Journal of Structural Geology最新文献

{"title":"Fault detection based on U-Net and GNN integration","authors":"Guoqing Lu ,&nbsp;Lianbo Zeng ,&nbsp;Guoping Liu ,&nbsp;Jian Su ,&nbsp;José Luis Drummond Alves ,&nbsp;Junfeng Zhao ,&nbsp;Mehdi Ostadhassan","doi":"10.1016/j.jsg.2025.105426","DOIUrl":"10.1016/j.jsg.2025.105426","url":null,"abstract":"<div><div>Current fault detection methods mainly take advantage of a convolutional neural network, simplified U-Net, for seismic image semantic segmentation, which is a computer vision task aimed at generating a dense pixel-wise segmentation map of an image, where each pixel is assigned to a specific class or object. However, these methods face challenges such as unclear segmentation boundaries and limited receptive fields, which hinder the model's capability to detect all features of the fault. To address these issues, this paper proposes a method based on the integration of Graph Neural Network (GNN) and U-Net, referred to as GNU-Net, which incorporates fault graph structures and graph computation modules into U-Net. This approach aims to expand the receptive field, clarify segmentation boundaries, and optimize fault segmentation and continuity analysis through a joint loss function. The method consists of five modules: graph construction, data augmentation, fault segmentation, fault continuity analysis, and joint training. The graph construction module grids the fault labels with a grid edge length of 8 voxels, sets vertices at the locations where the fault intersects the grid, and selects representatives from the voxels labeled as faults within each grid as vertices. The dilation function is applied to expand the fault voxels in the labels and construct a velocity field, in which the geodesic distance between vertices is computed to establish connections between vertices. Data augmentation of the 3D seismic data and fault labels is achieved by rotating the images. A custom rotation matrix is applied to transform the vertex feature coordinates of the graph structure, significantly increasing the size and diversity of the training dataset. The fault segmentation module employs a simplified U-Net with square convolution kernels, and the segmentation loss includes both Dice and binary cross-entropy losses. The fault continuity analysis module leverages a graph neural network with irregular convolution kernels to capture macroscopic fault features and enhance fault continuity, employing a connection loss based on binary cross-entropy. Compared to the original U-Net, the modified GNU-Net achieves a fault detection accuracy of 97.39 % on the testing set, an improvement of 3.96 % over the original U-Net.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105426"},"PeriodicalIF":2.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Subduction of the Ontong Java Plateau: Insights from seismic reflection imaging of the forearc along the West Melanesian Trench","authors":"Qianqian Li ,&nbsp;Sanzhong Li ,&nbsp;Wei Gong ,&nbsp;Lei Xing ,&nbsp;Hongwei Liu ,&nbsp;Chong Xu ,&nbsp;Xiaodian Jiang","doi":"10.1016/j.jsg.2025.105425","DOIUrl":"10.1016/j.jsg.2025.105425","url":null,"abstract":"<div><div>The Ontong Java Plateau (OJP), as the largest oceanic plateau in the world, has drawn much attention because of its subduction along the West Melanesian Trench and the North Solomon Trench. Based on the first observed multichannel seismic (MCS) and multibeam data across the northwestern margin of the OJP, we show that the forearc region along the West Melanesian Trench is dominated by a series of normal faults which show this trench as an erosive subduction zone. Under the control of the seaward-tilting normal faults, the forearc region presents the topographic characteristics of gradually descending toward the trench and can be divided into the upper slope, middle slope and lower slope. However, some areas of the forearc region may be affected by underplating duplex deformation at the upper/lower plate interface, which leads to the formation of the outer-arc high and modification of the early tectono–stratigraphic structure, along with a series of arcward-tilting normal faults. We suggest that the forearc region between New Ireland Island and the West Melanesian Trench generally exhibits a strong extension, which is in sharp contrast to the thrust-imbricate collage of the forearc region east of the Solomon Islands. The extension indicates that the buoyant OJP is not subducted beneath the New Ireland Island along the West Melanesian Trench but may be collocated only with the overriding island arc system, as evidenced by no relative motion between the Pacific Plate and the New Ireland Island Arc and few earthquakes in the inactive trench.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"196 ","pages":"Article 105425"},"PeriodicalIF":2.6,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of kinematics of deformation on polycrystalline halite dynamic recrystallization: Full-field simulation of simple shear versus pure shear","authors":"Baoqin Hao ,&nbsp;Albert Griera ,&nbsp;Maria-Gema Llorens ,&nbsp;Paul D. Bons ,&nbsp;Ricardo A. Lebensohn ,&nbsp;Yuanchao Yu ,&nbsp;Enrique Gomez-Rivas","doi":"10.1016/j.jsg.2025.105424","DOIUrl":"10.1016/j.jsg.2025.105424","url":null,"abstract":"<div><div>Rock salt, composed mainly of halite, flows viscoplastically over a wide range of geological conditions, strongly impacting the dynamic evolution of sedimentary basins and orogens. Understanding how dislocation creep, which involves dislocation glide, intracrystalline recovery and dynamic recrystallization, influences the microstructure and rheology of halite under various deformation kinematics and temperatures is crucial for enhancing knowledge of salt flow dynamics. This study employs a full-field numerical simulation method to compare the viscoplastic deformation of polycrystalline halite under simple shear and pure shear conditions up to a natural strain of <em>ε</em> = 1.5 at temperatures ranging from 100 °C to 300 °C. The results are presented in terms of crystallographic preferred orientation (CPO), grain shape preferred orientation (SPO), subgrain boundary direction, grain size and strain rate distribution. The results indicate that the crystallographic anisotropy of individual halite crystals is transferred to the polycrystalline scale, resulting in strain localization, particularly in simple shear simulations. The kinematics of deformation affect the evolution and distribution of high strain-rate bands, determining the direction of intragranular substructures and the morphology of strain-induced grain boundaries, with minimal impact on grain size. The intensity of grain boundary migration increases with temperature, significantly influencing grain morphology and size, thereby obscuring strain localization, while having little effect on CPOs. At low strain (<em>ε</em> &lt; 1.0), CPOs relative to both the maximum shortening direction and the grain SPO are similar regardless of the deformation kinematics. At high strain (<em>ε</em> &gt; 1.0), simple shear CPOs exhibit three stronger {100} maxima with a monoclinic symmetry relative to the grain SPO compared to the six {100} maxima with an orthotropic symmetry relative to the grain SPO generated under pure shear. Therefore, microstructures and CPOs can serve as indicators of the strain path in polycrystalline halite under various conditions, aiding in determining the shear sense and elucidating the deformation kinematics of salt structures.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105424"},"PeriodicalIF":2.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water-fluxed melting and rheological weakening within the continental-scale Ailaoshan-Red River strike-slip shear zone, Western Yunnan, China","authors":"Lirong Tao ,&nbsp;Shuyun Cao ,&nbsp;Wenyuan Li ,&nbsp;Xuemei Cheng ,&nbsp;Jianhua Liu ,&nbsp;Yanlong Dong ,&nbsp;Haobo Wang ,&nbsp;Lefan zhan ,&nbsp;Dingkui Zhou ,&nbsp;Jianwei Fan ,&nbsp;Yun Tian","doi":"10.1016/j.jsg.2025.105416","DOIUrl":"10.1016/j.jsg.2025.105416","url":null,"abstract":"<div><div>While dehydration melting is universally acknowledged as a crucial factor in the evolution of the continental crust, the significance of water-influxed melting frequently receives insufficient attention. The Ailaoshan-Red River shear zone (ASRR-SZ) stands as one of the continental-scale exhumed strike-slip faults that have significantly contributed to the intraplate deformation and the collision between the Indian and Eurasian Plates. In a combined analysis of field-based structures, petrology, whole-rock geochemistry, zircon geochronology, phase equilibrium modeling, and Electron Backscatter Diffraction (EBSD) textures of leucogranites and migmatites within ASRR-SZ, the results reveal typical water-influxed melting characteristics. The leucogranites are characterized by high contents of Sr, Ba, and Ca, elevated ratios of Th/U and Zr/Hf, and low levels of Rb, Nb, Ta, as well as low Rb/Sr and Sr/Y ratios. Despite increasing Sr contents and decreasing Ba contents, the Rb/Sr ratios of leucogranites remain remarkably stable. The melting reactions identified are Qz + Pl + Kfs + H₂O = Melt and Pl + Ms + Qz + H₂O = Melt, with an additional 2.75 wt% of H₂O. Quartz grains from both leucogranites and migmatites display ductile deformation features indicative of grain boundary migration recrystallization, occurring at temperatures ranging from 424 °C to 678 °C. The timing of water-influxed melting within the shear zone was determined to be 32–26 Ma, which is consistent with left-lateral strike-slip shearing (31–20 Ma). The process of anatexis not only significantly affects the thermodynamic and rheological properties of rocks, but also the migration of melts can facilitate crustal differentiation, resulting in the formation of extensive leucogranites. The process plays a crucial role in the origin, modification, and stabilization of the continental crust.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105416"},"PeriodicalIF":2.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soft-sediment deformation structures in the Wangshi Group of the southern Tan-Lu Fault Zone, eastern China: implications for the Late Cretaceous tectonic activities and seismic events","authors":"Lianji Liang ,&nbsp;Junjie Zhang ,&nbsp;Hongshui Tian ,&nbsp;Hanchao Jiang ,&nbsp;Ning Zhong ,&nbsp;Ruixiang Fan","doi":"10.1016/j.jsg.2025.105422","DOIUrl":"10.1016/j.jsg.2025.105422","url":null,"abstract":"<div><div>A variety of soft-sediment deformation structures (SSDSs) were identified in the Late Cretaceous Wangshi Group, which is situated in the South Malingshan Hill in the southern segment of the Tan-Lu Fault Zone (TLFZ), eastern China. The SSDSs mainly formed in the piedmont-diluvial, alluvial, and lacustrine stratum in the Gaoshan-Tancheng graben basin bounded by the normal fault systems within the TLFZ. In this study, the morphological features and formation mechanisms of SSDSs have been investigated, and potential linkage between the formation of SSDSs and regional tectonic activities has been inferred. The results showed that the types of SSDSs observed in this area consist of the liquefied sand veins, liquefied sand dykes, liquefied breccias, diapirs, convolute laminations, soft boudinage structures, load and flame structures, ball-and-pillow structures, seismic folds, seismic slumps, syn-sedimentary faults, seismic fissure fillings and flowing structures of thixotropic soft clay. The analysis of SSDSs reveals that their deformation mechanisms can be attributed to the liquefaction, fluidization, thixotropy, plastic and brittle deformations within sandy, silty, and clay alternating stratigraphic systems, driven by gravitational instabilities due to reversed density gradients, uneven loading, slope-related gravitational forces, and shear and lateral stresses. Considering the characteristics of SSDSs and geological setting, seismic events and fault activities are proposed as the most plausible triggers for SSDSs, indicating that at least 19 seismic events of magnitude M ≥ 5 have occurred in the Late Cretaceous period. The study also provided significant insight into the declining trend in tectonic and seismic activities during the Late Cretaceous period in this region.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105422"},"PeriodicalIF":2.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal constraints on the Longriba fault motion, Eastern Tibetan plateau","authors":"Zhongbao Zhao ,&nbsp;Yong Zheng ,&nbsp;Joseph G. Meert ,&nbsp;Xuxuan Ma ,&nbsp;Jiawei Pan ,&nbsp;Haijian Lu ,&nbsp;Dongliang Liu ,&nbsp;Chunrui Li ,&nbsp;Haibing Li","doi":"10.1016/j.jsg.2025.105415","DOIUrl":"10.1016/j.jsg.2025.105415","url":null,"abstract":"<div><div>The spatial and temporal evolution of active fault structures within the eastern Tibetan Plateau (ETP) helps constrain the tectonic and topographic history of that region. In this study, we focus on the tectonic evolution of the Longriba fault (LRF), located ∼170 km west of the Longmenshan thrust belt (LTB) in the interior of the plateau. Increasing geological and geophysical evidence indicates that the LRF, a prominent dextral strike-slip fault with minor thrust components, serves as a significant tectonic and topographic boundary within the ETP. The basement rocks deformed by the LRF experienced rapid cooling between ∼156 and 136 Ma based on three pairs of muscovite/biotite ⁴⁰Ar/³⁹Ar ages, while four illite K-Ar ages (∼37.8–35.6 Ma) from fault gouges from the fault indicate mineral growth during fault reactivation. These results, combined with regional chronology, document several thermotectonic stages in the ETP since the closure of the Paleo-Tethys in the Late Triassic. An early Cretaceous cooling event was identified, reflecting boundary fault reactivation and crustal thickening, due to the Lhasa-Qiangtang collision to the south. The ∼38 Ma illite K-Ar ages are coeval with the India-Asia ‘hard’ collision, indicating fault propagation into the interior of the ETP. This study concludes that far field effects of plate convergence may strongly control fault movement, reactivation and propagation within the ETP, as well as triggered several pulses of cooling. Therefore, episodic mountain building may be due to continued fault-induced crustal thickening and uplift in the ETP.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"196 ","pages":"Article 105415"},"PeriodicalIF":2.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation between cumulative horizontal extension and strike-slip displacement in releasing bends: Discrete element analysis","authors":"Lunyan Wei ,&nbsp;Guiting Hou ,&nbsp;Shangxin Wu ,&nbsp;Jinkai Xia","doi":"10.1016/j.jsg.2025.105406","DOIUrl":"10.1016/j.jsg.2025.105406","url":null,"abstract":"<div><div>Releasing bends are structural features formed by localized extension along strike-slip fault systems. Synclines, pull-apart basins, and extensional strike-slip duplexes develop mainly at releasing bends. Exploring the correlation between strike-slip displacement and cumulative horizontal extension displacement of transtensional structures could be useful for estimating strike-slip displacement when horizontal extension displacement (horizontal fault offsets of en echelon normal faults) is known. The formation and evolution of the releasing bend can be effectively simulated by 2D particle discrete element method. The microscopic parameters of the particles, such as effective modulus and stiffness ratio, are calibrated to model Young's modulus and Poisson's ratio. Six setups of simple strike-slip geometry and releasing bend geometries with different fault separations (the distances between adjacent faults) are then designed. The modelling results reveal a quantitative correlation between the strike-slip displacement L, the cumulative horizontal extension displacement <span><math><mrow><munderover><mo>∑</mo><mn>1</mn><mi>n</mi></munderover><mfrac><msub><mi>T</mi><mi>i</mi></msub><mrow><mi>sin</mi><mspace></mspace><msub><mi>θ</mi><mi>i</mi></msub></mrow></mfrac></mrow></math></span>, and the fracture propagation angle θ: <span><math><mrow><munderover><mo>∑</mo><mn>1</mn><mi>n</mi></munderover><mfrac><msub><mi>T</mi><mi>i</mi></msub><mrow><mi>sin</mi><mspace></mspace><msub><mi>θ</mi><mi>i</mi></msub></mrow></mfrac><mo>=</mo><mi>k</mi><mo>∗</mo><mi>L</mi></mrow></math></span>. The k value serves as a comprehensive coefficient to take complex factors into account. In our models, the k values range from 0.9 to 1.6 and are greater for soft rocks than for hard rocks. This quantitative correlation shows a good fit with several natural examples in similar strike-slip or pull-apart tectonic settings, effectively supporting our conclusion.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"196 ","pages":"Article 105406"},"PeriodicalIF":2.6,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distributions of throws, widths and scarp slopes on normal faults and their relations to fault growth: Insights from Auto_Throw code","authors":"Giampietro T ,&nbsp;Manighetti I ,&nbsp;Leclerc F ,&nbsp;Gaudemer Y","doi":"10.1016/j.jsg.2025.105393","DOIUrl":"10.1016/j.jsg.2025.105393","url":null,"abstract":"<div><div>Cumulative displacements on faults can tell us how they have accumulated over time, and thus how faults have grown. We approach this question from two angles, focusing on normal faults with topographic escarpment. First, we develop a code, Auto_Throw, to automate the measurements of throws on normal fault scarps. Using a piecewise linear fitting approach and basic slope and length constraints, Auto_Throw mathematically explores all possible configurations of scarps and offset surfaces on a topographic profile, so that a throw and its uncertainty are defined from the statistical analysis of tens to hundreds of measurements. Auto_Throw also measures the scarp slopes and the across-fault widths. We test Auto_Throw performance on 35 normal faults of different lengths and contexts, performing a million measurements. Second, we address the tectonic implications of the measurements. We conduct a global analysis of all fault data in order to smooth out site-dependent complexities and identify common features that may result from the fault growth process. We find that throws, scarp slopes and fault widths significantly vary along faults, yet in a similar manner for each fault quantity. Throw distributions show a common envelope shape, asymmetric with a long slip taper. Steepest scarp slopes are sub-constant along faults but systematically drop down towards fault tips. Fault width scales with throw, but a rough zone of constant width is identified off the faults. Tapering slip on a fault, shallowing of its scarp slope, and distributed deformation off its trace, could all be indicative of the fault lateral propagation.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"196 ","pages":"Article 105393"},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controls on shear band orientation in deforming porous rocks: Insights from improved microcrack segmentation method","authors":"Claudia Elijas-Parra ,&nbsp;Alexis Cartwright-Taylor ,&nbsp;Ian G. Main ,&nbsp;Rebeca E. Ursu ,&nbsp;Ian B. Butler ,&nbsp;Florian Fusseis","doi":"10.1016/j.jsg.2025.105404","DOIUrl":"10.1016/j.jsg.2025.105404","url":null,"abstract":"<div><div>High resolution, time-resolved X-ray imaging of deformation processes has revealed unprecedented detail on the microstructural and mechanical processes involved in system-scale failure during laboratory experiments. This has highlighted the role of the evolving crack population in controlling localisation. However, in porous rocks, accurate segmentation of evolving crack populations from the rock matrix and pre-existing pores is challenging because of the narrow aperture of cracks. Here we develop and test a new global statistical method of distinguishing between these three phases in tomographic slices, obtained from an X-ray transparent triaxial compression experiment on Clashach sandstone at 20 MPa effective pressure. Compared with a watershed-based method, the new method is less sensitive to artefacts of sampling at the voxel scale (<em>l</em> ≥ 40 μm). Furthermore, the segmented crack length distributions have a greater dynamic range, yielding exponents (1 ≤ <em>a</em>≤3) above 150 μm that are in the same range as those observed in field outcrop, while anisotropy in the crack orientation distribution is better represented. Using this new method, we observe the spontaneous localisation of cracks into a shear band, whose orientations evolve from a random distribution to one more favourably oriented for synthetic shear and tensile fracturing. The observed shear band orientation (∼60° dip) is intermediate between a directed percolation model (50°) and the mode of the crack orientation distribution in the shear band (66°).</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"196 ","pages":"Article 105404"},"PeriodicalIF":2.6,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strain partitioning and fault interaction during the 2023 Mw 6.8 Al-Haouz earthquake, Western High Atlas, Morocco","authors":"F. Carboni ,&nbsp;M. Occhipinti ,&nbsp;R. Lanari ,&nbsp;F. Medina ,&nbsp;T.-E. Cherkaoui ,&nbsp;R. Gaspari ,&nbsp;C. Faccenna ,&nbsp;C. Chiarabba ,&nbsp;M. Porreca","doi":"10.1016/j.jsg.2025.105394","DOIUrl":"10.1016/j.jsg.2025.105394","url":null,"abstract":"<div><div>This study employs a multidisciplinary approach to identify the seismogenic fault responsible for the Mw 6.8 Al Haouz earthquake of September 8, 2023, in the Western High Atlas, Morocco. In addition, considering the oblique slip dynamics and strain partitioning characteristic of the region, the study investigates potential interactions between fault systems at depth. Our new relocation of the mainshock confirms the depth of the mainshock at ca. 28 km, while our relocated aftershocks reveal clusters concentrated near the Tizi n’Test fault (TnTf) and aligned patterns consistent with fault-controlled seismicity. Focal mechanisms of the mainshock indicate a compressive event involving two nodal planes: a high-angle NW-dipping plane and a low-angle SW-dipping plane. DInSAR analysis generated displacement maps for vertical and horizontal (E-W) components, revealing an asymmetric SW-verging uplift bounded, in the south, by the NW-dipping Tizi n’Test fault (TnTf). The Triangular Elastic Dislocation (TDE) method is conducted to simulate complex faults geometries using geological data and focal mechanism solution.</div><div>The NW-dipping TnTf shows a better fit with the observed deformation compared to the SW-dipping Jebilet Thrust (JTt), which contributed with a minor role. Coulomb stress changes calculated from the TDE model correlates with aftershocks distribution, further supporting the TnTf as the causative fault, with a partial influence of the JTt.</div><div>Our findings emphasize the value of integrating geodetic observations with advanced modelling to enhance the understanding of the seismotectonic framework, offering a refined reconstruction of the Western High Atlas's deformation processes during the 2023 Al Haouz earthquake.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"195 ","pages":"Article 105394"},"PeriodicalIF":2.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143594207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}