope area as turbidity currents.
SCIENTIFIC REPORTS
(2021)
Article
Geology
Ken Ikehara, Kazuko Usami, Tomohisa Irino, Akiko Omura, Robert G. Jenkins, Juichiro Ashi
Summary: Deep-sea turbidite deposits are valuable tools for submarine paleoseismology. By analyzing the event deposits from the 2011 Tohoku-oki earthquake and tsunami, researchers found that the deposits originated from multiple sources, indicating widespread seafloor disturbances. Different types of event deposits reflect varying sediment transport pathways, with limited long-distance transport observed despite the wide spatial distribution.
SEDIMENTARY GEOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Liming He, Lixin Wu, Kosuke Heki, Cong Guo
Summary: This study presents the anomalities of total electron content in the ionosphere before the 2011 M(w)9.0 Tohoku-oki earthquake, observed in northern Australia by the Global Navigation Satellite System (GNSS) stations. The onset time of the anomaly, determined by the Akaike's information criterion, is very close to the time observed in Japan. The positive TEC anomalies in Australia appear on the same longitude as the land area of NE Japan, supporting the model that electric fields within the ionosphere redistribute the electrons before large earthquakes.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Multidisciplinary Sciences
Shohei Iwai, Kazuhisa Goto
Summary: This study collected the first comprehensive dataset for the Sanriku coast of Japan, revealing that the 2011 Tohoku-oki tsunami moved approximately 1500 tons of boulders and concrete blocks with a flow depth of around 28 meters. It was also found that most boulders that remained unmoved were influenced more by local settings rather than their heavy weights. The threshold for moved/unmoved boulders was estimated against the flow depth, indicating that flow depths of over 20 meters are needed to move boulders weighing over 1000 tons.
SCIENTIFIC REPORTS
(2021)
Article
Geology
Yasutaka Iijima, Kazuhisa Goto, Daisuke Sugawara, Tomoya Abe
Summary: This study focuses on the relationship between artificial structures, sedimentary structures, and hydrodynamics of the 2011 Tohoku-oki tsunami. Field observations showed that coastal dikes and roadways significantly influenced the source, thickness, and sedimentary structures of the tsunami deposits, providing insight into the depositional processes.
SEDIMENTARY GEOLOGY
(2021)
Article
Remote Sensing
Ankang Ren, Keke Xu, Zhenhua Shao, Xinqi Liu, Xiaoyi Wang
Summary: It is found that colored noise in GNSS time series has significant impact on parameter estimation of general linear trajectory models. To overcome this issue, maximum likelihood estimation is used to estimate the colored noise and a nonlinear least square algorithm with colored noise as the stochastic model is employed to calculate timescale parameters. The method is validated through simulation experiments and has shown significant improvements in reducing iteration times and decreasing parameter estimation deviations compared to traditional methods.
Article
Engineering, Aerospace
Keke Xu, Rong He, Kezhao Li, Ankang Ren, Zhenhua Shao
Summary: By focusing on high-precision GNSS data processing and analysis, the study reveals the dynamic evolution of tectonics and crustal deformation along subduction zones. Common Mode Errors are removed, deformation signals are extracted, and regional spatiotemporal filtering is utilized to comprehensively display crustal motion characteristics.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Yuki Kodera, Naoki Hayashimoto, Koji Tamaribuchi, Keishi Noguchi, Ken Moriwaki, Ryo Takahashi, Masahiko Morimoto, Kuninori Okamoto, Mitsuyuki Hoshiba
Summary: After the 2011 Tohoku-Oki earthquake, the Japan Meteorological Agency made significant improvements to their earthquake early warning system by implementing new ground motion prediction methods and incorporating new observation facilities. These updates enhanced the accuracy and timeliness of earthquake predictions, showing substantial progress over the 10 years since the Tohoku-Oki earthquake.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geography, Physical
Haruki Imura, Kazuhisa Goto, Kenta Minamidate, Naoto Koiwa
Summary: This study investigated the topographic changes caused by the 2011 Tohoku-oki tsunami and other natural and artificial activities at the Osuka coast in Aomori prefecture, Japan. The findings showed that the tsunami generated significant topographic changes, which were preserved underground even after 10 years. However, the dynamic movement of the dunes was caused by deforestation rather than the tsunami effects. This highlights the importance of considering both natural and artificial factors in coastal geomorphology.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Chemistry, Analytical
Dong-Hyo Sohn, Byung-Kyu Choi, Sungshil Kim, Sun-Cheon Park, Won-Jin Lee, Pil-Ho Park
Summary: The study on decaying post-seismic deformation on the Korean Peninsula indicates that crustal movement is gradually returning to its pre-earthquake motion, with the recovery pattern influenced by regional geologic structures and time.
Article
Geosciences, Multidisciplinary
Mike Frenken, Piero Bellanova, Yuichi Nishimura, Klaus Reicherter, Jan Schwarzbauer
Summary: The 2011 Tohoku-oki tsunami left a characteristic geochemical signature in the sediments of the Misawa harbor on the Aomori coastline, with specific compounds illustrating different emission sources and distribution during the tsunami. Petrogenic-derived markers provide information about tsunami-related destruction, sewage-derived compounds were widely distributed from a diffuse source, and old burden markers signal erosion and rearrangement of contaminants prior to the tsunami.
Correction
Multidisciplinary Sciences
Su-Yang Wang, Hai-Yang Zhuang, Hao Zhang, Hong-Jun He, Wei-Ping Jiang, Er-Lei Yao, Bin Ruan, Yong-Xin Wu, Yu Miao
Summary: A correction to the paper has been published.
NATURE COMMUNICATIONS
(2021)
Review
Geosciences, Multidisciplinary
Kazuhisa Goto, Takashi Ishizawa, Yuichi Ebina, Fumihiko Imamura, Shosuke Sato, Keiko Udo
Summary: The 2011 Tohoku-oki earthquake and tsunami had devastating effects on coastal environments, but many of these impacts have since naturally or artificially recovered. Despite efforts by the government to prepare for future events, there is still uncertainty in forecasting tsunamis and raising public awareness. The challenges of predicting low-frequency tsunami events and fostering a social consensus for preparedness remain unresolved since the 2011 event.
EARTH-SCIENCE REVIEWS
(2021)
Article
Environmental Sciences
Ryota Nakajima, Masashi Tsuchiya, Akinori Yabuki, Shuhei Masuda, Tomo Kitahashi, Yuriko Nagano, Tetsuro Ikuta, Noriyuki Isobe, Haruhiko Nakata, Heather Ritchie, Kazumasa Oguri, Satoshi Osafune, Kiichiro Kawamura, Maki Suzukawa, Takuya Yamauchi, Koichi Iijima, Takao Yoshida, Sanae Chiba, Katsunori Fujikura
Summary: This study used video imagery to quantitatively assess plastic debris on the abyssal seafloor in the Northwest Pacific, revealing the highest density of plastic debris recorded for an abyssal plain, indicating it as a significant reservoir for plastic debris.
MARINE POLLUTION BULLETIN
(2021)
Article
Environmental Sciences
Ryota Nakajima, Toru Miyama, Tomo Kitahashi, Noriyuki Isobe, Yuriko Nagano, Tetsuro Ikuta, Kazumasa Oguri, Masashi Tsuchiya, Takao Yoshida, Kunihiro Aoki, Yosaku Maeda, Kiichiro Kawamura, Maki Suzukawa, Takuya Yamauchi, Heather Ritchie, Katsunori Fujikura, Akinori Yabuki
Summary: Extreme storms can transport a significant amount of plastic debris from land to sea, including microplastics and mesoplastics. After a typhoon, the concentrations of micro- and mesoplastics increase drastically, but return to pre-typhoon levels within a short period of time. Therefore, it is important to consider the impact of extreme storms on plastic debris leakage when estimating the annual load of plastics from land to sea.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Geochemistry & Geophysics
Keiichi Ishizu, Weerachai Siripunvaraporn, Tada-nori Goto, Katsuaki Koike, Takafumi Kasaya, Hisanori Iwamoto
Summary: This study presents a cost-effective 3D marine controlled-source electromagnetic (CSEM) survey method for exploring seafloor massive sulfides (SMS). By using fewer receivers and a line configuration, the survey reduces costs while accurately mapping SMS.
Article
Construction & Building Technology
Keisuke Takahashi, Yuichiro Kawabata, Mitsuyasu Iwanami, Mari Kobayashi, Takafumi Kasaya, Toshiro Yamanaka, Shun Nomura, Hiroko Makita
Summary: The results of the first-ever in-situ monitoring of a large mortar specimen at a depth of 3515 m in the Nankai Trough are presented in this study. The study successfully monitored the development of strain and hydraulic pressure in the specimen. However, microstructural damage was observed in the specimen after exposure to the deep sea environment for one year, resulting in a decrease in compressive strength and Young's modulus.
JOURNAL OF ADVANCED CONCRETE TECHNOLOGY
(2022)
Article
Chemistry, Analytical
Taku Yutani, Oak Yono, Tatsu Kuwatani, Daisuke Matsuoka, Junji Kaneko, Mitsuko Hidaka, Takafumi Kasaya, Yukari Kido, Yoichi Ishikawa, Toshiaki Ueki, Eiichi Kikawa
Summary: This study proposes a method for improving the production of bathymetric maps using dictionary learning and sparse coding techniques. By modifying the super-resolution technique, the method achieves better accuracy and reduces errors compared to traditional methods. Pre-processing and training the dictionary allow for the capture and reconstruction of detailed topographical features, resulting in high interpretability.
Article
Geosciences, Multidisciplinary
Koji Ohata, Hajime Naruse, Norihiro Izumi
Summary: This study presents phase diagrams based on existing data to clarify the formative processes of plane beds in sedimentary structures. The results indicate that lower plane beds are formed by bed load movement of sediment particles, while upper plane beds appear under conditions of active suspended load. The study suggests that existing interpretations of fine-grained parallel lamination need to be reconsidered.
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2022)
Article
Geochemistry & Geophysics
Takafumi Kasaya, Yoshifumi Nogi, Kazuya Kitada
Summary: Marine magnetic field surveys near the seafloor are valuable for studying volcanic eruption, active hydrothermal systems, and hydrothermal deposit evolution. To conduct accurate magnetic surveys using autonomous underwater vehicles (AUVs), correcting for the vehicle's attitude-induced magnetic field anomalies, especially pitch changes, is essential.
EXPLORATION GEOPHYSICS
(2023)
Article
Paleontology
Kazuki Kikuchi, Hajime Naruse
Summary: This study used computational fluid dynamics and numerical experiments to investigate the functional morphology of the trace fossil Paleodictyon. The results showed that this fossil has a unique morphology that allows for ventilation and supply of oxygenated water and food. The height of the shield-like mounds observed in modern specimens may be optimized for balancing ventilation efficiency and physical stability against erosion.
PALEONTOLOGICAL RESEARCH
(2022)
Article
Geology
Koji Ohata, Isabel de Cala, Robert M. Dorrell, Hajime Naruse, Stuart J. McLelland, Stephen M. Simmons, William D. McCaffrey
Summary: Sedimentary bedforms such as ripples and dunes can be generated by both river flows and sediment-laden gravity currents. Existing bedform phase diagrams based on open-channel flow data may not be applicable to gravity current deposits due to the fundamentally different nature of gravity current hydrodynamics. New experiments show that using parameters based on the lower layer of stratified gravity currents improves the prediction of bedform type compared to traditional bedform phase diagrams. These findings highlight the importance of considering the characteristics of the lower layer when accurately predicting bedforms produced by gravity currents.
Article
Geochemistry & Geophysics
H. Harisma, H. Naruse, H. Asanuma, T. Hirata
Summary: By analyzing detrital zircon U-Pb ages, this study reveals the development of Paleo-Kuril Arc as a continental arc during the Late Cretaceous, rather than an intraoceanic arc.
Article
Geology
Ryo Nakanishi, Juichiro Ashi, Masataka Aizawa, Hajime Naruse
Summary: The extent of past tsunami inundation can be reconstructed using deposits in geologic records. However, visible tsunami deposits do not cover the entire inundation extent, necessitating the identification of macroscopically invisible traces for accurate reconstruction. This study proposes a composite method based on mineral particles with high preservation potential. Multiple proxies, including non-destructive methods and mineralogical and grain size analyses, are used. The method was applied in Erimo, Japan to detect macroscopically invisible particles that share a common source with observable tsunami sand. The predicted inundation extent using the inverse model FITTNUSS-DNN was comparable to the distribution of the macroscopically invisible sand.
SEDIMENTARY GEOLOGY
(2023)
Article
Geology
Justine Poppeschi, Kazushi Nakata, Hajime Naruse
Summary: Submarine leveed channels are common in submarine fans, but their formation parameters have not been studied. This study conducted four experimental series to simulate and study the conditions for the formation of submarine channels. The experiments showed that dilute flows can form purely depositional channel levees without erosive features. The formation of submarine channels is related to channel width and muddy suspended sediment.
Article
Multidisciplinary Sciences
Sojiro Fukuda, Marijke G. W. de Vet, Edward W. G. Skevington, Elena Bastianon, Roberto Fernandez, Xuxu Wu, William D. McCaffrey, Hajime Naruse, Daniel R. Parsons, Robert M. Dorrell
Summary: Gravity currents, such as sediment-laden turbidity currents, are natural flows that are driven by a density difference. Material transport in gravity currents is fundamentally different from fluvial systems, and the current understanding is insufficient. Research shows that buoyancy production in gravity currents has a non-linear dependence on available flow power, indicating an underestimation of total kinetic energy lost.
NATURE COMMUNICATIONS
(2023)
Article
Geology
Taichi Kato, Masaki Yamada, Hajime Naruse, Yuichi Sakai
Summary: Crevasse-splay deposits are important for understanding past flood events and river behavior. This study used scaled flume experiments to investigate the relationship between the development of crevasse splays and their characteristics. The results revealed important findings about the geometry, development regions, and sediment characteristics of crevasse-splay deposits.
JOURNAL OF SEDIMENTARY RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Masaki Yamada, Hajime Naruse, Yugo Kuroda, Taichi Kato, Yuhei Matsuda, Tetsuya Shinozaki, Tetsuya Tokiwa
Summary: Field investigations and analyses of modern crevasse splay deposits are important for understanding levee breaching processes and estimating ancient river floods. The 2019 flooding of the Chikuma River in Japan resulted in the formation of crevasse splay deposits divided into three regions: proximal splay with gravelly and sandy sediment piles, medial splay with sandy deposits, and distal splay with muddy deposits. The sedimentary characteristics of these deposits provide valuable information for studying past and future levee breaches.
