Article
Geochemistry & Geophysics
Keisuke Yoshida, Naoki Uchida, Hisahiko Kubo, Ryota Takagi, Shiqing Xu
Summary: The development of seafloor seismic observations has enabled the reliable estimation of rupture directivities from offshore earthquakes. The study found that the majority of earthquakes have directional ruptures favoring updip propagation, which may be related to deep aseismic slip and upward fluid migration along the plate interface.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Keisuke Yoshida, Naoki Uchida, Yoshiaki Matsumoto, Masaki Orimo, Tomomi Okada, Satoshi Hirahara, Shuutoku Kimura, Ryota Hino
Summary: A M-w 6.2 earthquake occurred in Suzu, northeastern Noto Peninsula, Japan, on May 5, 2023, following a 2.5-year intense earthquake swarm. The mainshock rupture was initiated near the shallow end of the preceding swarm earthquakes, with systematic upward migration likely caused by fluid movement. The results emphasize the importance of monitoring swarm events, as they can lead to large and dangerous earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Lou Marill, David Marsan, Anne Socquet, Mathilde Radiguet, Nathalie Cotte, Baptiste Rousset
Summary: The study utilized GPS data to analyze the unlocking process from 1997 to 2011 along the coast of Honshu, revealing changes in slip rates at different latitudes and a novel unlocking phenomenon south of 36 degrees latitude, unrelated to the 2011 Tohoku earthquake.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
Xingyue Wang, Lingmin Cao, Minghui Zhao, Jinhui Cheng, Xiaobo He
Summary: Subduction zones are important interfaces for material exchange between the Earth's crust and mantle. This study investigates atypical subduction in subduction zones such as the Mussau Trench, the Hjort Trench, and the Gagua Ridge. The findings suggest that atypical subduction may occur when the plate boundary is characterized by strike-slip-dominated transpression and when there is subduction polarity reversal and a strike-slip border.
Review
Geosciences, Multidisciplinary
Tomoaki Nishikawa, Satoshi Ide, Takuya Nishimura
Summary: This paper reviews studies on slow earthquakes along the Japan Trench, including observations, experiments, and simulations. By integrating these studies and analyzing the relationship between slow earthquakes and the crustal structure and geological environment of the Japan Trench, the authors discuss their role in the occurrence process of the Tohoku-Oki earthquake. The paper also suggests that detailed monitoring of slow earthquake activity can improve the forecasts of interplate seismicity along the Japan Trench.
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2023)
Article
Engineering, Civil
Hongjun Si, Saburoh Midorikawa, Tadahiro Kishida
Summary: An empirical ground-motion model for subduction earthquakes in Japan was developed, taking into account various parameters and covering a range of events that occurred in Japan.
EARTHQUAKE SPECTRA
(2022)
Article
Geochemistry & Geophysics
Tomoaki Nishikawa, Takuya Nishimura, Yutaro Okada
Summary: The study detected earthquake swarms along the Hikurangi Trench in New Zealand using the ETAS model, finding that most earthquake swarm sequences were intraplate events concentrated along the east coast of the North Island. Some earthquake swarms occurred several days before slow slip events, suggesting that SSE-induced stress loading may not be the triggering mechanism for these pre-SSE earthquake swarms.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
Huizi Jian, Ting Yang, Zhihao Chen, Lingling Ye, Jiashun Hu, Peng Guo
Summary: The study shows that slab pull from the Ryukyu Trench can transmit through the weakened Philippine Sea Plate and drive the advance of the Izu-Bonin Trench without the need for extreme rheological parameters. This research is of great importance for understanding subduction dynamics, lithospheric deformation mechanisms, and slab rheology.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Yanfang Qin, Yasuyuki Nakamura, Shuichi Kodaira, Gou Fujie
Summary: This study collected seismic data from different regions along the Japan trench during the 2011 Tohoku earthquake to investigate the impact of along-trench structures on seismic activities. The study found variations in geological structures, such as differences in sediment thickness and the presence of fold-and-thrust belts in the south. These structural variations influence shallow megathrust slip and tsunami generation.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Yoshio Fukao, Tatsuya Kubota, Hiroko Sugioka, Aki Ito, Takashi Tonegawa, Hajime Shiobara, Mikiya Yamashita, Tatsuhiko Saito
Summary: The study deployed ocean bottom pressure gauges at the Izu-Bonin Trench and observed that subduction mainly occurs through aseismic slip. Two much larger aseismic slip events were detected near a Mw6.0 thrust earthquake, with the total moment 17 times larger than that of the mainshock. This kind of slip may represent a transitional regime in the subduction zone, where slow slip events are expected to occur near its boundaries with stable sliding and unstable seismic slip regimes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Zhi Wang, Jian Lin
Summary: The frequent occurrence of large thrust earthquakes and subsequent tsunamis in a subduction zone are attributed to multiple factors, including structural heterogeneity, fluid saturation, and topographic variations of the subducting oceanic plate. This study investigates the impact of these factors on the 2021 Mw 7.1 Fukushima-Oki earthquake and interplate seismic coupling in the northeastern Japan subduction zone. The results reveal that high-V zones with high-density thrust earthquakes indicate strong interplate seismic coupling, while low-V patches reflect weak interplate coupling or decoupling. Additionally, seamount subduction plays a significant role in seismography and the mechanical strength variation of interplate coupling in the forearc seismogenic zone.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Masayuki Kano, Aoi Ikeuchi, Takuya Nishimura, Shin'ichi Miyazaki, Takeshi Matsushima
Summary: The research analyzed Global Navigation Satellite System data from 2010 to 2021 to study crustal movements in the southern part of the Ryukyu subduction zone, where a large slip deficit area was identified that could potentially trigger a major earthquake. The study findings suggest that seafloor geodetic observations are essential for understanding the spatial distribution of slip deficit and discussing earthquake and tsunami potential.
EARTH PLANETS AND SPACE
(2021)
Article
Geochemistry & Geophysics
Yuyang Tan, Huilin Xing, Zongwei Jin, Jianchao Wang, Shuo Pang, Hao Guo, Haijiang Zhang, Lei Gao
Summary: This study applied a Vp/Vs model-consistency constrained double-difference seismic tomography method to investigate the cause of an earthquake in the Pacific coast of northeastern Japan and its aftershocks. The findings suggest that the earthquake sequence is likely the result of the reactivation of a pre-existing fault caused by dehydration of the mantle serpentines. The velocity structures at the hypocenter areas also contribute to the understanding of the nucleation process of the earthquake sequence.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Ao Zheng, Xiangwei Yu, Jiaqi Qian, Wenbo Zhang
Summary: The convergence of the Pacific and Okhotsk plates has led to the formation of the Japan Trench subduction zone. Two large earthquakes, known as the Fukushima-Oki earthquake doublet, occurred in the offshore region of Fukushima. Both earthquakes are intraslab events characterized by thrust motions. The reactivation of preexisting bending-related faults within the subducting Pacific plate, driven by downdip compressional stress, is believed to be the cause of the doublet.
Article
Geochemistry & Geophysics
B. Gombert, J. C. Hawthorne
Summary: Slow earthquakes can have varying durations, moments, and slip and propagation speeds. This study examines tremor bursts with durations between 1 and 30 minutes, which are likely driven by short bursts of aseismic slip. Using a coherence-based technique, thousands of tremor bursts beneath Vancouver Island in Cascadia are detected, and 17 of the ruptures are examined. The study finds that tremor migrates at rates of 3-25 m/s, filling a gap in the spectrum of observed slow earthquakes and suggesting the existence of faster slip and propagation in smaller ruptures.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geosciences, Multidisciplinary
Junichi Nakajima, Naoki Uchida
Review
Astronomy & Astrophysics
Naoki Uchida, Roland Burgmann
ANNUAL REVIEW OF EARTH AND PLANETARY SCIENCES, VOL 47
(2019)
Article
Geosciences, Multidisciplinary
Kei Katsumata, Masayoshi Ichiyanagi, Mako Ohzono, Hiroshi Aoyama, Ryo Tanaka, Masamitsu Takada, Teruhiro Yamaguchi, Kazumi Okada, Hiroaki Takahashi, Shin'ichi Sakai, Satoshi Matsumoto, Tomomi Okada, Toru Matsuzawa, Shuichiro Hirano, Toshiko Terakawa, Shinichiro Horikawa, Masahiro Kosuga, Hiroshi Katao, Yoshihisa Iio, Airi Nagaoka, Noriko Tsumura, Tomotake Ueno, Koji Miyakawa, Shin'ichi Tanaka, Miwako Ando, Naoki Uchida, Ryosuke Azuma, Ryota Takagi, Keisuke Yoshida, Takashi Nakayama, Satoshi Hirahara, Yoshiko Yamanaka, Yuta Maeda, Shuichiro Hirano, Hiroki Miyamachi, Hiroshi Yakiwara, Takuto Maeda, Masahiro Shimazaki, Youichi Asano
EARTH PLANETS AND SPACE
(2019)
Article
Geochemistry & Geophysics
C. Honsho, M. Kido, F. Tomita, N. Uchida
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2019)
Article
Geochemistry & Geophysics
Ryota Takagi, Naoki Uchida, Kazushige Obara
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2019)
Review
Geosciences, Multidisciplinary
Naoki Uchida
PROGRESS IN EARTH AND PLANETARY SCIENCE
(2019)
Article
Multidisciplinary Sciences
T. Nishikawa, T. Matsuzawa, K. Ohta, N. Uchida, T. Nishimura, S. Ide
Article
Geochemistry & Geophysics
N. Uchida, D. Kalafat, A. Pinar, Y. Yamamoto
Article
Geosciences, Multidisciplinary
Aki Ito, Takashi Tonegawa, Naoki Uchida, Yojiro Yamamoto, Daisuke Suetsugu, Ryota Hino, Hiroko Sugioka, Koichiro Obana, Kazuo Nakahigashi, Masanao Shinohara
EARTH PLANETS AND SPACE
(2019)
Article
Geosciences, Multidisciplinary
Yo Fukushima, Manabu Hashimoto, Masatoshi Miyazawa, Naoki Uchida, Taka'aki Taira
EARTH PLANETS AND SPACE
(2019)
Article
Geochemistry & Geophysics
Naoki Uchida, Ryota Takagi, Youichi Asano, Kazushige Obara
EARTH AND PLANETARY SCIENCE LETTERS
(2020)
Article
Geochemistry & Geophysics
Mostafa Khoshmanesh, Manoochehr Shirzaei, Naoki Uchida
EARTH AND PLANETARY SCIENCE LETTERS
(2020)
Article
Geosciences, Multidisciplinary
Fumiaki Tomita, Takeshi Iinuma, Yusaku Ohta, Ryota Hino, Motoyuki Kido, Naoki Uchida
EARTH PLANETS AND SPACE
(2020)
Article
Geochemistry & Geophysics
Keisuke Yoshida, Naoki Uchida, Satoshi Hiarahara, Takashi Nakayama, Toru Matsuzawa, Tomomi Okada, Yoshiaki Matsumoto, Akira Hasegawa
Article
Multidisciplinary Sciences
Naoki Uchida, Junichi Nakajima, Kelin Wang, Ryota Takagi, Keisuke Yoshida, Takashi Nakayama, Ryota Hino, Tomomi Okada, Youichi Asano
NATURE COMMUNICATIONS
(2020)
Article
Geochemistry & Geophysics
Lingyu Zhang, Kristoffer Szilas
Summary: This study presents new petrological and geochemical data for the Narssaq Ultramafic Body (NUB) in the Itsaq Gneiss Complex of SW Greenland. The results indicate that the ultramafic rocks of NUB are not mantle residues, but instead represent crustal cumulates derived from high-Mg magmas.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Rong Xu, Sarah Lambart, Oliver Nebel, Ming Li, Zhongjie Bai, Junbo Zhang, Ganglan Zhang, Jianfeng Gao, Hong Zhong, Yongsheng Liu
Summary: This study investigated the iron isotope compositions of Cenozoic basalts in Southeast China, finding significant variations related to different types of basalts and their respective sources.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
C. J. Ebinger, Miriam C. Reiss, Ian Bastow, Mary M. Karanja
Summary: The East African rift system is formed above mantle upwellings and the formation of rifts is related to lithospheric thinning and magmatic activity. The amount of splitting varies spatially and the fast axes are predominantly parallel to the orientation of the rifts. Thick lithospheric modules have less splitting and different orientations, which may indicate mantle plume flow. Splitting rotates and increases in strength as it enters the rift zones, suggesting that the anisotropy is mainly present at shallow depths.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Correction
Geochemistry & Geophysics
Ekaterina Rojas-Kolomiets, Owen Jensen, Michael Bizimis, Gene Yogodzinski, Lukas Ackerman
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Robert W. Nicklas, Igor S. Puchtel, Ethan F. Baxter
Summary: Oxygen fugacity is a fundamental parameter for understanding redox processes in igneous systems. This study compares the Fe-XANES oxybarometry method with the V-in-olivine method for evaluating fO(2) in MORB lavas. The results show that the V-in-olivine method is not applicable to samples with low MgO content, and that the majority of Archean komatiite sources have lower fO(2) than modern MORB.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Chunfei Chen, Stephen F. Foley, Sebastian Tappe, Huange Ren, Lanping Feng, Yongsheng Liu
Summary: The volatile components CO2 and H2O play a major role in mantle melting and heterogeneity. In this study, Ca isotopes were used to trace the lithological heterogeneity in alkaline magmatic rocks. The results revealed the presence of K-richterite and carbonate components as the source of alkaline magmas with low delta 44/40Ca values. These findings highlight the importance of Ca isotopes as a robust tracer of lithological variation caused by volatiles in the Earth's upper mantle.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Timothee Jautzy, Gilles Rixhon, Regis Braucher, Romain Delunel, Pierre G. Valla, Laurent Schmitt, Aster Team
Summary: Although the current approach to estimate catchment-wide denudation rates using only 10Be concentrations has made significant progress in geomorphology, this study argues for the inclusion of 26Al measurements and testing of steady-state assumptions in slow eroding, formerly glaciated landscapes. The study conducted measurements of both 10Be and 26Al in stream sediments from the Vosges Massif in France and found that elevation, slope, channel steepness, and precipitation were the primary factors controlling denudation rates. The study also revealed a significant relationship between the extent of past glaciation and the cosmogenic (un-)steadiness in the stream sediments.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)
Article
Geochemistry & Geophysics
Erik van der Wiel, Douwe J. J. van Hinsbergen, Cedric Thieulot, Wim Spakman
Summary: Numerical models of Earth's mantle dynamics can predict the vigour and mixing of mantle flow, and the average slab sinking rates are an unexplored parameter that can provide intrinsic information on these characteristics. Through numerical experiments, it has been found that slab sinking rates are strongly correlated with mantle convection and mixing, and may explain geochemical observations from hotspot volcanoes.
EARTH AND PLANETARY SCIENCE LETTERS
(2024)