Article
Multidisciplinary Sciences
Fabian Limberger, Georg Ruempker, Michael Lindenfeld, Hagen Deckert
Summary: In order to address the impact of ground vibrations caused by wind turbines on seismic observations, we have developed the first numerical model to predict the seismic wavefield generated by wind farms, taking into account factors such as wavefield interferences, surface topography, and attenuation.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Cheng-Horng Lin, Min-Hung Shih, Ya-Chuan Lai
Summary: This study reveals the first detection of seismic scattering obstacles in the mantle wedge beneath active volcanoes, providing insights into the potential association between mantle wedge diapirs and magma generation. The findings suggest that the arc magma may not only be triggered by fluids or melts from subducted slabs, but also by physically mixed melange diapirs in the mantle wedge.
SCIENTIFIC REPORTS
(2021)
Article
Geochemistry & Geophysics
Stefano Parolai, Giovanna Laurenzano, Marco Garbin
Summary: By analyzing seismic noise, we can estimate the cross-coupling effects among the three components of ground motion caused by heterogeneities in the underground structure. The results highlight the significance of these effects, which are influenced by lateral variations in the bedrock surface and heterogeneities within the sedimentary cover.
SEISMOLOGICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Tiaren Garcia-Perez, Ana M. G. Ferreira, Gonzalo Yanez, Pablo Iturrieta, Jose Cembrano
Summary: This study investigates the effects of topography and basins on seismic wave amplification following an earthquake, showing that both factors can significantly increase the amplitude and duration of ground motion. While there is good agreement between real and synthetic seismic waveforms at lower frequencies, the fit deteriorates at higher frequencies due to unresolved 3-D velocity heterogeneity.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Yujin Liu, Yubo Yue, Yi Luo, Youming Li
Summary: Train traffic, especially high-speed trains, is recognized as a powerful noise source for subsurface imaging and monitoring. This study investigates the effects of train traffic characteristics on seismic interferometry, finding that using high-speed train traffic noise can generate crosstalk that is effectively attenuated by stacking interferometric results. The study demonstrates that retrieved surface waves from this method can be used to estimate near-surface velocities.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Jianlu Wu, Bing Zhou, Stewart Greenhalgh, Youcef Bouzidi, Zhiming Zhang
Summary: The paper presents and compares two new methods for calculating the reflection and transmission coefficients of various waves at a flat interface between viscoelastic anisotropic half-spaces. The methods provide accurate results and offer practical solutions for studying wave behavior at interfaces.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Ruei-Jiun Hung, Kuo-Fong Ma, Teh-Ru Alex Song, Yen-Yu Lin, Matthew Weingarten
Summary: This study examines the long-term anisotropy in the fault zone after the 1999 Chi-Chi earthquake using seismic data from the Taiwan Chelungpu-fault Drilling Project. The results show weak anisotropy in the shallow crust and fault healing over time, as well as seasonal variations in anisotropy correlated with rainfall events.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geosciences, Multidisciplinary
Andrew T. Lin, Chih-Cheng Yang, Ming-Huei Wang, Jong-Chang Wu
Summary: Oligocene-Miocene sediments in the Taiwan region were studied using boreholes and reflection seismic data, revealing 16 sequences grouped into four sets. Sequence sets B and C show uniform deposition, while sequence sets A and D were influenced by extensional tectonics, forming fault-bounded troughs.
JOURNAL OF ASIAN EARTH SCIENCES
(2021)
Article
Physics, Multidisciplinary
Qifeng Jiang, Wei Wei, Hongtai Xu, Tengchao Dong
Summary: Topography has a significant effect on ground motions, and its quantification is important for seismic hazard prevention. This study established numerical models and used neural network methods to analyze the variables that influence topographic amplification factors. Key findings include the importance of altitude, slope, aspect, and frequency, and the identification of two input variable combinations that achieve good performance.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Geochemistry & Geophysics
Kunxi Wang, Tianyue Hu, Shangxu Wang
Summary: An iterative inversion method based on the unsupervised deep neural network is proposed to deblend simultaneous source data, effectively suppressing crosstalk noise and protecting weak effective signals, achieving good effectiveness in separating simultaneous source data.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geosciences, Multidisciplinary
O. G. Sanford, N. Schofield, R. W. Hobbs, R. J. Brown
Summary: Imaging subsurface igneous sill complexes is a seismic challenge due to a lack of understanding of the interaction between geological structures and the seismic wavefield. This study uses high-resolution seismic modeling to show that only a small amount of energy passes through the sills to reach the target reflector. Factors limiting energy transmission include internal multiples, converted modes, and leaky guided waves within the sills. Further research should focus on optimizing the processing of seismic data to improve imaging around sill complexes.
MARINE AND PETROLEUM GEOLOGY
(2023)
Article
Multidisciplinary Sciences
Christopher J. Banks, Francisco Mir Calafat, Andrew G. P. Shaw, Helen M. Snaith, Christine P. Gommenginger, Jerome Bouffard
Summary: The first European ice mission, CryoSat-2, launched by the European Space Agency in 2010, successfully achieved its primary objectives of measuring sea ice thickness and ice sheets. The data collected by CryoSat-2 was recognized for its value over global oceans, leading to the development of operational products through the CryoSat Ocean Processor (COP). The unique orbit of CryoSat-2 allowed for denser coverage of sample points compared to other satellite altimeters.
Article
Geochemistry & Geophysics
Bjorn Ursin, Nathalie Favretto-Cristini, Paul Cristini
Summary: Seismic data recorded in complex geological environments require compensation for geometrical spreading before AVO/AVA analysis, and interface effects should also be compensated. 3-D numerical simulations validate analytical derivations, showing that interface curvature has a significant impact on reflected events. This highlights the importance of considering interface effects in AVA/AVO analysis to avoid misinterpretation.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Vladimir Leviant, Naum Marmalevsky, Igor Kvasov, Polina Stognii, Igor Petrov
Summary: This study focuses on evaluating the infill type of fractured reservoirs, using numerical modeling of seismic responses and AVO gradient analysis to reveal previously unknown properties of seismic responses from fractured reservoirs, and developing quantitative criteria for recognition of fracture infill type.
Article
Energy & Fuels
Erkang Zhou, Tianqi Zhai, Jianbo Zhu
Summary: Understanding wave propagation behavior in rock masses under different temperatures and geological conditions is crucial for evaluating the stability and safety of deep rock engineering projects. This study investigated the response and mechanism of ultrasonic waves in granites after thermal treatment. The results showed that heating temperature and grain size had a combined impact on wave propagation in the tested granites. The crack evolution was identified as the main reason for the seismic response of thermally treated granites. A damage factor and optimal wave indicators were proposed to evaluate the deterioration of granites at different damage stages.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Geochemistry & Geophysics
Wenjie Lei, Youyi Ruan, Ebru Bozdag, Daniel Peter, Matthieu Lefebvre, Dimitri Komatitsch, Jeroen Tromp, Judith Hill, Norbert Podhorszki, David Pugmire
GEOPHYSICAL JOURNAL INTERNATIONAL
(2020)
Article
Geochemistry & Geophysics
Leah Langer, Thea Ragon, Anthony Sladen, Jeroen Tromp
Article
Geochemistry & Geophysics
Lucia Gualtieri, Etienne Bachmann, Frederik J. Simons, Jeroen Tromp
Summary: Secondary microseisms are ambient noise vibrations caused by ocean activity and dominate seismic records worldwide at periods between 3 and 10 seconds. Using a spectral-element method for global-scale modeling, Love waves naturally emerge due to seismic wavefield interaction with Earth heterogeneity, particularly in the mantle. The distribution of surface sources, topography, and bathymetry are crucial for understanding the generation and propagation of Love waves in secondary microseisms.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Astronomy & Astrophysics
Samarth G. Kashyap, Srijan Bharati Das, Shravan M. Hanasoge, Martin F. Woodard, Jeroen Tromp
Summary: Normal-mode helioseismic data analysis uses observed solar oscillation spectra to infer perturbations in the solar interior due to global and local-scale flows and structural asphericity. Differential rotation is the dominant global-scale axisymmetric perturbation, primarily constrained using measurements of frequency splittings via a-coefficients. However, analyzing eigenfunction corrections that respect cross-coupling of modes across multiplets provides a more accurate approach, although it results in a wider spread of a-coefficients compared to frequency splittings. The study demonstrates the effectiveness of Bayesian statistics in inferring a-coefficients due to differential rotation from cross-spectra for modes with angular degrees l = 50-291, with the inferred values close to frequency-splitting values for l > 200 but failing for l < 50 due to insensitivity of the measurement. The results highlight mode-coupling as an important helioseismic technique for inferring internal solar structure and dynamics.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2021)
Article
Geochemistry & Geophysics
Yanadet Sripanich, Ivan Vasconcelos, Jeroen Tromp, Jeannot Trampert
Summary: This study emphasizes the importance of considering different definitions of stress and their effects on seismic quantities in seismic wave propagation. By revisiting the fundamental theoretical foundation, the study investigates the connection between stress and variations in elastic moduli, using both traditional elasticity tensor and adiabatic pressure derivatives. Additionally, the study explores the connection with micromechanical structures and their practical applications.
Article
Geochemistry & Geophysics
Qiancheng Liu, Stephen Beller, Wenjie Lei, Daniel Peter, Jeroen Tromp
Summary: In this study, the BFGS algorithm was modified to perform uncertainty quantification for large-scale applications, with the combination of random singular value decomposition for a low-rank approximation of the inverse Hessian. Different initial, diagonal Hessian matrices were used as pre-conditioners in elastic FWI applications to compare performance.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Acoustics
Masaru Nagaso, Joseph Moysan, Christian Lhuillier, Dimitri Komatitsch
Summary: This study utilized a four-dimensional numerical simulation to calculate wave propagation in thermal fluctuating liquid metal, demonstrating that ultrasonic measurements can track thermal-hydraulic fluctuations in opaque liquids with high sensitivity. A new measurement index, CTFI, was defined to analyze medium fluctuations along the wave path, showing good correlation with acoustic measurements and providing insights for practical industrial applications.
Article
Geochemistry & Geophysics
Lucas Sawade, Stephen Beller, Wenjie Lei, Jeroen Tromp
Summary: The global centroid-moment tensor (GCMT) project has determined earthquake location and source parameters using a 1-D reference earth model. However, a new methodology using a 3-D earth model has revealed biases in the standard approach. This paper presents a revised catalogue of centroid-moment tensors (CMT) computed using a 3-D model, which shows significant differences from the GCMT catalogue.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Leah Langer, Stephen Beller, Evan Hirakawa, Jeroen Tromp
Summary: Earthquakes often occur in regions with complex material structure, but most co-seismic modeling studies use simplified, homogeneous elastic structures, which may introduce bias into estimated slip models. This study investigates the impact of 3-D elastic structure on forward models of co-seismic surface deformation using a synthetic model of a sedimentary basin.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Chenxing Luo, Jeroen Tromp, Renata M. Wentzcovitch
Summary: This study reviews the thermodynamic definition of the third-order elastic tensor and proposes using an effective third-order elastic tensor. An explicit expression for the effective third-order elastic tensor is given and verified. By extending the ab initio approach, we evaluate the strain-induced changes in SOECs and pressure derivatives of SOECs, and confirm the validity of our theory through comparisons with numerically calculated values.
Meeting Abstract
Obstetrics & Gynecology
M. Van den Berg, C. Beerendonk, S. Kaal, C. Mandigers, T. Schuurman, J. Tol, J. Tromp, M. Van der Vorst, D. Braat, R. Hermens
HUMAN REPRODUCTION
(2022)
Article
Geosciences, Multidisciplinary
Tsung-Chih Chi, Young-Fo Chang, Bor-Shouh Huang
Summary: The receiver function method was used to analyze teleseismic waveforms recorded in Taiwan in order to understand the crustal structure. By incorporating Common Conversion Point (CCP) stacking, the research revealed the features of the collision boundary and Moho discontinuities. Results showed that the Moho depths deepen from north to south in northern Taiwan, while the crust in the west is thin and flat, and the east exhibits lithospheric deformation and mountain root formation.
Article
Environmental Sciences
Federica Magnoni, Emanuele Casarotti, Dimitri Komatitsch, Raffaele Di Stefano, Maria Grazia Ciaccio, Carl Tape, Daniele Melini, Alberto Michelini, Antonio Piersanti, Jeroen Tromp
Summary: Through ground motion recordings and seismic tomography, we have gained a more accurate understanding of the subsurface structure of the Italian lithosphere. The research reveals the distribution of fluids and gases in correlation with seismic activity, supports the hypothesis of a deep reservoir feeding the Mt. Etna volcano, and uncovers the complex lithosphere and tectonic evolution of the Adriatic plate.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)
Article
Geochemistry & Geophysics
Qiancheng Liu, Stephen Beller, Wenjie Lei, Daniel Peter, Jeroen Tromp
Summary: Full-waveform inversion is crucial in mapping geophysical subsurface structures, but lacks proper uncertainty quantification in current applications. This study enhances the BFGS algorithm for uncertainty quantification in large-scale applications, combining it with randomized singular value decomposition to obtain a low-rank approximation of the inverse Hessian. This approach is efficient and memory-affordable, demonstrating applicability for large-scale FWI and uncertainty quantification.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)