Review
Geochemistry & Geophysics
Dapeng Zhao, Jian Wang, Zhouchuan Huang, Xin Liu
Summary: Recent studies have provided insights into the seismic structure and subduction dynamics of the western Japan arc, revealing details about the subduction of the Pacific and Philippine Sea slabs, anomalies in the crust and mantle wedge, and the nucleation of large megathrust earthquakes. These findings underscore the importance of structural heterogeneities in controlling seismic activities in the region.
Article
Environmental Sciences
A. Fathian, S. Atzori, H. Nazari, K. Reicherter, S. Salvi, N. Svigkas, M. Tatar, C. Tolomei, F. Yaminifard
Summary: The largest earthquake in the Zagros Mountains struck the city of Azgeleh on the Iran-Iraq border on 12 November 2017, followed by intense seismic activity. A total of 1069 events were relocated by utilizing the double-difference earthquake location technique, revealing linear alignments of events in at least four notable clusters. The seismic sequence from 2017-2018 involved significant earthquakes in various clusters, reflecting the complex fault structures in the region.
REMOTE SENSING OF ENVIRONMENT
(2021)
Article
Geochemistry & Geophysics
Ao Zheng, Xiangwei Yu, Jiaqi Qian, Xiaoge Liu, Wenbo Zhang, Xiaofei Chen, Wenbin Xu
Summary: The 2021 Mw 7.4 Maduo earthquake occurred in the most seismically active block of the Tibetan Plateau. The source rupture propagated bilaterally on a splay fault geometry with sinistral slips dominating and several asperities present. The seismic hazard of subsidiary faults, such as Maduo-Gande and Tibet Dagou-Changmahe faults, should not be neglected.
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
Oceanography
Y. Wang, N. Zamora, M. Quiroz, K. Satake, R. Cienfuegos
Summary: This study focuses on investigating the resonance characteristics of trans-Pacific tsunami events in bays and continental shelves of Japan, revealing that regional seafloor topography is the key factor controlling resonance behaviors, while period components generated at far-field tsunami sources are more noticeable on signals recorded at offshore stations.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Geochemistry & Geophysics
Wenhao Xu, Jinghuai Gao, Lingling Wang, Yajun Tian, Jianfeng Qiu, Xiudi Jiang, Daxing Wang
Summary: This paper proposes a new algorithm called compact smoothness and relative sparsity (CSRS) algorithm for wavelet and reflectivity inversion (WRI) in seismic data processing. The algorithm introduces normalized constraints and regularization to overcome the ill-posedness of WRI inversion and improve the lateral continuity of reflectivities. It also presents an efficient algorithm for solving the optimization problem of WRI by dividing it into reflectivity inversion and wavelet inversion subproblems.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Engineering, Geological
Katsuichiro Goda, Jeremy Rimando, Alexander L. Peace, Navid Sirous, Philippe Rosset, Luc Chouinard
Summary: Earthquakes in the Western Quebec seismic zone in eastern Canada pose significant risks to residents, as most houses are not built to modern seismic standards and homeowners do not purchase earthquake insurance. To quantify the financial risks, regional earthquake catastrophe models are developed using up-to-date hazard, exposure, and vulnerability information. The models consider a comprehensive list of seismic events and critical earthquake scenarios based on the latest geological data in the region. The results show that regional seismic losses could reach billions of dollars if a moderate-to-large earthquake occurs near urban centers such as Montreal and Ottawa. These loss estimates are useful for informing earthquake risk management strategies and policies.
GEORISK-ASSESSMENT AND MANAGEMENT OF RISK FOR ENGINEERED SYSTEMS AND GEOHAZARDS
(2023)
Article
Geosciences, Multidisciplinary
David R. R. Shelly, Robert J. J. Skoumal, Jeanne L. L. Hardebeck
Summary: In August 2020, a seismic sequence began in the Maacama fault zone in northern California, leading to questions about its connection with a larger fault. Through various seismic analysis techniques, including event detection, relocation, and focal mechanisms, the researchers investigated the faulting geometry and its impact on seismic activity. They discovered that the sequence originated from a right-lateral fault, likely a section of the Maacama Fault, but also activated numerous left-lateral conjugate faults, forming a fracture mesh consistent with fluid-induced faulting and earthquake swarms seen elsewhere.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Shunsuke Sugimura, Takeshi Nishimura, Giorgio Lacanna, Denis Legrand, Sebastien Valade, Maurizio Ripepe
Summary: Seismic waves excited by small Strombolian explosions at Stromboli volcano in Italy provide insights into the source process of volcanic explosions. The analysis of seismic signals reveals that the source of explosions moves towards the active crater before the onset of an explosion, reflecting the migration of gas-rich magma within the shallow reservoir system. This study highlights the importance of continuous monitoring of seismic activity to understand the dynamics of volcanic eruptions.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
Jianyong Song, Zhifang Yang, Hong Cao, Weiguang He, Wenyong Pan, Meng Li, Na Tian
Summary: Full waveform inversion is a method used to reconstruct subsurface structures by matching synthetic and observed waveforms. In this study, a combinatory inversion strategy based on seismic events is proposed to address the challenges caused by inaccurate source wavelets and model artifacts. The strategy incorporates Gaussian time windows and the optimal transport function to improve the accuracy of the inversion results. The effectiveness of the strategy is demonstrated through synthetic experiments and real-land seismic data inversion.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Engineering, Geological
Hamed Javdanian, Ali Heidari, Jalil Raeisi
Summary: The study decomposed strong ground motion records using wavelet transform with denoising and downsampling methods. Evaluation of frequency content changes during the decomposition process showed reasonable outcomes up to the third level, with denoising-based decomposed records offering better performance in dynamic analysis.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2021)
Article
Geochemistry & Geophysics
Yijun Yuan, Yingcai Li, Shichang Zhou
Summary: A new deconvolution method based on a multichannel statistical principle has been developed to address the noise effect on deconvolution operators and improve the resolution of seismic signals. The method involves calculating autocorrelation using a multichannel statistical strategy and adopting a local fitting technique to approximate the seismic wavelet's autocorrelation. Tests on synthetic data and real land seismic data show the effectiveness of the proposed method in increasing seismic signal resolution.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2021)
Article
Geochemistry & Geophysics
Christian Poppeliers, Leiph Preston
Summary: The uncertainty in earth models can lead to unpredictable biases in the amplitude of estimated seismic source functions, primarily manifested in the reduction of the amplitude of first-arriving seismic energy which is proportional to the magnitude of the stochastic heterogeneities.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Acoustics
Sahar Golestaneh Zadeh, Majid Amin Afshar
Summary: This research introduces the intermittent wavelet-based identification technique and pole assignment control to overcome the effect of dynamic characteristics changes on control force calculation. Experimental results show that the proposed adapted pole assignment method performs better in reducing damaged structure response compared to other control methods.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Geochemistry & Geophysics
Xiao Chen, Zhaoyun Zong, Yinghao Zuo
Summary: Young's modulus and the Poisson ratio are important parameters for shale reservoir identification and oil and gas detection. The broadband inversion approach combines seismic ultralow-frequency information with inversion results in the complex frequency domain, improving the stability, reliability, and resolution of the inversion. However, current amplitude variation with offset (AVO) inversions mostly rely on linear approximations, and there are few exact nonlinear or broadband inversion methods. We propose a new exact reflection coefficient equation based on the Zoeppritz equation for the inversion of Young's modulus, Poisson ratio, and density in the broadband complex domain. This method provides a theoretical basis for evaluating reservoir brittleness and compressibility, as well as a new approach for shale gas reservoir prediction and sweet spot identification. The accuracy and rationality of this method are validated using synthetic and field data examples.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)