Journal of Structural Geology最新文献

{"title":"FAULT-CONTROLLED GYPSUM VEIN NETWORKS: INSIGHTS FROM THE ACTIVE GALERA FAULT, SOUTHERN SPAIN","authors":"Medina-Cascales I. ,&nbsp;Carrazana A. ,&nbsp;Gomez-Rivas E. ,&nbsp;Martin-Rojas I. ,&nbsp;García-Tortosa F.J. ,&nbsp;Bons P.D. ,&nbsp;Alfaro P.","doi":"10.1016/j.jsg.2025.105423","DOIUrl":"10.1016/j.jsg.2025.105423","url":null,"abstract":"<div><div>Veins provide insights into the strain conditions under which they formed, the timing and sequence of fracturing, and the nature of the fluids from which their cement precipitated. Intense fracturing within fault zones promotes vein formation, but there are still open questions about the extent of fault control on vein formation, the type of veins and their development. This study analyses the influence of an active strike-slip fault —the Galera Fault, Southern Spain— on the formation, distribution, and evolution of gypsum vein networks hosted in Pliocene and Pleistocene rocks. Field mapping and structural analysis reveal veins are concentrated within the fault damage zone, with their spatial distribution being controlled by fault geometry, kinematics, and the lateral continuity of host lithologies. Structural analysis at 18 sites indicates that vein orientation correlates with tectonic structures. Veins near faults exhibit organized, consistent strikes, while those farther away show more variable orientations. Vein strike is highly sensitive to the local strain defined by the geometry, kinematics, and interactions of faults and subsidiary structures. Additionally, vein length tends to increase near faults. Vein intensity and density are controlled by vein length and orientation, and the thickness of vein-hosting beds. Moreover, veins formed shortly after sediment deposition under minimal lithostatic load, likely driven by fault-related strain. This early formation is supported by microstructures such as cone-in-cone and the rotation of early veins due to tectonic tilting. In conclusion, this research highlights the strong tectonic influence on vein formation, evolution, distribution, and attributes.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105423"},"PeriodicalIF":2.6,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792773","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":"Using 3D models to test geological hypotheses for sill complex geometries: Application to Jurassic dolerite intrusions, Tasmania","authors":"Fernanda Alvarado-Neves,&nbsp;Laurent Ailleres,&nbsp;Lachlan Grose,&nbsp;Alexander R. Cruden,&nbsp;Robin Armit","doi":"10.1016/j.jsg.2025.105420","DOIUrl":"10.1016/j.jsg.2025.105420","url":null,"abstract":"<div><div>This study employs three-dimensional (3D) geological modelling to test competing hypotheses regarding the subsurface architecture of Jurassic dolerite sills in the Hobart region, Tasmania. Although this sill complex has been extensively studied, there is little subsurface data, making it an excellent case study for using 3D models to better understand its architecture. Four alternative models are built using the <em>LoopStructural</em> Python library, which incorporates rules from intrusion emplacement mechanisms into the modelling workflow. All four models are constrained using the same input dataset, comprising field measurements, most of which are located in the southwest part of the study area. The differences between the models are governed primarily by which pre-intrusion mechanical anisotropy facilitated emplacement of the dolerite. The models are visually and quantitatively compared with the published geological map of the area and with field observations. The results of this comparison suggest that northeast and northwest-trending outcrop patterns of the dolerite are likely related to the presence of transgressive sheets within sedimentary host rocks of the Permo-Triassic Parmeener Supergroup, and that the occurrence of dolerite sills at different stratigraphic and structural levels is likely due to a combination of primary intrusive steps and post-intrusion faults.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105420"},"PeriodicalIF":2.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792774","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":"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":"Reactivation potential of inherited structures on southwestern Grand Banks, Newfoundland, Canada","authors":"Ai Gusti Guna ,&nbsp;Jeremy Rimando ,&nbsp;Alexander L. Peace ,&nbsp;Katsuichiro Goda ,&nbsp;Justiina T.S. Devries","doi":"10.1016/j.jsg.2025.105414","DOIUrl":"10.1016/j.jsg.2025.105414","url":null,"abstract":"<div><div>The November 18, 1929, M 7.2 Grand Banks earthquake occurred in the Laurentian Channel near the crest of the continental slope off the eastern coast of Canada. This seismic event, followed by a tsunamigenic landslide, is the largest instrumentally recorded earthquake that has occurred in the region. The event led to 28 confirmed casualties and significant destruction of critical commercial infrastructure and operations, including trans-Atlantic telecommunications cables and coastal facilities serving communities in southern Newfoundland. Despite the significance of this event, there is a limited understanding of the structural setting and neotectonics of the region. Imaging deep structures where the earthquake likely occurred is challenging, but shallow rift-related structures, influenced by deeper faults through structural inheritance, offer valuable insights into this deeper system. Here, we apply this concept through the analysis and interpretation of key regional faults on two-dimensional offshore seismic reflection data. Then, using slip tendency analysis, the reactivation potential of these structures under the present-day stress field was calculated. The analysis shows that regional NW-SE-striking normal faults, dipping at 40°– 60°, have high slip tendency values, offering insights into potentially active fault locations and geometries that support seismic hazard assessment and earthquake scenario modeling to assess impacts on populations and assets in southern Newfoundland.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105414"},"PeriodicalIF":2.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918217","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":"Crustal deformation studies in Jammu Himalaya using PSInSAR technique","authors":"Ajay Kumar Taloor ,&nbsp;Girish Ch Kothyari","doi":"10.1016/j.jsg.2025.105405","DOIUrl":"10.1016/j.jsg.2025.105405","url":null,"abstract":"<div><div>The Jammu Himalaya lies within the deformation zone affected by the 1905 Kangra and 2005 Kashmir earthquakes, where continuous micro-seismic activity has been observed. To understand the patterns of active crustal deformation, Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) and stream power law equations have been applied to analyse the brittle crust of the Tawi Basin in the northwestern Himalaya. The PSInSAR-based results reveal that from 2017 to 2020, the region experienced active surface deformation with a mean velocity of +16 to −18 mm/yr and a standard deviation of 0–5 mm/yr. These rates align with previous Global Positioning System (GPS) base geodetic arc normal observations (11.2 ± 3.8 mm/yr to 14 ± 2 mm/yr) in the northwest Himalaya. The PSInSAR data show Line of Sight (LoS) displacements ranging from +45 mm to −50 mm, with negative values indicating tectonic subsidence, mass wasting, and erosion, while positive values suggest uplift and sediment deposition. The LoS displacement varied between −50 mm and +40 mm to the south and north of the Mandili-Kishanpur Thrust (MKT), respectively, and these values are consistent with the observed Gradient Length Anomalies (GLA). Crustal deformation is notably high in the hilly and mountainous regions, with knickpoint analysis indicating that uplift associated with crustal shortening contributes to the development of knickpoints. Further, the Tawi river basin in the northwestern Himalayan region is prone to landslides, with high steep slopes in the northern part of the Main Central Thrust (MCT) and Main Boundary Thrust (MBT) zones, being particularly vulnerable, and footwall subsidence to the south potentially linked to active thrust faulting.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"197 ","pages":"Article 105405"},"PeriodicalIF":2.6,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843328","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}