Tectonophysics最新文献

{"title":"Interplay of slow-slip faults beneath Mexico City induces intense seismicity over months","authors":"Manuel J. Aguilar-Velázquez ,&nbsp;Paulina Miranda-García ,&nbsp;Víctor M. Cruz-Atienza ,&nbsp;Darío Solano-Rojas ,&nbsp;Josué Tago ,&nbsp;Luis A. Domínguez ,&nbsp;Carlos Villafuerte ,&nbsp;Víctor H. Espíndola ,&nbsp;Delia Bello-Segura ,&nbsp;Luis Quintanar-Robles ,&nbsp;Mathieu Perton","doi":"10.1016/j.tecto.2025.230659","DOIUrl":"10.1016/j.tecto.2025.230659","url":null,"abstract":"<div><div>In February 2023, a long seismic sequence began in western Mexico City causing widespread panic and some damage to housing infrastructure. On May 11 and December 14, two Mw3.2 mainshocks occurred at less than 700 m depth. Unprecedented satellite interferograms captured tectonic deformations in the two epicentral zones during the days surrounding the earthquakes. Data analysis revealed extended slip with maximum values around 8 cm on two sub-parallel east-west trending normal faults 800 m apart: namely the Barranca del Muerto (BM) fault to the south and the Mixcoac fault to the north. Detailed microseismicity analysis showed that 95 % of the slip on the BM fault was aseismic and initiated at least 6 days before the May 11 earthquake on the main asperity, located 1 km east of the hypocenter and ∼ 1.2 km deep. For the December event on the Mixcoac fault, ∼70 % of the slip was also aseismic but shallower (mostly above 600 m), which can be partially explained by the induced stresses on that fault due to the May slip on the BM fault. A quantitative geomorphological analysis allowed to establish the structural connection between both buried faults and their geomorphic expression to the west, with surface extensions of ∼3.5 and ∼ 4.5 km in the hilly area—where the most intense seismicity concentrates. The spatiotemporal patterns of fast and slow earthquakes suggest that the seismotectonics west of the city comprises two mechanically distinct zones: a stable region prone to aseismic deformation to the east where faults are buried under water-saturated sediments, and an unstable region to the west, prone to seismic radiation where faults are expressed geomorphologically. Thus, the seismic swarms in this area appear to result from the regional extensional regime, the stresses induced by slow slip on the eastern fault segments and interaction between these faults.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"902 ","pages":"Article 230659"},"PeriodicalIF":2.7,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Mapping a seismic barrier across the Shumagin Gap from satellite goce derivatives direct and inverse modeling","authors":"Orlando Álvarez ,&nbsp;Silvana Spagnotto ,&nbsp;Silvina Nacif ,&nbsp;Mario Gimenez ,&nbsp;Andrés Folguera","doi":"10.1016/j.tecto.2025.230657","DOIUrl":"10.1016/j.tecto.2025.230657","url":null,"abstract":"<div><div>The earthquake potential of the segment known as the Shumagin gap, located along the southwestern Alaska convergent margin, has been debated for over 40 years. This portion of the megathrust has not experienced a historically great earthquake with a magnitude (Mw) greater than Mw = 8.0, or at least none has been recorded in the instrumental era, exhibiting a moderate to low slip deficit. On 22 July 2020, an Mw = 7.8 thrust-fault earthquake ruptured a deeper portion of the megathrust along the eastern edge of the Shumagin Gap. Aftershocks following this event, including an Mw = 7.6 strike-slip earthquake on 19 October 2020, delineated an approximate north-south fault zone. Later, on 29 July 2021, an Mw = 8.2 thrust-fault earthquake ruptured the Semidi segment to the East. In this work, we examined the coseismic behavior of the Shumagin gap and adjacent Semidi segment along the Alaska margin from direct and inverse models obtained from satellite-derived gravity data. The distribution of the vertical gravity gradient shows a saddle point topography along the Shumagin Gap where the aftershocks of the July 2020 Mw = 7.8 earthquake concentrated in a nest. The gravity disturbance and the inverse model of mass anomalies also show an along-strike segmentation. Anomalous mass inferred along the Shumagin Gap, is consistent with the seismicity, focal mechanisms, and recently published works, suggesting that this segment hosts a seismic barrier (along-strike) that limits earthquakes with magnitudes Mw &gt; 8.0. On the other hand, an across-strike (along-dip) segmentation is inferred from Tzz, which is consistent with vertical motion models. Comparison of the interplate coupling and <em>b-values</em> distribution to the vertical gravity gradient, allowed mapping main asperities in the region suggesting that the area to the west of the Shumagin gap could host a great megathrust earthquake in the future.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"900 ","pages":"Article 230657"},"PeriodicalIF":2.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444750","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":"Assessment of uncertainty propagation within compaction-based exhumation studies using Bayesian inference","authors":"Patrick Makuluni ,&nbsp;Juerg Hauser ,&nbsp;Stuart Clark","doi":"10.1016/j.tecto.2025.230660","DOIUrl":"10.1016/j.tecto.2025.230660","url":null,"abstract":"<div><div>Exhumation plays a crucial role in shaping the evolution and distribution of resource systems in sedimentary basins, affecting mineral and energy resource exploration. Accurate exhumation estimates, derived primarily from empirical equations based on compaction and thermal datasets, are essential but are often compromised by data errors and unquantified uncertainties in model parameters. For instance, model parameters are usually assumed not to be affected by uncertainties despite varying within measurable ranges. Uncertainties from such variation can propagate and compromise the accuracy of exhumation estimates.</div><div>This study introduces a novel and refined approach to exhumation estimation using Markov Chain Monte Carlo (MCMC) methods to quantify and address uncertainties in data and model parameters. Using this approach, we developed a workflow for quantifying exhumation magnitudes and their associated uncertainties and applied it to sonic log datasets from the Canning and Bonaparte Basins. The impact of uncertainty propagation on exhumation results was assessed by examining four scenarios: assuming no uncertainty in the model or data, considering data noise without model uncertainty, considering model uncertainty without data noise, and considering model uncertainties and data noise together.</div><div>Our study yielded robust exhumation estimates in the Canning and Bonaparte Basins. Comparison with previous studies shows similarities and differences in exhumation estimates for multiple episodes, with discrepancies potentially arising from variations in exhumation models, data quality and coverage. Uncertainty propagation analysis reveals that considering data-related and model uncertainties together produces variable distributions of exhumation estimates with wider uncertainty ranges. Overall, data quality and coverage proved more critical for the accuracy and precision of exhumation estimates than model refinement. Our models can be integrated into basin evolution studies, help refine fluid migration models, and improve understanding of sedimentation and ore preservation to optimise resource exploration in sedimentary basins.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"900 ","pages":"Article 230660"},"PeriodicalIF":2.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Time-dependent stress changes associated with the 1999 İzmit (MW = 7.5) and Düzce (MW = 7.2) earthquakes in NW Türkiye: Implications for seismicity changes and earthquake hazard","authors":"Murat Utkucu ,&nbsp;Hatice Durmuş ,&nbsp;Fatih Uzunca ,&nbsp;Süleyman Sami Nalbant","doi":"10.1016/j.tecto.2025.230656","DOIUrl":"10.1016/j.tecto.2025.230656","url":null,"abstract":"<div><div>In this study, we calculated coseismic and time-dependent viscoelastic (VE) postseismic Coulomb stress changes of the 1999 İzmit (<em>M</em>_W = 7.5) and Düzce (<em>M</em>_W = 7.2) earthquakes along the North Anatolian Fault Zone (NAFZ). We assessed these changes in relation to the seismicity surrounding <em>M</em>_W ≥ 5.0 earthquakes and the selected faults and locations. Excluding the 2009–2011–2012 Simav and 2020 Kırkağaç earthquake sequences, the calculated stress changes coincided with the observed seismicity changes. Our findings suggest that stress changes from nearby <em>M</em>_W &gt; 6.0 earthquakes provided approximately 1.9 bars of stress load for the 2009 Simav earthquake, yet only a minor stress increase (about 0.07 bars) for the 2020 Kırkağaç earthquake compared to the stress decreases (about −0.3 and − 0.18 bars, respectively) caused by the 1999 mainshocks. Nevertheless, geological and seismological evidence from published studies indicates that magma-driven stress changes may have influenced occurrence of the Kırkağaç earthquake. For the 2006 Gemlik earthquake, the coseismic stress shadow was neutralized by VE postseismic stress load at its hypocenter in 2006, suggesting it may be a long-standing off-fault aftershock of the 1999 İzmit earthquake. We also identified a seismicity shutdown due to stress shadowing along the Bursa and İnegöl faults, whereas significant stress loads caused high seismic activity along the Elmalık and Bakacak faults, as well as at the Akyazı and Gölyaka locations. Additionally, stress change calculations along the Middle Strand of the NAFZ reveal that VE postseismic stresses have been generally rising since 1999, effectively reducing negative or augmenting positive coseismically imposed stress changes. Given the last ruptures of the Middle Strand in 1419 and 1556, this fault strand may be capable of producing two earthquakes in the order of <em>M</em>_W = 7.2–7.3.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"900 ","pages":"Article 230656"},"PeriodicalIF":2.7,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143422469","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":"Tomographic evidence for segmentation of the Main Himalayan Thrust in the Uttarakhand Himalaya","authors":"Jyotima Kanaujia ,&nbsp;M. Ravi Kumar ,&nbsp;Naresh Bandari ,&nbsp;R. Vijayaraghavan","doi":"10.1016/j.tecto.2025.230655","DOIUrl":"10.1016/j.tecto.2025.230655","url":null,"abstract":"<div><div>Imaging the Main Himalayan Thrust (MHT) along and across the strike of the Himalaya is critical to understand seismogenesis and earthquake hazard. This study investigates the 3D P and S velocity structure of the Garhwal-Kumaon Himalaya (GKH) using travel times of 846 local events recorded at 54 broadband stations. Depth sections of the velocity anomalies capture the flat-ramp-flat structure of the MHT. The MHT is expressed as a low-velocity layer, possibly due to dehydration of sediments. Also, the geometry of the MHT seems distinctly different in the Garhwal and Kumaon segments. It is steeper with a narrow width in the former and gentler with a larger width in the latter. The width of the MHT is ∼60 km in Garhwal and ∼ 85 km in Kumaon. However, if the whole MHT is assumed as a locked zone, its width from the Main Frontal Thrust to the 3.5 km elevation contour in the Higher Himalaya is ∼115 in the former and ∼ 130 km in the latter. The MHT in Garhwal has a 30 km wide shallow ramp (∼2°) in the upper flat attached to a ∼ 30° steeply dipping 10 km wide ramp, which merges with a lower flat at a depth of ∼20 km beneath the Main Central Thrust(MCT). Such a flat-ramp-flat geometry is not evident in Kumaon, with the MHT remaining flat. Also, the subsurface structures and earthquake depths beneath the MCT differ in these segments, with a varying thickness of the low-velocity layer. Relocation of earthquakes using the 3D tomographic model reveals a dominant (85–90 %) occurrence in the upper crust. The seismicity is found to straddle within a narrow zone of 30–50 km around the MCT. While the seismicity belt is mostly to the south of MCT in Kumaon, it is along and north of it in Garhwal. Deeper seismicity in Garhwal sub-Himalaya seems associated with the deep-seated Delhi Haridwar Ridge (DHR) transverse to the strike of Himalaya.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"900 ","pages":"Article 230655"},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437712","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":"Characterization of seismogenesis beneath the Tripura Fold Belt and its adjoining areas of Northeast India","authors":"Ajay Pratap Singh ,&nbsp;Om Prakash Singh ,&nbsp;Ram Bichar Singh Yadav ,&nbsp;Om Prakash Mishra","doi":"10.1016/j.tecto.2025.230658","DOIUrl":"10.1016/j.tecto.2025.230658","url":null,"abstract":"<div><div>In this study, a comprehensive analysis comprising the relocation of ∼400 well-located earthquakes (M ≤ 4.9) recorded during 2013–2015 and 19-moment tensor solutions has been made. The earthquakes were recorded by 20 seismographic stations belonging to the Geological Survey of India (GSI) and National Centre for Seismology (NCS) networks. Then, the results are corroborated with the geophysical and geological investigations for the areas that need better characterization of the seismotectonics beneath the Tripura Fold Belt (TFB) and its adjoining areas in Northeast (NE) India. The sparse seismicity distribution associated with TFB shows north-south trending anticlinal ridges and synclinal valleys. These structures decrease progressively towards the south and are confined to depths between 40 and 60 km. The mixed mode of faulting at various depths indicates significant structural heterogeneity beneath TFB that dictates the earthquake strength. We conspicuously relocated earthquakes in a cluster along the Sylhet fault (SF) with a dominant northeast striking, suggesting the presence of differential structural heterogeneities with variable strengths of earthquakes located at varying depths, which in turn indicates that the seismogenesis beneath the Sylhet fault is associated with thrust mode of faulting with distinct slip component during the processes of the rupture initiation. Moment tensor solution of the area inferred two main directions: NNE –SSW and WNW – ESE, suggesting two compressive forces acting in the study area. The NNE-SSW compressional stress is dominant in this zone. This study provides deep insights into the two different structural entities, TFB and SF of NE India, that can have the potential to contribute significantly for assessing the earthquake risk potential of the region.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"901 ","pages":"Article 230658"},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465433","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":"Tectonic evolution of the Atlantic rift, central sector offshore Uruguay","authors":"Marmisolle Josefina ,&nbsp;Morales Ethel ,&nbsp;Rossello Eduardo ,&nbsp;Soto Matías ,&nbsp;Javier Hernández-Molina","doi":"10.1016/j.tecto.2025.230654","DOIUrl":"10.1016/j.tecto.2025.230654","url":null,"abstract":"<div><div>The Uruguayan Continental Margin (UCM) is considered one of the most promising frontier areas for hydrocarbon exploration in the South Atlantic. The UCM central sector, corresponding to the transitional region between the Punta del Este and Pelotas basins and where the Rio de la Plata Transfer System (RPTS) is located, exhibits outstanding characteristics such as interruption of the seaward dipping reflectors (SDRs), dislocation of magnetic and gravity anomalies and depocenters, and hyper-thinning of the continental crust. Owing to these characteristics, this sector is a key area for understanding the evolution of the margin during the Atlantic opening and evaluating the real potential of the UCM to contain hydrocarbon accumulations. This study demonstrates the results of a new subsurface mapping method using 2D and 3D seismic data in the central sector of the UCM. Structural interpretations have led to the definition of i) a NW-oriented hyperextended region located where the SDRs are interrupted, characterized by a shallow Moho (˂3 km); ii) a set of NW-SE oriented transtensional faults, some of which reach the Moho, which has delineated a series of discrete grabens; and iii) a Barremian-Aptian depocenter with a rhomboidal geometry, exhibiting the greatest thickness over the hyperextended crust region. The central sector of the UCM concentrates on the extensional processes associated with the breakup of Western Gondwana, which controlled the initial phase of the Atlantic opening in this region. The sinistral transcurrent nature of the RPTS plays a crucial role in generating the transtensional stress field in an extensive regional context. This process reactivates basement-inherited structures with a general NW-SE orientation, leading to the formation of subsidence areas. The proposed new tectonic model will contribute to the knowledge of the hydrocarbon potential of the UCM.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"899 ","pages":"Article 230654"},"PeriodicalIF":2.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420999","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":"Crustal magnetic structure and implications for the Eastern Himalayan Syntaxis revealed by EMAG2-v3","authors":"Liguo Jiao ,&nbsp;Jiyao Tu ,&nbsp;Yu Lei ,&nbsp;Junhao Zhao ,&nbsp;Weinan Wang","doi":"10.1016/j.tecto.2024.230608","DOIUrl":"10.1016/j.tecto.2024.230608","url":null,"abstract":"<div><div>The Eastern Himalayan Syntaxis (EHS) is located at the forefront of the collision between the Indian and Asian plates, representing the region with the most rugged terrain and intricate structural deformations along the southeastern margin of the Tibetan Plateau. A long-standing debate has revolved around two modes of tectonic evolution: “flat slab indentation” and “tectonic aneurysm”. This study, employing analysis and inversion of the EMAG2-v3 crustal magnetic anomalies, has obtained a 3D crustal magnetic structure. By integrating magnetic structures with rock susceptibilities, the rough crustal lithological structure is determined, and a simplified two-stage evolution model is established. The results reveal the presence of a strong magnetic body in the core of the EHS, particularly in the region of Namche Barwa Peak and Gyala Peri Peak. The 3D spatial characteristics of this strong magnetic body indicate that deep-seated materials beneath the EHS are uplifting from the plateau interior to the southeast. Both crustal magnetic and lithological structures support the “tectonic aneurysm” evolution model. The seismic hazard zone is identified as the region surrounding the boundary of strong magnetic body, particularly on the side adjacent to the strong magnetic body, with Namche Barwa Peak and Gyala Peri Peak as its center.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"896 ","pages":"Article 230608"},"PeriodicalIF":2.7,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867475","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":"Lithospheric flexure and effective elastic thickness under the Ulleung Basin in the East Sea using gravitational coherence","authors":"Masume Akbari ,&nbsp;Hojjat Kabirzadeh ,&nbsp;Chang Hwan Kim ,&nbsp;Chan Hong Park ,&nbsp;Youn Soo Lee ,&nbsp;Jeong Woo Kim","doi":"10.1016/j.tecto.2024.230609","DOIUrl":"10.1016/j.tecto.2024.230609","url":null,"abstract":"<div><div>To estimate a non-uniform effective elastic thickness (<span><math><msub><mi>T</mi><mi>e</mi></msub></math></span>) of lithosphere across Korean Peninsula and the Surrounding Seas (KPSS), we employ gravitational coherence analysis between gravity anomalies and topography/bathymetry data in the Fourier domain. Exploring crustal flexure and effective elastic thickness variations can offer insights into flexural strength, and evolutionary mechanics of the lithosphere under Ulleung Basin (UB). Our approach involves two scenarios: a large study area spanning the KPSS, and a more targeted investigation focused on UB. Dividing the study area into overlapping windows enables us to recover non-uniform <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span> values over the targeted regions. The UB study area is divide to 200 km by 200 km windows, and KPSS is divided to 400 km, 600 km, and 800 km windows to recover both short wavelengths and long wavelengths of <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span>. Our results reveal a <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span> range of 843 km for KPSS and recovered <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span> range from 1 to 10 km for UB. The estimated elastic thickness values in southern part of this basin are smaller compared to central and northern parts. These findings are consistent with prior estimations and comparative studies within the region, improving the understanding of UB's lithospheric properties. The recovered <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span> values for UB (<span><math><msub><mi>T</mi><mi>e</mi></msub><mo>&lt;</mo><mn>6</mn><mspace></mspace><mi>km</mi></math></span>) suggests a young and weak oceanic lithosphere under this region. The alignment between recovered <span><math><msub><mi>T</mi><mi>e</mi></msub></math></span> configuration and tectonic features in KPSS displays a large-scale lithospheric structure.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"896 ","pages":"Article 230609"},"PeriodicalIF":2.7,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"1-D velocity model from local earthquake localization and receiver functions for the southern Neuquén basin: Insights into lithosphere structure and dynamics","authors":"Sebastian Correa-Otto ,&nbsp;Silvana Spagnotto ,&nbsp;Guido M. Gianni ,&nbsp;Mario Giménez","doi":"10.1016/j.tecto.2024.230602","DOIUrl":"10.1016/j.tecto.2024.230602","url":null,"abstract":"<div><div>Knowledge of the lithospheric structure is key to understanding the seismotectonic characteristics of convergent margins. In this study, we provide a robust one-dimensional velocity model for the Añelo region, located within the Neuquén extensional basin in Argentina, with the aim of illuminating the lithospheric characteristics of the back-arc region of the southern central Andes. Data from a temporary network of broadband stations operational from October 2014 to March 2020 was utilized. We employed two distinct seismological techniques for obtaining models with varying resolutions at multiple scales and depths. On the one hand, upper thin layers were obtained by the inversion of a model based on hypocenters from local earthquakes, and on the other, we calculated receiver functions to estimate thicker and deeper layers. By combining both methods we were able to obtain a joint and accurate velocity model, a crucial tool for conducting seismicity studies in the region and achieving precise determinations of earthquake locations. Moreover, the analysis of velocity variations offers valuable insights into the complex lithospheric structure beneath the study area, shedding light on the poorly understood seismotectonic activity in the Andean retroarc. We suggest that the presence of a weakened or hot lithospheric mantle beneath the southern Neuquén Basin may be linked to the Payenia mantle anomaly. This anomaly likely softens the upper plate, concentrating deformation and intraplate seismicity, as documented in the vicinity of the study area.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"896 ","pages":"Article 230602"},"PeriodicalIF":2.7,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143100109","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}