Article
Multidisciplinary Sciences
Jijun Wang, Xiao Zhou, Songlin Yu, Bingzhen Li, Yan Li
Summary: Ground radar interferometry technology, a new tool for active remote sensing, has been widely used for detecting various targets. In complex observation environments, meteorological disturbances significantly affect measurement accuracy. Analyzing the spatial distribution of meteorological disturbance phases and proposing correction methods can effectively improve radar observation accuracy.
Article
Geosciences, Multidisciplinary
Waqar Ali Zafar, Farhan Javed, Rizwan Ahmed, Muhsan Ehsan, Kamal Abdelrahman, Mohammed S. Fnais, Mansoor Aziz Qureshi
Summary: The Kalabagh strike-slip fault is part of the northwestern Himalayan foreland fold and thrust belt in Pakistan, characterized by right-lateral movement. Through the analysis of SAR interferometry data, it was found that the southern and northern segments of the fault exhibit aseismic creeping, while the central section does not. The presence of a thick salt layer over the decollement facilitates the creeping on this fault and also causes vertical deformations.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Environmental Sciences
Vassilis Sakkas
Summary: In this study, a combination of GNSS and InSAR data was used to model and characterize the source of the Mw6.9 earthquake that occurred north of Samos Island. Pre-seismic analysis showed an extensional regime in the NNE-SSW direction, while coseismic analysis revealed significant horizontal and vertical displacements in the epicentral region. The compiled interferometric maps indicated larger ground displacements in the western part of Samos, attenuating towards the eastern and southern parts.
Article
Remote Sensing
Tauri Tampuu, Jaan Praks, Ain Kull, Rivo Uiboupin, Tanel Tamm, Kaupo Voormansik
Summary: The study evaluates the use of Sentinel-1 interferometric SAR for monitoring peat extraction, demonstrating that temporal median coherence allows for detecting surface alterations related to harvesting activities. VV polarization is found to be more sensitive to changes compared to VH polarization. The study also shows the potential for estimating peat extraction intensity based on coherence, and proposes methods to distinguish different types of extraction areas and reduce the impact of rainfall-induced false positives.
INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION
(2021)
Article
Geochemistry & Geophysics
Akiko Takeo, Kiwamu Nishida, Hiroshi Aoyama, Motoko Ishise, Takeru Kai, Ryo Kurihara, Takuto Maeda, Yuta Mizutani, Yuki Nakashima, Shogo Nagahara, Xiaowen Wang, Lingling Ye, Takeshi Akuhara, Yosuke Aoki
Summary: By conducting a passive seismic campaign and analyzing ambient noise records, we measured the S-wave velocity structure beneath a lava dome, revealing a narrow and deep root of the dome and the impact of cracking on the velocity within the dome.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Chemistry, Multidisciplinary
Ilias Lazos, Ioannis Papanikolaou, Sotirios Sboras, Michael Foumelis, Christos Pikridas
Summary: The Strymon basin in Northern Greece, a geodynamically active region, hosts active faults. Through GNSS and InSAR techniques, researchers analyzed crustal deformation and found results consistent with palaeoseismological surveys and active fault mapping.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Multidisciplinary
Hiromi Kaji, Toru Takeshita
Summary: In this study, microstructural and microchemical analyses were conducted on deformation bands in the forearc fold belt of the Eocene Urahoro Group in northern Japan. These bands were found to have originated as phyllosilicate bands and transformed into cataclastic bands with increasing strain. In the cataclastic bands, sandstone grains were crushed and fractured, with the long axis of fractured grains aligning parallel to the deformation bands. The study also revealed that deformation bands played a significant role in weathering processes.
APPLIED SCIENCES-BASEL
(2022)
Article
Geochemistry & Geophysics
Natalia Poiata, Jean-Pierre Vilotte, Nikolai M. Shapiro, Mariano Supino, Kazushige Obara
Summary: Researchers in Shikoku, Japan, created a detailed catalog of low-frequency earthquakes (LFEs) over a four-year period using advanced automatic detection and location methods. They found complex and heterogeneous characteristics in the distribution and behavior of LFEs, which may be related to the complexity of subduction zone structure, stress evolution, and possible presence of fluids. High-resolution LFE catalogs can provide valuable information for understanding slow earthquake processes and preparing for large events in subduction zones.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
Feng Cheng, Andrew V. Zuza, Peter J. Haproff, Chen Wu, Christina Neudorf, Hong Chang, Xiangzhong Li, Bing Li
Summary: This study focuses on the structural framework of the central Qilian Shan of northeastern Tibet, investigating how plate convergence is accommodated by intracontinental strike-slip faulting and block rotation within a fold-thrust belt. The results suggest that right-slip faults play a role in accommodating block rotation and distributed crustal stretching, and are compatible with regional clockwise lithospheric flow.
JOURNAL OF THE GEOLOGICAL SOCIETY
(2021)
Article
Geosciences, Multidisciplinary
Anis Khalifeh-Soltani, Seyed Ahmad Alavi, Mohammad Reza Ghassemi, Mehdi Ganjiani, Reza Derakhshani
Summary: This study explores the interplay among sliding, buckling, and bending in the formation of fault-related folds, and finds that sliding parallel to layering and faults, in conjunction with buckling, are the predominant mechanisms in fault-related folding.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Virology
Masayuki Honda, Hiroyuki Asakura, Tatsuo Kanda, Yoshiko Somura, Tomotaka Ishii, Yoichiro Yamana, Tomohiro Kaneko, Taku Mizutani, Hiroshi Takahashi, Mariko Kumagawa, Reina Sasaki, Ryota Masuzaki, Shini Kanezawa, Kazushige Nirei, Hiroaki Yamagami, Naoki Matsumoto, Mami Nagashima, Takashi Chiba, Mitsuhiko Moriyama
Summary: An outbreak of acute hepatitis A virus (HAV) infection was observed among non-HIV-infected individuals, mainly males, in the northern part of Tokyo between 2018 and 2020. The study found that total bilirubin levels and platelet counts tended to be lower in men who have sex with men (MSM), while C-reactive protein (CRP) levels were higher in patients with acute liver failure (ALF). HAV isolates belonging to subgenotype IA/subgroup 13 (S13) clustered with isolates from an outbreak among MSM in Taiwan in 2015, suggesting potential utility of antivirals and vaccines for severe HAV infection treatment and prevention.
Article
Multidisciplinary Sciences
Wentao Xie, Matthias Lorenz, Friederike Poosch, Rupert Palme, Dietmar Zechner, Brigitte Vollmar, Eberhard Grambow, Daniel Strueder
Summary: By introducing a new lightweight PEEK chamber, this study successfully refined the dorsal skinfold chamber model, reducing animal distress and extending the observation time.
SCIENTIFIC REPORTS
(2022)
Article
Geosciences, Multidisciplinary
Mohammad R. Ghassemi, Mahasa Roustaei
Summary: Emergent salt diapirs are highly mobile geological objects that pose important questions for geologists and engineers. By studying the Anguru diapir using InSAR time-series data, it is found that there is recent activity and movement in the area.
JOURNAL OF THE GEOLOGICAL SOCIETY
(2021)
Article
Geosciences, Multidisciplinary
Pace Paolo, Fernando Calamita, Enrico Tavarnelli
Summary: This study documents the variation of fault-related inversion folds within curved thrust systems in the Central-Northern Apennines of Italy. The reconstruction of fold structures is based on geological field data and structural restoration of key balanced cross-sections, with additional constraints from panoramic views, geological field mapping, and structural analysis. The lateral variation from fault-bend to fault-propagation folding is attributed to the selective reactivation of precursor normal faults, which are preferentially located along the ramps of the curved thrust system. The space variability of these precursor faults is observed in curved thrust systems of different sizes, highlighting a scale-invariant phenomenon.
MARINE AND PETROLEUM GEOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Kai Huang, Lei Wu, Haifeng Zhao, Junyong Zhang, Yongshu Zhang, Ancheng Xiao, Yan Chen, Hanlin Chen
Summary: The study presents a detailed structural analysis of Cenozoic faults in the NW margin of the Qaidam Basin, identifying two sets of orthogonal faults with contrasting characteristics and linking their development to the transition from transpression to left lateral slip. The interplay between the two fault sets results in a more complicated evolution pattern of transpressional-dominated fold and thrust belts compared to contractional-dominated ones.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geochemistry & Geophysics
Takuya Nishimura
Summary: The study systematically examined slow slip events in central Japan and found significant differences in slip behavior along subduction zones. Many slow slip events can accommodate relative plate motion aseismically, with limited temporal correlations with other slow earthquakes and earthquake swarms.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2021)
Editorial Material
Geosciences, Multidisciplinary
Toru Matsuzawa, Ichiko Shimizu, Takuya Nishimura, Christopher J. Spiers, Junichi Nakajima, Tatsuhiko Kawamoto
EARTH PLANETS AND SPACE
(2021)
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
Geochemistry & Geophysics
J. Tago, V. M. Cruz-Atienza, C. Villafuerte, T. Nishimura, V Kostoglodov, J. Real, Y. Ito
Summary: ELADIN is a new static slip inversion strategy that efficiently handles plausible slip constraints by using a Gradient Projection Method. It reduces the model space, weights observations, and simultaneously determines regions subject to both stressing and relaxing slip regimes. Through careful regularization, it achieves reliable solutions for studying slow, aseismic slip interaction between tectonic plates.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Multidisciplinary Sciences
V. M. Cruz-Atienza, J. Tago, C. Villafuerte, M. Wei, R. Garza-Giron, L. A. Dominguez, V. Kostoglodov, T. Nishimura, S. I. Franco, J. Real, M. A. Santoyo, Y. Ito, E. Kazachkina
Summary: The study suggests that the devastating earthquakes in Mexico between 2017 and 2019 may be related to slow slip events. It shows how seismic and aseismic events are interrelated, with the Mw 8.2 intraslab earthquake of 8 September 2017 altering the mechanical properties of the plate interface and disrupting slow slip cycles at a regional scale.
NATURE COMMUNICATIONS
(2021)
Article
Geosciences, Multidisciplinary
Yutaro Okada, Takuya Nishimura, Takao Tabei, Takeshi Matsushima, Hitoshi Hirose
Summary: This study uses GNSS data and a developed detection method to detect short-term slow slip events (S-SSEs) in the Nankai subduction zone and quantitatively study their regional variation in duration. The method extracts S-SSE signals and enhances them for duration estimation using correlation coefficients and stacking of GNSS time series. The study provides geodetic evidence for the synchronization of S-SSEs and other seismic phenomena in offshore Kyushu and identifies significant regional differences in slip rate.
EARTH PLANETS AND SPACE
(2022)
Article
Geosciences, Multidisciplinary
Tha Zin Htet Tin, Takuya Nishimura, Manabu Hashimoto, Eric O. Lindsey, Lin Thu Aung, Saw Myat Min, Myo Thant
Summary: The study analyzed crustal deformation along the central and southern parts of the Sagaing fault in Myanmar using GNSS data. The estimated slip rate is higher in the central part (-23-24 mm/yr) compared to the southern part (around 16 mm/yr). The potential magnitude of earthquakes for each segment is estimated to be around Mw 7.3-7.4.
JOURNAL OF ASIAN EARTH SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Takuya Nishimura
Summary: This study developed a regional likelihood model for crustal earthquakes in southwest Japan, utilizing geodetic strain-rate data. Different conversion equations, seismogenic thicknesses, and rigidities were used to validate the models, which showed better predictive skill in the Niigata-Kobe Tectonic Zone and central Kyushu. The study concluded that the proposed forecast model based on geodetic data can enhance the regional likelihood model for crustal earthquakes in Japan when combined with other forecast models based on active faults and seismicity.
EARTH PLANETS AND SPACE
(2022)
Article
Geochemistry & Geophysics
Ichiro Kawasaki, Hiroshi Ishii, Yasuhiro Asai, Takuya Nishimura
Summary: The ultrabroadband seismograms recorded by the global navigation satellite system and stress meter provided valuable insights into the wave propagation phenomena associated with the 2011 Tohoku earthquake. These recordings allowed us to track unique phases and understand the mechanisms behind the tsunami and resonance phenomenon.
JOURNAL OF SEISMOLOGY
(2023)
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
Geography, Physical
Yukitoshi Fukahata, Tomohisa Okazaki, Takuya Nishimura
Summary: This paper introduces a method based on basis function expansion with Akaike's Bayesian information criterion to estimate strain-rate fields from geodetic data. The method is applied to GNSS data in Japan, and strain-rate fields for different time periods are obtained. The deformation is explained using the framework of inter-arc and intra-arc deformation.
JOURNAL OF GEOGRAPHY-CHIGAKU ZASSHI
(2022)
Article
Multidisciplinary Sciences
Takuya Nishimura, Yoshihiro Hiramatsu, Yusaku Ohta
Summary: Since November 30, 2020, there has been an intense seismic swarm and transient deformation in the Noto Peninsula, central Japan. Through the analysis of multiple GNSS observation networks, earthquake hypocenters, and tectonic settings, we found that the deformation pattern over 2 years shows horizontal inflation and uplift of up to 70 mm around the source of the earthquake swarm. The upwelling fluid spread through an existing shallow-dipping permeable fault zone at a depth of 16 km, triggering a long-lasting sub-meter aseismic slip and intense earthquake swarms.
SCIENTIFIC REPORTS
(2023)
Article
Geosciences, Multidisciplinary
Hitoshi Hirose, Takeshi Matsushima, Takao Tabei, Takuya Nishimura
Summary: Slow slip events (SSEs) lasting for approximately 1 year occur every 6-8 years around the Bungo Channel in the southwest Japan subduction zone. The spatial and temporal relationship between the slip process and other phenomena such as tectonic tremors and SSEs is not well understood. In this study, using data from GNSS stations installed around the Bungo Channel and Hyuganada, the slip evolutions of two SSEs in 2018-2019 and 2015-2016 were estimated, revealing the overlap between the major SSE and the deep episodic tremor and slip (ETS) zone.
EARTH PLANETS AND SPACE
(2023)
Article
Geochemistry & Geophysics
Tomoaki Nishikawa, Takuya Nishimura
Summary: Research has found that slow slip events (SSEs) at subduction zone plate boundaries can trigger earthquake swarms and megathrust earthquakes. The current statistical models do not explicitly consider the seismicity-triggering effect of SSEs, resulting in failed earthquake predictions. In this study, a new statistical model named the SSE-modulated ETAS model was constructed by incorporating SSE moment rates into the original ETAS model. Application of this new model to SSEs and M 2.5 or greater earthquakes in the Hikurangi Trench, New Zealand showed significant improvement compared to the original model.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geosciences, Multidisciplinary
Yutaro Okada, Takuya Nishimura
Summary: In southcentral Alaska, 31 short-term slow slip events (S-SSEs) were detected using Global Navigation Satellite System data. These events mainly occurred at a depth of 35 to 45 km, correlating with the down-dip extension of the 1964 Alaska earthquake and the subducting Yakutat microplate. The findings highlight the importance of short-term slow slip events for understanding interplate slip kinematics in this region.
GEOPHYSICAL RESEARCH LETTERS
(2023)
