Article
Geochemistry & Geophysics
Miroslav Hallo, Walter Imperatori, Francesco Panzera, Donat Faeh
Summary: The physical properties of near-surface soil and rock layers are crucial in seismic site effects analysis, and can be inferred through non-linear inversion techniques. An alternative inversion technique within the Bayesian framework allows for the inference of posterior probability density in the model space.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
I Gaudot, E. Beucler, A. Mocquet, M. Drilleau, M. Haugmard, M. Bonnin, G. Aertgeerts, D. Leparoux
Summary: This study presents a 3-D seismic tomographic model of western France and surrounding regions, revealing the crustal structure in detail. Using an unconventional approach with 55 broad-band seismometers, a V-S model with lateral resolution of 75 km was constructed, providing insights into both shallow and deep crustal features in the area.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geosciences, Multidisciplinary
Melanie Drilleau, Eric Beucler, Jing Shi, Brigitte Knapmeyer-Endrun, Raphael F. Garcia, Veronique Ansan, Doyeon Kim, Philippe Lognonne, William B. Banerdt
Summary: This study measures the group velocity dispersion of surface waves generated by meteoroid impacts on Mars and provides insights into the crustal structure of the planet. The results reveal a four-layer model for the Martian crust near the InSight landing site, with a shallow low-velocity layer approximately 1.2 km thick.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Giulio Vignoli, Julien Guillemoteau, Jeniffer Barreto, Matteo Rossi
Summary: The analysis of surface wave dispersion curves is crucial for inferring the vertical distribution of shear wave velocity, with discussions on regularization strategies and the effectiveness of sparse reconstructions. The estimation of the depth of investigation using sensitivity kernels and the reliability of this estimation are also discussed in the presence of sharp boundaries.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Shufan Hu, Yonghui Zhao, Laura Valentina Socco, Shuangcheng Ge
Summary: The multiscale window analysis of surface waves (MWASW) method allows for a more accurate retrieval of subsurface shear wave velocity models, achieving higher lateral resolution of shallow structures and average information at greater depths. By inverting dispersion data extracted from different spatial windows, the MWASW method integrates subsurface information at different depth ranges and lateral extensions, providing a more realistic structural image.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Ivan Cabrera-Perez, Luca D'Auria, Jean Soubestre, Jose Barrancos, German D. Padilla, Nemesio M. Perez
Summary: In this work, an innovative technique for Ambient noise tomography based on nonlinear multiscale inversions is proposed, which shows improvement compared to conventional inversion schemes when ray path density is low. Additionally, no expensive computational resources are required for this technique, making it suitable for small-scale industrial applications, especially in geothermal exploration.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Enci Wang, Martyn Unsworth
Summary: This paper presents the first detailed 3-D study of the Alberta basement using the magnetotelluric (MT) method. It identifies multiple conductors in the crust and upper mantle, relating them to past tectonic events and kimberlite magmatism. The study also provides insights into the depth of the lithosphere-asthenosphere boundary and the characteristics of specific geological features in Alberta.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Omid Bagherpur Mojaver, Fiona Darbyshire, Riddhi Dave
Summary: The study reveals significant variations in seismic velocities across different tectonic zones, with no simple relation found between lithospheric thicknesses and ages. The lithosphere-asthenosphere boundary in the study area is located at depths of 70-120 km, with the thickest and fastest lithosphere beneath New Brunswick.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Graca Silveira, Nuno Afonso Dias, Sergey Kiselev, Eleonore Stutzmann, Susana Custodio, Martin Schimmel
Summary: This study presents a new high-resolution three-dimensional shear wave velocity model of the crust and uppermost mantle in Portugal. The model contributes to a better understanding of the seismicity and geological structures in Portugal.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Mohsen Kazemnia Kakhki, Ahmadreza Mokhtari, Webe Joao Mansur, Vincenzo Del Gaudio
Summary: In this paper, a novel time-frequency polarization filter based on three-component sparse adaptive S transform (3C-SAST) is proposed, which demonstrates high efficiency and flexibility in seismic surface wave separation.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Yingwei Yan, Xiaofei Chen, Nan Huai, Jianbo Guan
Summary: This paper introduces a staging strategy for the inversion of multimodal surface wave dispersion curves and proposes an inversion method based on pattern search and Kuhn-Munkres algorithm. Synthetic reconstruction tests confirm the effectiveness of this method and it is further validated through the analysis of actual data sets.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
L. A. Ermert, K. Sager, T. Nissen-Meyer, A. Fichtner
Summary: The method developed in the study effectively constrained the global source distribution of the Earth's hum, with dominant sources in the Southern Hemisphere during winter and exceptions in the Izu-Bonin-Mariana arc. Strong hum sources were found to be associated with coastlines or bathymetric highs. The practical feasibility of frequency-dependent noise source inversion was demonstrated, potentially improving full-waveform ambient noise inversions and enhancing our understanding of noise generation physics.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Jeremy M. Gosselin, Pascal Audet, Andrew J. Schaeffer, Fiona A. Darbyshire, Clement Esteve
Summary: Surface wave tomography is a valuable tool for constraining azimuthal anisotropy at regional scales, but the sparse and uneven coverage of dispersion measurements pose challenges in uncertainty estimation. A Bayesian trans-dimensional inversion approach is used in this paper to better model azimuthal anisotropy using surface wave dispersion data, with a focus on considering data errors and avoiding subjective model regularization. The results provide insights into the structural context of tectonic dynamics in northern Cascadia and Haida Gwaii, highlighting the importance of considering azimuthal anisotropy in tomographic inversions for understanding seismic and tsunami hazards.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Lingli Gao, Yudi Pan, Andreas Rieder, Thomas Bohlen, Weijian Mao
Summary: Full-waveform inversion (FWI) has been proven to be effective for high-resolution imaging of the shallow subsurface. In this study, the advantages of Gauss-Newton (GN) viscoelastic FWI over conventional FWI with a conjugate gradient optimization method are demonstrated using synthetic examples. The potential of 2-D viscoelastic FWI for high-resolution hydrogeological characterization is also investigated.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Lingli Gao, Yudi Pan, Andreas Rieder, Thomas Bohlen
Summary: The study applies a pre-conditioned truncated Newton (PTN) method to shallow-seismic FWI for simultaneous inversion of multiparameter near-surface models. Evaluation of scattered wavefields caused by different parameters and the performance of the PTN method in Rayleigh wave FWI demonstrate its effectiveness in mitigating cross-talk and improving resolution, especially for weak parameters like attenuation and density.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geography, Physical
Michael G. Baker, Richard C. Aster, Douglas A. Wiens, Andrew Nyblade, Peter D. Bromirski, Peter Gerstoft, Ralph A. Stephen
Summary: Observations of teleseismic earthquakes using broadband seismometers on the Ross Ice Shelf reveal seasonal and geographic variations in signal-to-noise ratios, accurate estimation of ice and water layer thicknesses, and observations consistent with theoretically predicted phenomena, suggesting that teleseismic coda can be utilized for passive imaging of sub-shelf Earth structure.
JOURNAL OF GLACIOLOGY
(2021)
Article
Geochemistry & Geophysics
Erica M. Lucas, Andrew A. Nyblade, Andrew J. Lloyd, Richard C. Aster, Douglas A. Wiens, John Paul O'Donnell, Graham W. Stuart, Terry J. Wilson, Ian W. D. Dalziel, J. Paul Winberry, Audrey D. Huerta
Summary: A total of 117 previously undetected seismic events in central West Antarctica have been identified, originating from glacial, tectonic, and volcanic processes. The uppermost portion of the mantle beneath central West Antarctica shows laterally variable structure, with implications for geothermal heat flux and glacial isostatic adjustment spatial patterns. The discoveries in this study have significant implications for understanding the dynamics and evolution of the West Antarctic Ice Sheet.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2021)
Article
Geochemistry & Geophysics
E. Tsang-Hin-Sun, M. Evain, J. Julia, G. Lamarque, P. Schnurle
Summary: This study investigates the seismic structure and anisotropy in the crust beneath Madagascar and southeastern Africa using receiver functions. The results reveal significant azimuthally varying signals within the upper crust of the region, with crustal anisotropy dominating in some stations and dipping isotropic contrasts dominant in others. The complex backazimuth harmonics suggest a combination of different sources of anisotropy at shallow depth, reflecting variations in the lithospheric structure and local inherited structural heterogeneities.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
Richard C. Aster, Bradley P. Lipovsky, Hank M. Cole, Peter D. Bromirski, Peter Gerstoft, Andrew Nyblade, Douglas A. Wiens, Ralph Stephen
Summary: The interaction between ocean swell and Antarctic ice shelves results in sustained gravity-elastic perturbations with deformation amplitudes near the ice front. These perturbations are most active during the austral summer, with dominant frequency content between 0.5 and 20 Hz and highly repetitive waveforms.
SEISMOLOGICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Michael E. Pasyanos, Andrea Chiang
Summary: Moment tensor solutions are calculated for U.S. underground nuclear tests and forms an extensive database for evaluating monitoring tasks and testing explosion monitoring methodologies.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2022)
Article
Geosciences, Multidisciplinary
Gaohua Zhu, Douglas A. Wiens, Hongfeng Yang, Jian Lin, Min Xu, Qingyu You
Summary: Seismic imaging methods were used to study the SV-wave velocity structure near the Southern Mariana Trench, revealing extensive mantle hydration of the incoming plate and differences in forearc serpentinization between southern and central Mariana.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
Ana M. Nemocon, Jordi Julia, Xavier Garcia
Summary: The crust is typically 34-38 km thick under the western Province and 43-46 km thick under the northern craton. No apparent crustal thinning is observed under the Araripe Basin, due to the presence of a relatively thick lowermost crust. Our findings also suggest the presence of a mid-lithospheric discontinuity and lithosphere-asthenosphere boundary under the Araripe Basin.
Article
Geochemistry & Geophysics
M. F. Doring, J. Julia, M. Evain
Summary: The crustal structure of the Reconcavo-Tucano basin in NE Brazil was investigated, revealing that the crust is over 40 km thick beneath the basin and contains a layer of high velocity material. Comparisons with neighboring regions show that the crust in the basin is thicker and has higher lower crustal velocities. The results support models of basin formation involving pure shear extension in the lower crust.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Michael E. Pasyanos
Summary: Seismic moment, a measurable quantity of seismic sources, is used to estimate the yield of explosions. This study introduces a new method that utilizes a full moment tensor solution and an explosion source model to estimate the moment-to-yield ratio. The results obtained from applying this method to North Korean nuclear explosions align with other yield estimates.
SEISMOLOGICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Zheng Tang, Jordi Julia, P. Martin Mai, Walter D. Mooney, Yanqiang Wu
Summary: A high-resolution 3D crustal and upper-mantle shear-wave velocity model of Northeast China is established through joint inversion of receiver functions and fundamental-mode Rayleigh wave phase velocities, providing insights into the internal structure of the Earth.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geosciences, Multidisciplinary
Keehoon Kim, Michael E. E. Pasyanos
Summary: This study accurately estimates the size of the 2020 Beirut explosion using the inversion technique of infrasound, and provides a range of results through 3D numerical simulations and stochastic weather forecast models to comprehensively analyze the uncertainty of numerical modeling and estimated results. Additionally, the study demonstrates the significant advantage of the joint approach in seismoacoustic analysis.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Keehoon Kim, Michael E. Pasyanos
Summary: The Large Surface Explosion Coupling Experiment (LSECE) conducted in Yucca Flat at the Nevada National Security Site in 2020 aimed to provide ground-truth data for seismoacoustic wave excitation by large chemical explosions near the ground surface. The joint seismoacoustic analysis demonstrated the capability to improve accuracy of explosion yield and depth estimation.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Geochemistry & Geophysics
Sean R. Ford, Michael E. Pasyanos, Andrea Chiang
Summary: This study uses the Pasyanos and Chiang (2022) dataset to calculate the seismic moment of explosions and validate the relationship between explosive yield and seismic moment. By correcting the seismic moment and testing multiple explanatory variables, a simple model for predicting explosive yield is obtained.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Geochemistry & Geophysics
Thabita Barbosa, Jordi Julia, Aderson F. Do Nascimento
Summary: The lithospheric structure of the on-shore Potiguar Basin was studied using joint inversion of receiver functions and surface-wave dispersion. Results showed a relatively thin crust of about 30 km below the basin and a thicker crust of about 32 km around it. Anomalous uppermost mantle with a velocity of 4.3 km/s was found at 30-40 km depth, and a negative velocity gradient at -125 km depth possibly represents a shallow Lithosphere Asthenosphere Boundary (LAB). The presence of magmatic intrusions below the Moho and heating from the active, hot sublithospheric mantle may explain the thin lithosphere and elevated heat flow observed at the surface.
JOURNAL OF GEODYNAMICS
(2023)
Article
Geochemistry & Geophysics
Cicero Costa da Silva, Esteban Poveda, Renato Ramos da Silva Dantas, Jordi Julia
Summary: Seismic ambient noise analysis has been shown to be an effective alternative to seismic wave analysis, providing information on Green's functions and enabling high-resolution tomographic studies in regions of low seismic activity.
PURE AND APPLIED GEOPHYSICS
(2021)