Article
Geochemistry & Geophysics
Xueyang Bao, Lianghui Guo, Yang Shen
Summary: Detailed three-dimensional models of crustal compositional variations are essential for better understanding crustal evolution and dynamics. The study presents a new method for obtaining a geophysical model of Southern California, revealing detailed features of compositional variations in the crust of the region.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Nanqiao Du, Zhiwei Li, Tianyao Hao, Xin Xia, Yutao Shi, Ya Xu
Summary: A joint tomographic inversion method combining seismic surface wave dispersion and gravity data was developed in this study to achieve more reliable crustal 3-D shear wave structures. The method was shown to better match the gravity data and provide more constraints into the model resolution, improving the reliability of the results.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
G. Maurizio, C. Braitenberg, D. Sampietro, M. Capponi
Summary: In this study, a new model for the crust and upper mantle in Iran is proposed by jointly inverting gravity and magnetic fields, constrained with a seismic tomography model. The study finds that the crustal density and rigidity variations have a significant impact on the seismic activity and active faulting in the region, and are consistent with the geological features. The study also reveals the correlation between the Neo-Tethys and Paleo-Tethys sutures and crustal density variations. Finally, a reliable model of the lithosphere in the Iranian collision belt is built through a 3D Bayesian joint inversion.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Geochemistry & Geophysics
Jie Liu, Jianzhong Zhang
Summary: This paper introduces a structure-based joint inversion method that uses seismic reflection traveltimes, slopes, and Bouguer gravity anomaly data to simultaneously build velocity and density models. The method improves the distribution and structural features of physical properties, especially in deep and complex tectonic situations.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Engineering, Geological
Beatriz Benjumea, Anna Gabas, Albert Macau, Juanjo Ledo, Fabian Bellmunt, Sara Figueras, Jordi Pina
Summary: Identification of undercover karst areas is essential for engineering or hydrogeological studies. This study conducted in the Montgri Massif in Costa Brava, Spain, used geophysical techniques to delineate and characterize karst structures, with the Fuzzy c-means approach providing integrated geological models.
ENGINEERING GEOLOGY
(2021)
Article
Geochemistry & Geophysics
Chen Liao, Xiangyun Hu, Shihui Zhang, Xuewen Li, Quanzeng Yin, Zhao Zhang, Longfei Zhang
Summary: Joint inversion is an effective technique for obtaining high-resolution solutions in geophysics. In this study, a new inversion strategy based on the alternating direction method of multipliers was proposed for convenient and efficient joint inversion. Three optimization algorithms were presented for different types of geophysical data, resulting in more accurate results compared to separate inversions. The algorithms were successfully applied to field data, verifying the practicality of the inversion strategy.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Rongzhe Zhang, Tonglin Li, Cai Liu, Haoyuan He, Xingguo Huang, Saeed Vatankah
Summary: Joint inversion algorithms have received much attention in geophysical interpretation due to their ability to reduce the uncertainty of inverse solutions. However, a single coupling constraint may not provide the optimum solution for all geological scenarios. In this study, a new joint inversion algorithm based on a mixed structural and rock-physics coupling constraints is proposed. The algorithm incorporates a structural coupling constraint and a rock-physics coupling constraint to improve the application of multiple geophysical data sets. The results show a significant improvement in the resolution of the reconstructed models compared to traditional single coupling algorithms.
Article
Geochemistry & Geophysics
Yuqi Huang, Max Moorkamp, Ji Gao, Haijiang Zhang
Summary: On 3 August 2014, a destructive earthquake occurred in Ludian, Yunan, China, resulting in significant casualties. To understand the seismogenic structure of this earthquake, the study developed a three-dimensional joint inversion algorithm combining magnetotelluric data and seismic body wave arrival times. The models generated from this algorithm revealed low Vp/Vs ratios and resistivity in the upper crust of the main shock zone, as well as the presence of cracks/fractures, fluids, and high quartz contents. These findings suggest that fluids and high quartz contents may have played a role in promoting the Ludian earthquake. This study provides new evidence on how crustal properties influence the genesis of moderate to large earthquakes.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Multidisciplinary Sciences
Yunfeng Chen, Erdinc Saygin, Brian Kennett, Mehdi Tork Qashqai, Juerg Hauser, David Lumley, Mike Sandiford
Summary: This study constructs a new high-resolution 3D shear velocity model of the Australian continent using an extensive seismic dataset and a new imaging workflow. The model reveals detailed crustal structures that shed light on undercover mineral exploration.
NATURE COMMUNICATIONS
(2023)
Article
Geochemistry & Geophysics
Bo Yang, Kaijun Xu, Zhan Liu
Summary: Magnetotelluric (MT) inversion algorithms play a crucial role in exploration geophysics, yet face the challenge of non-uniqueness in inverse problems. Machine learning techniques have been utilized to address the ambiguity in geological interpretations caused by the smoothness of resistivity models in MT inversions. The study introduces an effective MT inversion method based on FCM clustering algorithm, integrating geophysical inversion and geological differentiation.
SURVEYS IN GEOPHYSICS
(2021)
Article
Geochemistry & Geophysics
Qingfa Meng, Guoqing Ma, Lili Li, Taihan Wang, Zongrui Li, Nan Wang, Jingyu Li
Summary: The joint inversion of gravity and magnetic data using tetrahedral unstructured grid and volume weighting function is developed to map the ore distribution. The method is applied to mineral exploration data from the Huanggangliang-Ganzhuermiao metallogenic belt, and the prediction of favorable mineralization areas is achieved. The analysis of deep inversion results reveals the similarity of two mineral deposits and the difference in their migration structural environments.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Mathematics, Applied
Emad Ghalenoei, Jan Dettmer, Mohammed Y. Ali, Jeong Woo Kim
Summary: Typical geophysical inverse problems are challenging due to their ill-posed nature and non-uniqueness. Deterministic inversion methods often apply constraints to parameter values, but this may limit inference on complex structural boundaries. Bayesian trans-dimensional approaches offer adaptive parametrizations and can avoid over-parametrization or under-parametrization. However, they depend on the choice of partitioning types and involve trade-offs between spatial resolution and correlated data errors. The presented hierarchical model incorporates trans-D parameterizations for both spatial and data noise, providing a more comprehensive uncertainty quantification that considers the trade-offs between noise and structure.
Article
Multidisciplinary Sciences
Xinpeng Pan, Dazhou Zhang, Pengfei Zhang
Summary: This study proposes a more robust azimuth-dependent seismic inversion method by combining Bayesian inference and joint time-frequency-domain inversion theory, introducing regularizations to improve inversion reliability. The comparison of frequency bandwidth under different noise levels demonstrates that joint time-frequency-domain inversion may provide a more stable technique for fracture detection in fractured reservoirs.
SCIENTIFIC REPORTS
(2021)
Article
Geochemistry & Geophysics
Chao Zhang, Qingxiang Meng, Cheng Li
Summary: This article introduces a curvelet-based joint waveform and envelope inversion (CJWEI) method for imaging near-surface structures. By inverting two types of data, this method efficiently recovers low- and high-wavenumber structures and mitigates the cycle-skipping problem. Synthetic tests and real data applications demonstrate the effectiveness and robustness of this method in constraining anomalies and hidden layers in shallow structures.
Article
Geochemistry & Geophysics
Runxin Niu, Guoqing Ma, Taihan Wang, Lili Li, Tong Gao
Summary: This paper proposes an unstructured grid method for joint inversion of gravity and magnetic anomalies, and introduces an adaptive subdivision method based on anomaly feature to improve computation efficiency. Synthetic tests on a dipping-slab model show that the proposed method can complete the joint inversion and effectively recover the distribution characteristics of the field source. Finally, the method is applied to real gravity and magnetic data to determine the range of favorably mineralized regions in Shandong, China, providing an important basis for further exploration.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)