Silvina Nacif , Martin Schimmel , Andrés Nacif , Laura Godoy , Marianela Lupari , Renzo Furlani , Mario Gimenez , Andrés Folguera
{"title":"Insights into the crustal and the magmatic feeding structure at the Payunia Volcanic Province highlighted by geophysical methods, in the retroarc of the Southern Central Andes","authors":"Silvina Nacif , Martin Schimmel , Andrés Nacif , Laura Godoy , Marianela Lupari , Renzo Furlani , Mario Gimenez , Andrés Folguera","doi":"10.1016/j.jog.2024.102059","DOIUrl":"10.1016/j.jog.2024.102059","url":null,"abstract":"<div><div>The Payunia Volcanic Province is a Quaternary volcanic plateau emplaced in the retroarc area in the northern Neuquén Mesozoic Basin, associated with a hydrocarbon system. At deeper levels, this basin is linked to different intrusive systems that developed in the retroarc region at different times, during the Jurassic, Cretaceous, Eocene, Miocene, and even the Quaternary which influenced the hydrocarbon system maturity. We analyzed the Moho structure through this retroarc region, as well as the crustal structure affected by different stages of regional extension. From continuous seismic noise data, we calculated the autocorrelograms to obtain the reflection response below each seismological station. This allowed imaging the surface of primary crustal reflectors and in a few stations the top of an asthenospheric anomaly (SWAP) found by magnetotelluric survey and in concordance with satellite magnetic data. The crustal reflectors were identified in all stations at a mean two-way travel time of about ∼8.5 s and ∼12.5 s using frequency bands of about 1.0–2.4 Hz. Therefore, this is the first geophysical research that estimates the depth of the magmatic system, hosted at the top of the lower crust and the Moho discontinuity. The deepest reflector, only recognized in 4 stations, was observed with a two-way travel time of 17.2 s to 19.6 s. We used a mean one-dimensional Vp model to obtain the corresponding reflector depths which constrain the two-dimensional forward gravity model that fits with the observed regional anomaly for the region. We finally established a relationship between the shallowest sublithospheric electrical conductivity anomalies determined in previous researches and the strong deep reflections observed in some of the seismological stations. This information may help to constrain geochemical and petrological models and re-evaluate the hydrocarbon system maturity of the northern Neuquén basin.</div></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"162 ","pages":"Article 102059"},"PeriodicalIF":2.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142318907","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}
Tarik El Moudden , Mohamed Amnai , Ali Choukri , Youssef Fakhri , Gherabi Noreddine
{"title":"Artificial intelligence for assessing the planets' positions as a precursor to earthquake events","authors":"Tarik El Moudden , Mohamed Amnai , Ali Choukri , Youssef Fakhri , Gherabi Noreddine","doi":"10.1016/j.jog.2024.102057","DOIUrl":"10.1016/j.jog.2024.102057","url":null,"abstract":"<div><div>Questions about interconnection possibilities between planets’ positions and seismic events on the earth have emerged recently in TV channels, social media, etc. In this study, an Artificial Neural Network (ANN) and Random Forest Regression (RFR) are used to predict the number of earthquakes that can occur on Earth, depending on the Earth’s position relative to other planets and solar positions. Our new integration dataset contains 9809 observations and nine features firstly from the global earthquake archive, which is an authoritative layer by Esri, and secondly from the accurate data web portal “theskylive.com.”.</div><div>The results obtained from RFR and ANN prove the partial influence of planets positions on sesimic activity on the earth. In other words, quantitatively through the ANN that gets an accuracy of 68.27 %, MAE of 5.36, MSE of 52.78, RMSE of 7.26, R-Squared of 0.65, and also through the RFR that gets an accuracy of 65.06 %, MAE of 5.60, MSE of 58.21, RMSE of 7.63, R-Squared of 0.67, prove the partial influence on one hand. Qualitatively through the curve of the training phase of the ANN, which is a decreasing and convex function, reinforces the aforementioned proof on the other hand. For these reasons, it can be deduced that there is a possible connection between tectonic stress triggers and the positions of the planets in the solar system. Our dataset was uploaded to the github(<span><span>https://github.com/mouddentarik/Earthquake01</span><svg><path></path></svg></span>.) as well as the code will be publicly available at the github(<span><span>https://github.com/mouddentarik/PythonCode_Earthquakes-</span><svg><path></path></svg></span>.) to share our results.</div></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"162 ","pages":"Article 102057"},"PeriodicalIF":2.1,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311062","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}
Emő Márton , Vesna Cvetkov , Miodrag Banješević , Gábor Imre , Aleksandar Pačevski
{"title":"Tectonic evolution of the Circum-Moesian orocline of the Carpatho-Balkanides: Paleomagnetic constraints","authors":"Emő Márton , Vesna Cvetkov , Miodrag Banješević , Gábor Imre , Aleksandar Pačevski","doi":"10.1016/j.jog.2024.102058","DOIUrl":"10.1016/j.jog.2024.102058","url":null,"abstract":"<div><p>The areas of the present study in eastern Serbia, the Danubicum and the Timok Magmatic Complex (TMC, part of the Geticum) are situated between the Vardar Zone and Moesia. The first is Moesia derived and thrust over the Geticum during the latest Cretaceous, the second represents the central segment of the subduction related Apuseni-Banat-Timok-Srednogorie (ABTS) metallogenic belt. The new results, based on 18 geographically distributed sampling points (228 field oriented drill cores) imply large CW vertical axis rotations for the Upper Jurassic (Lower Cretaceous) carbonates of the Danubicum and a moderate one for the Upper Cretaceous igneous and sedimentary rocks from the TMC. These, together with earlier published paleomagnetic data provide kinematic constraints to test the circum-Moesian backarc-convex orocline model. The strike test plot clearly documents that it is a progressive arc. The starting situation at the time of the volcanic activity in the metallic belt (90–70 Ma) must have been a generally E-W oriented S segment, continuing in NNW-SSE oriented ABT segments. The present geometry of the circum-Moesian belt, in the context of Miocene paleomagnetic results from the Vardar Zone and the Apuseni Mts, is interpreted as the result of two main tectonic processes. The first is an about 30° vertical axis CW rotation which took place in coordination with the Vardar Zone (20–17 Ma). The second is an additional 40–65° CW rotation (17–15 Ma) involving also the Danubicum, due to the subduction pull of the E Carpathians in combination with the corner effect of Moesia.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"162 ","pages":"Article 102058"},"PeriodicalIF":2.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0264370724000413/pdfft?md5=059f99b466aba115078c6ffd6c917589&pid=1-s2.0-S0264370724000413-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142239374","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":"Special Issue on “Seismic anisotropy – from rock samples to large-scale imprints in the lithosphere-asthenosphere system”","authors":"","doi":"10.1016/j.jog.2024.102042","DOIUrl":"10.1016/j.jog.2024.102042","url":null,"abstract":"","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102042"},"PeriodicalIF":2.1,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141546687","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":"Limited sensitivity of Antarctic GIA mass change estimates to lateral viscosity variations","authors":"Yoshiya Irie , Jun’ichi Okuno , Koichiro Doi , Takeshige Ishiwa , Yoichi Fukuda","doi":"10.1016/j.jog.2024.102047","DOIUrl":"10.1016/j.jog.2024.102047","url":null,"abstract":"<div><p>The Gravity Recovery and Climate Experiment (GRACE) has revealed spatiotemporal mass changes in the Antarctic Ice Sheet. However, GRACE data must be corrected for the gravity changes due to glacial isostatic adjustment (GIA). Here we investigate the sensitivity of GIA-induced gravity changes in Antarctica to the lithospheric thickness and upper mantle viscosity using a one-dimensional (1-D) model that assumes a radially varying Earth structure. The sensitivity is assessed using several Antarctic ice-history models that have been widely used to correct GRACE data. The results indicate a trade-off between lithospheric thickness and upper mantle viscosity in evaluating the Antarctic GIA correction. This trade-off exists for all ice-history models; however, the reason for the trade-off differs among models. Furthermore, since there is a sharp contrast in the Earth structure between West and East Antarctica, the adopted ice histories are separated into West and East Antarctic components to examine their contributions to the Antarctic GIA correction. We consider 1-D Earth structures that are averaged from the seismically derived three-dimensional Earth structure for West and East Antarctica. These results indicate that the contributions of the East and West Antarctic loads do not significantly affect the GIA corrections for the West and East Antarctic regions, respectively, and that the trade-off between lithospheric thickness and upper mantle viscosity results in minimal divergence in the assessment of the Antarctic GIA correction between the averaged Earth models of West and East Antarctica. Therefore, the contrast in Earth structure beneath Antarctica may have a limited effect on the ice-mass change estimates for the entire Antarctic Ice Sheet.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"162 ","pages":"Article 102047"},"PeriodicalIF":2.1,"publicationDate":"2024-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136875","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}
Chiara Montomoli , Salvatore Iaccarino , Gianfranco Di Vincenzo , Pierre Lanari , Alessandro Petroccia , Rodolfo Carosi
{"title":"Deformation and pressure-temperature-time history of the External Tuscan Units in the Northern Apennines (Italy): The case of the Punta Bianca Unit","authors":"Chiara Montomoli , Salvatore Iaccarino , Gianfranco Di Vincenzo , Pierre Lanari , Alessandro Petroccia , Rodolfo Carosi","doi":"10.1016/j.jog.2024.102045","DOIUrl":"10.1016/j.jog.2024.102045","url":null,"abstract":"<div><p>In this study we investigated through a multidisciplinary approach the still poorly known tectono-metamorphic evolution of the Punta Bianca Unit in the Northern Apennines. The Punta Bianca Unit is part of the Tuscan Metamorphic Units, a group of units derived from the Adria passive margin, metamorphosed at different conditions, and forming the backbone of the Northern Apennine belt. We combined meso- and microstructural analyses, <sup>40</sup>Ar/<sup>39</sup>Ar white-mica geochronology and multi-equilibrium geothermobarometry from high-resolution X-ray chemical maps, to unravel the deformation and metamorphic history of this part of the belt. Meso- and microstructural data indicate that the Punta Bianca Unit recorded two main phases of ductile deformation (here referred to D<sub>p-1</sub> and D<sub>p</sub>) associated with syn-kinematic growth of K-white mica, chlorite, calcite, quartz on the related tectonic foliations (S<sub>p-1</sub> and S<sub>p</sub>), followed by a later ductile deformation phase (D<sub>p+1</sub>) lacking of metamorphic blastesis. <em>P-T</em> estimates complemented by microstructural data suggest that peak metamorphic conditions reached ∼0.8 GPa and ∼350°C and occurred synchronously with the first deformation phase (D<sub>p-1</sub>). Temperature values were also confirmed by Raman spectroscopy of carbonaceous material on selected samples. This stage was followed by the exhumation of the Punta Bianca Unit, as testified by decreasing pressure and temperature down to ∼0.4 GPa and ∼300°C respectively, together with the development of the main foliation (S<sub>p</sub>). At the regional scale, the Tuscan Metamorphic Units have been mostly affected by <em>HP-LT</em> metamorphic gradients equilibrated under blueschist-facies conditions (up to ∼1.4 GPa). Results from the present work on the contrary, suggest that the Punta Bianca Unit never reached such <em>HP-LT</em> conditions, testifying that it was deformed at relatively upper structural levels, thus highlighting an important variation in the tectono-metamorphic evolution of the Tuscan Metamorphic Units along strike in the Northern Apennines. <sup>40</sup>Ar/<sup>39</sup>Ar laserprobe data (using both the in-situ and step-heating techniques) indicate a minimum age for the onset of continental subduction of ∼20 Ma (D<sub>p-1</sub>), which was followed in close succession by exhumation at ∼16 Ma. This approach, if applied to different tectonic units building up the nappe pile of the Northern Apennines, could be successful in better unravelling the tectonic history.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102045"},"PeriodicalIF":2.1,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141954095","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":"Patchwork structure of continental lithosphere captured in 3D body wave images of its anisotropic fabrics","authors":"Jaroslava Plomerová","doi":"10.1016/j.jog.2024.102041","DOIUrl":"10.1016/j.jog.2024.102041","url":null,"abstract":"<div><p>This paper presents an overview of research conducted for more than five decades around Vladislav Babuška and collaborators on large-scale seismic anisotropy in tectonically different regions of continental lithosphere in Europe. A wide range of independent data sets and methods are covered. It also briefly touches laboratory measurements of velocity anisotropy on rock samples from the crust and the upper mantle, and emphasizes the importance of considering anisotropy in studies of the Earth structure. The anisotropy is responsible for even larger velocity variations than those due to composition of the most abundant upper mantle rocks (peridotites). The large-scale in-situ measurements of the upper mantle anisotropy capture fabrics of the mantle lithosphere, and enables mapping lateral changes in its structure. The joint inversion/interpretation of the teleseismic body-wave anisotropic parameters, such as variations of directional terms of relative travel time residuals of P waves, shear-wave splitting or the coupled anisotropic-isotropic teleseismic P-wave tomography, image the continental lithosphere as a mosaic of anisotropic domains. Each of the domains has its own thickness and fossil fabric characterized by tilted symmetry axes. We map boundaries of the domains in dependence on the fabric changes. The boundaries can be either narrow and steep or broader and inclined, with an offset relative to boundaries of the related crustal bocks, which can reach several tens of kilometres. This overview presents the European lithosphere-asthenosphere boundary (LAB) and shows examples of anisotropic fabrics of the mantle lithosphere domains and their boundaries in different parts of the European plate.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102041"},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0264370724000243/pdfft?md5=ed1b60fa3cbd085f1369a8c8a17eb9a0&pid=1-s2.0-S0264370724000243-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141845808","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}
Muskan Nazir Dar, Bikram Singh Bali, Sareer Ahmad Mir, Ahsan Afzal Wani
{"title":"Fault system dynamics of the Kashmir, NW Himalaya, India using continuous GPS observations and geomorphic evidences","authors":"Muskan Nazir Dar, Bikram Singh Bali, Sareer Ahmad Mir, Ahsan Afzal Wani","doi":"10.1016/j.jog.2024.102044","DOIUrl":"10.1016/j.jog.2024.102044","url":null,"abstract":"<div><p>We collected data from the continuous Global Positioning System (cGPS) sites across the Kashmir Valley, situated at latitude 34<sup>◦</sup>N, spanning from 2008 to 2021. Inter-site velocities define a region of approximately 15,000 km<sup>2</sup> with broadly distributed strain accumulation at −7.22×10<sup>−8</sup> nano strain/year (compression component) and the maximum shear strain γ<sub>max</sub> of 1.9051×10<sup>−7</sup> nano strain/year. The estimated site velocity in the ITRF14 ranges between 30.5±1–42.85±3 mm/yr. It was observed that the average deformation rate of the GPS sites in the Kashmir region ranges between 2.86±1–15.47±3 mm/yr relative to the India fixed reference frame, suggesting a predominant N-S directed compressional tectonic regime. The focal mechanism solutions of the earthquakes in and around the Kashmir Valley suggest dominant thrust faulting followed by normal faulting. Analysis of the vertical component of the GPS time series shows that the northwest segment of the valley subsides at the rate of −1.71± 0.70 mm/yr, while the southeast segment uplifts at the rate of 5.4 ± 0.5 mm/yr. In addition to vertical component, we observed differential movement of the sites relative to IISC site on the northwest and southeast segments. The rate of baseline change of the GPS sites indicates 7.30 ± 0.75 mm/yr extension in SE-NW direction and −5.32 ± 0.75 mm/yr NE-SW compression across and along the Kashmir Valley. Geodetic observations reveal a transition that aligns with the Magam lineament/fault previously identified by Ganju and Khar (1984) using gravity and magnetic data. The observation was supported by the field investigations and remote sensing techniques, confirming the existence of Magam Fault. During the field investigations, various geomorphic expressions of fault were observed, including fault ruptures, fault scarps, offset ridges, deflected drainages/rivers, linear alignment of springs, linear drainage lines, triangular facets and offset Recent sedimentary deposits (Karewas) were observed. The field evidence suggests exposure of normal faults at Kondabal, Nasrullapora, Biru and Radbugh. These exposed extensional structures, trends in NE-SW direction and dip in NW direction with varying offset and dip amount. GPS observations supplemented by geomorphic evidences infer the presence of normal fault ̴ 80 Km extending from northeast to southwest.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102044"},"PeriodicalIF":2.1,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639285","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}
Yanchao Gu , Jun Huang , Lingyan Xiong , Feilong Huang , Yong Su , Yu Lei , Hongbo Yuan
{"title":"An investigation of ocean mass budget in the East China Sea during the GRACE era","authors":"Yanchao Gu , Jun Huang , Lingyan Xiong , Feilong Huang , Yong Su , Yu Lei , Hongbo Yuan","doi":"10.1016/j.jog.2024.102043","DOIUrl":"https://doi.org/10.1016/j.jog.2024.102043","url":null,"abstract":"<div><p>The Gravity Recovery and Climate Experiment (GRACE) mission provides uniquely high-precision observations for monitoring ocean mass changes (OMC), allowing for the establishment and evaluation of the ocean mass budget in conjunction with satellite altimetry and temperature and salinity observations. However, it is challenging to perform OMC closed-loop validation in the East China Sea (ECS) due to potential biases in the individual model and the lack of certain data processing. In this study, we comprehensively analyze the ocean mass budget in the ECS during the GRACE era (2005–2015) by utilizing multiple datasets, mainly consisting of three official GRACE RL06 solutions, three altimetry products, and four ocean reanalysis products. The effect of ocean bottom deformation, neglected in previous studies, is −0.38 ± 0.06 mm/yr, and we estimate a more accurate ensemble sea level change to be 4.05 ± 1.50 mm/yr in the ECS from the altimetry products. There are discrepancies between leakage-corrected GRACE OMC observations and steric-corrected altimeter OMC estimations in both the seasonal signals and the long-term trends (e.g., 6.25 mm/yr vs. 4.22 mm/yr). These discrepancies are strongly correlated with sediment runoff from the Yangtze River and in-situ sediment observations, suggesting that ocean sediment accumulation should be considered in the ocean mass budget in the ECS. Since in-situ sediment data are estimated over ∼100 years, we employ an empirical estimation method to determine the corresponding data during the period 2005–2015, to avoid potential biases caused by inconsistencies in observational timespans. The results show that sediment mass changes can explain about 96 % of residual trends. Our results emphasize the significant impact of sediment on improving the ocean mass budget in the ECS, offering a novel perspective for estimating ocean mass changes in other coastal regions.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102043"},"PeriodicalIF":2.1,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141592965","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}
Yuan Li , Xia Liu , Anfu Niu , Wei Zhan , Long Feng , Zheng Tang
{"title":"Numerical simulation of fault activity in the Qilian tectonic belt and dynamic background of Menyuan earthquake series","authors":"Yuan Li , Xia Liu , Anfu Niu , Wei Zhan , Long Feng , Zheng Tang","doi":"10.1016/j.jog.2024.102034","DOIUrl":"https://doi.org/10.1016/j.jog.2024.102034","url":null,"abstract":"<div><p>Some faults in the Qilian tectonic belt are seismogenic areas for strong earthquakes, including the western section of the Lenglongling fault, which frequently occures moderate-strong Menyuan earthquakes. In this study, using GPS velocity data of 1991–2015 as the boundary constraints, a three-dimensional viscoelastic finite element dynamic model is constructed by comprehensively considering the regional dynamic environment, crust-mantle transverse-longitudinal inhomogeneity, and spatial spreading of a complex fault system. The objective is to investigate the long-period characteristics of fault movement and stress change in the Qilian tectonic belt caused by tectonic loading, and to discuss the seismogenic conditions of the Menyuan earthquakes. The results show that the annual change of long-period movement and stress of the major faults in the Qilian Mountain tectonic zone are characterized by significant segmentation. Due to its unique geometric bend morphology, the western section of Lenglongling fault has a low movement rate, significant slip deficit and high shear stress accumulation, which are conducive to the gestation and occurrence of earthquakes. Furthermore, the seismogenic area of the Menyuan earthquake series is jointly subjected to NE-SW compressive and NW-SE tensile stress fields, and the maximum shear stress and elastic strain energy accumulate faster than in the surrounding areas. Overall, the western section of the Lenglongling fault has a strong dynamic background and favorable conditions for the frequent occurrence of the Menyuan earthquake series.</p></div>","PeriodicalId":54823,"journal":{"name":"Journal of Geodynamics","volume":"161 ","pages":"Article 102034"},"PeriodicalIF":2.3,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141095894","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}