Tectonophysics最新文献

{"title":"3D azimuthal anisotropy model reveals crust-mantle deformation in the northeastern Songpan-Ganzi Block and adjacent regions","authors":"Yue Chen ,&nbsp;Qianzong Bao ,&nbsp;Xiaofei Chen","doi":"10.1016/j.tecto.2025.231043","DOIUrl":"10.1016/j.tecto.2025.231043","url":null,"abstract":"<div><div>The northeastern Songpan-Ganzi Block (NE-SPGZ), as the leading edge of the Tibetan Plateau's eastward expansion, remains controversial in its crust-mantle deformation mechanisms. Using teleseismic and ambient noise surface wave dispersion data, we obtained the 3D shear wave velocity and azimuthal anisotropy structure from 5 to 110 km depths. The results show low-velocity anomalies in the upper mantle of the NE-SPGZ and the western Qinling Orogenic Belt (WQL), which may be related to the thermal erosion and localized upwelling of asthenosphere. In the NE-SPGZ, the crust exhibits dominant NW-oriented fast-axis direction consistent with the regional tectonic trend, indicating overall crustal shortening. However, the upper mantle shows NE-oriented fast-axis direction with increased amplitude of anisotropy. We suggest that the combined effect of the asthenospheric activity, northeastward plateau compression, and Sichuan Basin resistance may result in significant NE-directed deformation within the softened upper mantle. The lower crustal low-velocity zone in the NE-SPGZ, generated by felsic crustal deformation, exhibits lateral heterogeneity in its anisotropy. Therefore, we infer that this zone may buffer crust-mantle decoupling. In the WQL, the fast-axis direction is consistently and strongly NW-oriented from crust to upper mantle, revealing the vertically coherent deformation in its weakened lithosphere. Conversely, the central Qinling Orogenic Belt and northern Yangtze Block are characterized by high-velocity lithospheres with weak anisotropy, indicating stable tectonic features and being less directly affected by the plateau expansion. The differential responses of these lithospheric blocks to the eastward plateau expansion reflect complex deep dynamic processes in the region.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"922 ","pages":"Article 231043"},"PeriodicalIF":2.6,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145785282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stratigraphic and provenance analysis of the Alamor–Lancones Basin: Implications for the Cretaceous–Paleocene tectono–magmatic evolution of the northern Andean forearc system","authors":"Hugo Carrasco ,&nbsp;Cristian Vallejo ,&nbsp;Cristian Nuñez ,&nbsp;José Herrera ,&nbsp;Lily J. Jackson ,&nbsp;Brian K. Horton ,&nbsp;Tonny Thomsen ,&nbsp;Pieter Vermeesch ,&nbsp;Wilfried Winkler","doi":"10.1016/j.tecto.2025.231037","DOIUrl":"10.1016/j.tecto.2025.231037","url":null,"abstract":"<div><div>The Cretaceous–Paleocene Alamor–Lancones Basin is a well-preserved and long-lived forearc basin in southwestern Ecuador and northwestern Peru. It occupies a key morphotectonic region of the northern Andes, where the forearc transitions from continental basement in the south to accreted oceanic terranes in the north. This study investigates the stratigraphic evolution of the basin through provenance analysis of siliciclastic units and their response to fluctuating tectonic regimes that influenced the region. The oldest basin fill corresponds to the fluvial–alluvial Sábalos Formation, which unconformably overlies marine Paleozoic metasedimentary rocks of the El Tigre Unit. Whereas the lower Sábalos Formation was derived from exhuming crustal rocks, the upper levels record increasing input from coeval Aptian–early Albian volcanism. A shift to an extensional tectonic regime led to mid-Cretaceous lithospheric thinning, normal faulting, and submarine mafic volcanism of the continental Celica–Lancones Arc (∼105–91 Ma). Extension-related subsidence resulted in a transition to marine sedimentation, as recorded by the Puyango and Ciano formations during the middle Albian–Turonian. Following a Santonian compressional event (∼85 Ma), deep-marine deposition of the Zapotillo Group in the basin documents pre-, syn-, and post-accretion of the Caribbean Large Igneous Province (CLIP). Pre-accretional forearc sedimentation, as represented by the Santonian–late Campanian Chaquino and Tronco Quemado formations, records magmatic arc provenance with minor continental basement input. A latest Campanian–Maastrichtian shift to dominantly crustal provenance within the Mangahurco and Cañaveral formations provides evidence for exhumation of forearc basement rocks north of the basin in response to accretion of the CLIP at ∼75–70 Ma. Post-accretional accumulation of the Cazaderos and Casanga formations (∼66 Ma) recycled late Maastrichtian–Paleocene magmatic arc detritus from the emerging continental Sacapalca Arc. Overall, the evolution of the Alamor–Lancones Basin highlights how temporal shifts in the regional tectonic regime exerted first-order control on forearc deformation (basin subsidence and inversion), sediment provenance, and coeval arc magmatism, the latter also recorded by detrital zircon Th/U ratios.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"921 ","pages":"Article 231037"},"PeriodicalIF":2.6,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145753516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Segmented crustal magma reservoirs beneath the Kula Volcanic Province (Western Anatolia) revealed by 3D MT imaging","authors":"Özgür Karaoğlu ,&nbsp;Mehmet Emin Candansayar ,&nbsp;Özcan Özyıldırım ,&nbsp;Ahmet Yıldız ,&nbsp;Can Başaran ,&nbsp;İsmail Demirci ,&nbsp;Yıldırım Dilek","doi":"10.1016/j.tecto.2025.231040","DOIUrl":"10.1016/j.tecto.2025.231040","url":null,"abstract":"<div><div>The Kula Volcanic Province (KVP) in western Anatolia represents the youngest expression of intraplate volcanism within the Aegean extensional province. Yet, the geometry and depth of its magma storage system have remained poorly constrained. Here we present the first three-dimensional magnetotelluric (MT) inversion of the region, based on a dense dataset of 105 stations across ∼60 × 60 km². The results reveal a major mid-crustal reservoir, ∼75 × 20 km in extent and emplaced between 5 and 25 km depth, accompanied by several smaller chambers up to 12 km across. Diapir-like protrusions extend from these bodies to depths of ∼5 km, their NNW–SSE orientation closely aligned with the fault architecture of the Gediz Graben.</div><div>Resistivity values below 5 Ω.m correspond to melt fractions exceeding 6–8 %, providing robust geophysical evidence for significant partial melts in the mid-crust. Petrological constraints indicate primary melts originated from the asthenospheric mantle at 65–90 km depth, while the anomalies resolved here represent secondary crustal reservoirs where ascending basaltic magmas became trapped and stabilised. This dual structure—deep mantle melting coupled with mid-crustal storage—reconciles geochemical constraints with geophysical imaging and highlights the segmented nature of the system, in which one dominant reservoir is compartmentalised by regional fault networks into smaller magma bodies.</div><div>These findings provide the first direct evidence for fault-controlled magma storage beneath the KVP. The identification of shallow intrusions reaching ∼5 km depth explains the localisation of Holocene volcanism, including the ∼4.7 ka Çakallar eruption, and points to a latent volcanic hazard. Placed in a global context, the KVP demonstrates how asthenospheric upwelling, lithospheric thinning, and tectonic segmentation combine to generate compartmentalised magma systems in highly extended continental crust.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231040"},"PeriodicalIF":2.6,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145753514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complex nature of the crustal anisotropy in the western margin of the Indian subcontinent and its geodynamic implications","authors":"Sowrav Saikia ,&nbsp;Rakesh Prajapat ,&nbsp;Sumer Chopra ,&nbsp;Santosh Kumar ,&nbsp;Vinay Kumar Dwivedi ,&nbsp;Vikas Kumar","doi":"10.1016/j.tecto.2025.231039","DOIUrl":"10.1016/j.tecto.2025.231039","url":null,"abstract":"<div><div>The intraplate Gujarat region has thick crust which is undergoing deformation. Although the deformation process in the region is evident in the surface geological process, understanding the deeper geodynamic mechanism requires geophysical investigations. The crustal anisotropy can throw light on the nature of deformation of the crust and its geodynamic implications on overall tectonics of the region. This present study analyze the spatio-temporal variations of crustal anisotropy using teleseismic earthquakes recorded at 56 permanent stations and 20 temporary stations of the Gujarat State seismic network. The primary findings of 1306 pairs of radial and tangential components Pms phase splitting shows spatial variations in fast directions, aligned with major tectonic features and rest of some are aligned with absolute plate motion of Indian plate. The strength of the anisotropy is found to be low to average (average δt ∼ 0.10–0.45 s), suggesting the low deformations of the crust. The measurements of crustal anisotropy parameters indicate that anisotropy is attributed to the localized active faults, rather than affected by lower crust materials or horizontal compressive stress orientation. From the aligned/parallel trends of fast polarization direction (FPDs) of crustal anisotropy with the strike of active faults, the structure induced anisotropy is the primary cause of crustal anisotropy in Gujarat intraplate region.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231039"},"PeriodicalIF":2.6,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From fabric to process: An integrated study of deformed quartz-rich carbonates","authors":"Maria Eleni Taxopoulou ,&nbsp;Marine Lartigau ,&nbsp;Charles Aubourg ,&nbsp;Nicolas E. Beaudoin ,&nbsp;Elli-Maria Charalampidou ,&nbsp;Jean Paul Callot","doi":"10.1016/j.tecto.2025.231034","DOIUrl":"10.1016/j.tecto.2025.231034","url":null,"abstract":"<div><div>This study investigates the presence and nature of diffuse deformation in a low-porosity carbonate rock that underwent polyphase tectonics and contains a network of veins, tectonic stylolites, and deformation bands. By using a non-destructive methodology based on Electron Backscatter Diffraction, X-ray computed tomography, coupled with results from Anisotropy of Magnetic Susceptibility and the Fry technique, we examine the grain fabric and strain distribution within the rock. Our investigation reveals evidence of quartz reorientation with respect to the polyphase contractional history of the area. Several mechanisms of quartz reorientation were proposed, including rigid reorientation during rotation and diffusion-related processes. The coexistence of ductile and brittle deformation mechanisms in the carbonate matrix indicates a complex response to compaction which can be recorded by the matrix, but does not appear to have a direct effect on the actual amount of shortening, as this is predominantly affected by the deformation bands. Our findings highlight the complexity of strain accommodation, with diffuse deformation creating subtle variations in grain size, shape, and orientation within the carbonate matrix. The study enhances our understanding of deformation processes in poly-deformed carbonate rocks and provides valuable insights into the geological context of the studied locations, by using a novel technique that can be useful for gaining qualitative and quantitative information from the rock samples. However, linking specific reorientation mechanisms to individual tectonic events remains challenging due to the multifaceted nature of deformation processes operating over different magnitudes and timescales.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"923 ","pages":"Article 231034"},"PeriodicalIF":2.6,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanism and Co-seismic effects of the 2023 herat earthquake sequence in Afghanistan based on InSAR","authors":"Yuchao Zhong ,&nbsp;Hua Gao ,&nbsp;Hui Lin ,&nbsp;Guangcai Feng","doi":"10.1016/j.tecto.2025.231038","DOIUrl":"10.1016/j.tecto.2025.231038","url":null,"abstract":"<div><div>The October 2023 Herat earthquake sequence in western Afghanistan, involving four Mw 6.3 events, ranks among the most catastrophic seismic crises in the region over the past two decades, resulting in over 2000 fatalities and widespread structural collapse. This study integrates radar remote sensing technologies to investigate the focal mechanism and co-seismic impacts of this sequence. Firstly, co-seismic deformation was extracted from Sentinel-1 SAR images using Differential Interferometric Synthetic Aperture Radar (DInSAR) method. Then the Okada model was employed to invert fault geometry parameters and slip distribution. Furthermore, multi-temporal InSAR coherence analysis was performed to assess building damage, with a focus in critical zones such as Herat City and proximal villages. For the first two Mw 6.3 events, the ascending and descending deformation data reveal maximum of 33 cm and 54 cm in LOS direction, respectively. For the latter two Mw 6.3 events, the maximum are 58 cm and 76 cm. Through slip inversion, two distinct asperities were identified for the first two Mw 6.3 events (at depths of 5 km and 6 km) and another two for the latter two Mw 6.3 events (at depths of 6 km and 7 km, respectively). Fault model suggests that a concealed north-dipping fault between the Hari Rud and Siakhubulak fault zones imposes significant Coulomb stress perturbations on adjacent fault systems. Coherence analysis mapped severe damage in 12 villages near the epicenter, while collapsed structures in Herat City showed characteristic coherence difference values of 0.2–0.4. This study delivers co-seismic data for the Herat earthquake sequence, highlighting the seismic hazard in the future, quantified coherence difference provides a rapid proxy method for post-disaster building damage assessment, contribute to reconstruction in northwestern Afghanistan.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231038"},"PeriodicalIF":2.6,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics and generation mechanisms of tremors across a mountain belt","authors":"Yi-Chu Hua ,&nbsp;Kate Huihsuan Chen ,&nbsp;Satoshi Ide ,&nbsp;Pei-Ying Patty Lin","doi":"10.1016/j.tecto.2025.231036","DOIUrl":"10.1016/j.tecto.2025.231036","url":null,"abstract":"<div><div>We analyze ∼7000 tectonic tremors recorded between 2012 and 2022 across five clusters along Taiwan's mountain belt at depths of 30–50 km, providing new insights into slow fault slip within an active continental collision zone. All clusters occur above the Moho, exhibit thrust-dominant focal mechanisms, and are distinct from crustal seismicity. Tidal sensitivity varies spatially, with Clusters 2–5, located in zones of active collision and subduction termination, showing strong modulation (α = 0.53–0.75), while Cluster 1, situated in a post-collisional extensional environment near the Okinawa Trough, exhibits weaker sensitivity (α ≈ 0.3). These variations correlate with differences in tidal stress amplitude and tectonic regime. Moment tensor inversions reveal consistent thrusting styles, but principal stress orientations vary with depth, with σ₁ rotating from vertical in the upper crust to horizontal at tremor depths. This supports a two-layer deformation model shaped by orogenic collapse and lower crustal convergence-parallel shear. Our findings demonstrate that tremor generation in Taiwan reflects evolving stress regimes, fluid-assisted weakening, and structural heterogeneity associated with the interplay of collision, subduction, and back-arc extension. Tremors thus serve as sensitive indicators of deep-seated tectonic processes in dynamically evolving mountain belts.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231036"},"PeriodicalIF":2.6,"publicationDate":"2025-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exhumation history of the eastern Tethyan Himalaya: Evidence from Apatite (UTh)/He Thermochronology","authors":"Xu Han,&nbsp;Jin-Gen Dai,&nbsp;Bo-Rong Liu,&nbsp;Zhi-Cheng Yu","doi":"10.1016/j.tecto.2025.231035","DOIUrl":"10.1016/j.tecto.2025.231035","url":null,"abstract":"<div><div>The Himalayan orogen is an ideal natural laboratory for investigating exhumation processes due to the diverse and distinctive tectonic and climatic features. Whereas numerous low-temperature thermochronometric studies have been conducted on southern flank of the orogen (mainly in the Greater Himalaya and Lesser Himalaya), the dominant controls on exhumation remain debated due to the complex interactions between climate, topography, and tectonics. In contrast, the Tethyan Himalaya along the northern flank exhibits relatively limited recent tectonic activity and spatially uniform precipitation, which makes it more suitable for exploring controlling factors of exhumation. To reconstruct the exhumation history of the eastern Tethyan Himalaya and identify its controls, we collected bedrock samples along river channels for apatite (U<img>Th)/He dating. Low-temperature thermochronology and thermal history modeling indicate three rapid exhumation phases: ca. 10–7 Ma, ca. 6–3 Ma, and ca. 2–0 Ma. The ca. 10–7 Ma phase correlates with the Asian summer monsoon intensification, during which increased precipitation enhanced fluvial incision. The ca. 6–3 Ma phase is the last vestige of tectonically controlled rapid exhumation in Himalaya, subsequent to the decline of the India-Asia convergence rate at ca. 6 Ma. The most recent phase (&lt;2 Ma) is primarily linked to localized normal faulting. Additionally, a pronounced geomorphic contrast is observed: river valleys south of the Himalayan drainage divide exhibit significantly wider widths compared to tributaries of the upper and lower Yarlung River located north of the divide. These differences correlate with exhumation timing, as areas experiencing older exhumation phases exhibit wider valleys. This correlation suggests that fluvial erosion exerts a long-term control on exhumation patterns within the orogen.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231035"},"PeriodicalIF":2.6,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity analysis of lithospheric convergence velocity in numerical simulations of self-sustained Andean-type subduction","authors":"Jamison Assunção ,&nbsp;Boris J.P. Kaus ,&nbsp;Andrea Piccolo ,&nbsp;Nicolas Riel ,&nbsp;Victor Sacek","doi":"10.1016/j.tecto.2025.231030","DOIUrl":"10.1016/j.tecto.2025.231030","url":null,"abstract":"<div><div>Plate velocities on Earth are all on the order of several centimeters per year, despite large uncertainties in mantle rheology and plate geometry. Here, we conducted a series of 2D self-sustained Andean-type subduction simulations, and investigated how the convergence speed between an oceanic and a continental lithosphere is influenced by plate geometry, lower mantle rheology and the presence of a partial melt zone (PMZ) of relatively low viscosity under the oceanic lithosphere. We ran sets of simulations with different oceanic plate lengths at the surface (OPLS), ranging from 1000 to 5000 km. The overall subduction pattern displayed a relatively rapid acceleration of the subducting plate, followed by a deceleration of approximately the same duration until the plate reached the lower mantle. After this point, the convergence velocity tends to remain stable, varying up to 3.5 cm/yr during subduction across most of the simulated scenarios, supporting the hypothesis of sustained convergence rates for tens of millions of years. We found a linear relationship between the OPLS and the average convergence speed after the plates reach the 660-km discontinuity, with the average convergence velocity decreasing by a rate of approximately 1.3 cm/yr per each additional 1000 km of OPLS. We also tested the sensitivity of the average convergence velocity to variations in lower mantle viscosity and found that decreasing the viscosity from 1.5 × 10²² to 0.5 × 10²² Pa s increased the convergence speed of the subducting plate – after reaching the 660-km discontinuity – by up to a factor of three, hindering convergence stability. By testing the effect of a PMZ modeled via asthenospheric rheology scaling, we found that it does not significantly alter the convergence speed stability or affect the kinematics. Instead, it primarily mimics the behavior of a scenario with a smaller oceanic plate.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231030"},"PeriodicalIF":2.6,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 aggregation-diffusion effect of shallow motions in the 2022 Menyuan Mw 6.6 earthquake","authors":"Anhua Ju ,&nbsp;Haiqing Yang ,&nbsp;Xingyue Li ,&nbsp;Lixin Peng","doi":"10.1016/j.tecto.2025.231033","DOIUrl":"10.1016/j.tecto.2025.231033","url":null,"abstract":"<div><div>The dynamic processes of the Earth's surface before and after an earthquake have long been central to seismological research. However, the relationship between surface motions and seismic activity remains difficult to establish. This study proposes a novel method for quantifying the orderliness of surface motions. The method defines trend direction at each time step based on the three-dimensional displacement time series derived from Sentinel-1 SAR images from different orbits. It also describes the aggregation and diffusion effects of motion directions before and after the earthquake. Additionally, a horizontal displacement acceleration-deceleration detection model based on piecewise linear fitting identifies monthly acceleration and deceleration points throughout the seismic event. The results showed that the observable horizontal displacement was significantly larger than the vertical displacement, exhibiting the strike-slip faulting characteristics of the 2022 Mw 6.6 Menyuan earthquake. The average information entropy was 6.088 before the earthquake, dropped to 5.943 near the event, and rose to 6.067 afterward. Surface motion direction and amplitude exhibit a process of aggregation and acceleration followed by diffusion and deceleration. This indicates that geodetic techniques can detect subtle surface motion changes potentially linked to seismic preparation processes.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"920 ","pages":"Article 231033"},"PeriodicalIF":2.6,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145658139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}