Tectonophysics最新文献

{"title":"Seismic reflection analysis of the Western Sichuan Basin: Implications for the decoupling relationship between deep and shallow structures","authors":"Shan Yan ,&nbsp;Yang Li ,&nbsp;Zhongquan Li ,&nbsp;Gen Li ,&nbsp;Yigui Han","doi":"10.1016/j.tecto.2025.230626","DOIUrl":"10.1016/j.tecto.2025.230626","url":null,"abstract":"<div><div>The structural relationship between the deep and shallow structures of the Western Sichuan Basin (WSB) holds significant information for comprehending the tectonic framework of the basin and the eastward expansion of the Tibetan Plateau. Although the regional structural geometries in the WSB have been extensively studied, the kinematics and controlling factors are still debated. Field observations, seismic reflection profiles, and balanced sections hereby were used to quantitatively analyze the structural geometry and kinematic characteristics of the WSB and to estimate the structural shortening of major tectonic units, respectively. Combined with near-surface geological data, the seismic reflection profiles reveal a set of tectonic patterns decoupled vertically. The deep layer is characterized by stable marine sediments and Neoproterozoic basement rifts bounded by deep faults, while the shallow layer primarily comprises a distinct foreland basin consisting of a series of anticlines and thrust faults. The Middle Triassic evaporites, as the decollement layer of the decoupled tectonic patterns, regulated the deformation of the shallow asymmetrical anticlines and long-distance thrust faults, forming a typical thin-skinned structure. The balanced sections have confirmed a pattern of structural wedges with thrust faults in the shallow layers of the WSB, revealing that deformation propagation attenuates from the Longmenshan Thrust Belt (LMSTB) to the eastern part of Longquanshan (with a shortening rate &lt; 5 %). The primary contribution to this deformation is attributed to the LMSTB and the Xiongpo anticline. The joint seismic sections show that the distribution of the Triassic decollement layer gradually contracts from southwest to northeast, indicating a decrease in the intensity of stress regulation. On the basis of the spatio-temporal framework, we argue that the mechanism of the complex structural configuration in the WSB is controlled by the Middle Triassic decollement layer and exhibits different characteristics in deep and shallow structures.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230626"},"PeriodicalIF":2.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989058","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":"Geological and geodetical vertical deformation profiles across the Kuradake fault group, Central Kyushu, SW Japan: Estimation of the proportion of triggered aseismic slip in the total late Quaternary slip","authors":"Tabito Matsu'ura ,&nbsp;Kazuya Ishitsuka","doi":"10.1016/j.tecto.2025.230625","DOIUrl":"10.1016/j.tecto.2025.230625","url":null,"abstract":"<div><div>We investigated the Kuradake fault group, which includes the Matoishi-bokujo-I (MbI), Tsumushi-yama (Ty), and Matoishi-hatabe-III (MhIII) faults, on the northwestern rim of Aso caldera, SW Japan. To obtain the total vertical displacement since ca. 87 ka, we conducted a geological survey, borings, and seismic profiling, and to obtain the vertical displacement due to slip triggered by the 2016 Kumamoto earthquake (<em>Mw</em> = 7.0 on 16 April 2016), we conducted interferometric synthetic aperture radar (InSAR) monitoring. In 10 arrayed borings along survey section Krdk 21 across the fault group, we recognized pre-Aso-2 (age unknown), Aso-2 (146 ka), Aso-3 (133–120 ka), and Aso-4 (ca. 87 ka) tephras, and additional pyroclastic flow/fall deposits. We reconstructed the Aso-4 flow depositional surface by subtracting the cover sediment thickness and estimated normal slips of 18–20 m and 15 m on the Ty and MbI faults, respectively. Triggered aseismic normal slips on the MhIII, Ty, and MbI faults during the 2016 earthquake determined by InSAR monitoring were 5–15, 13–15.5, and 14–21.5 cm, respectively. The slip amounts on the Ty and MbI faults are not compatible between the geological and geodetical observations. Further, because the geologically observed dextral slip component on the Ty fault was not observed by the InSAR monitoring, the observed slip on that fault is not related to 2016 event. Based on the geodetical slips on the Ty and MbI faults and the recurrence interval (2 ky) of the 2016 source (Futagawa fault) reported by paleoseismic studies, total vertical displacement since 87 ka was 5.7–6.8 m and 6.2–9.5 m, respectively, accounting for ≥ 29–38 % and ≥ 41–63 %, respectively, of the geological vertical displacement of the Aso-4 surface. The geologically expected oblique and additional normal slips on the Ty and MbI faults can account for the residual displacements.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"898 ","pages":"Article 230625"},"PeriodicalIF":2.7,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143140835","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":"Stress evolution on the Kunlun fault under the influence of the laterally heterogeneous lower crust","authors":"Yajin Pang,&nbsp;Yanqiang Wu,&nbsp;Changyun Chen","doi":"10.1016/j.tecto.2025.230615","DOIUrl":"10.1016/j.tecto.2025.230615","url":null,"abstract":"<div><div>The Kunlun fault is seismically active with successive strong earthquakes. Two seismic gaps along the fault that have not ruptured for several centuries, including the Xidatan and Maqin-Maqu segments, provoke urgent concerns on future seismic hazard. Quantitative analysis of crustal stress evolution, which is controlled by inter-seismic tectonic loading and strong earthquakes, is important for understanding the faulting interactions and estimating future seismic hazard. Here, we construct a 3D viscoelastic finite element model to calculate crustal stress evolution on the Kunlun fault, especially the two seismic gaps. The effects of far-field tectonic loading, inter-seismic fault creep in ductile shear zone, and historical strong earthquakes are analyzed. A series of comparative tests are conducted to analyze the impacts of laterally heterogeneous lower crustal viscosities on faulting stress evolution. Our numerical results show that far-field tectonic loading and inter-seismic fault creep in ductile shear zone lead to Coulomb stress increases at the rates up to 3.0 kPa/yr on the Kunlun fault. The strong earthquakes surrounding the fault induced Coulomb stress increases greater than 20 kPa on the seismic gaps. In addition, lower viscosity in the lower crust of the Baryan Har block and Qiangtang block leads to less stress accumulations on the brittle fault zone in response to far-field tectonic loading and inter-seismic fault creep, but larger post-seismic Coulomb stress changes induced by strong earthquakes. The earthquake recurrence time increases from west to east, corresponding to the spatial variations of the fault slip rates and lower crustal viscosities along the fault. The higher stress accumulations, earthquake recurrences, and elapsed times indicate higher seismic hazard on these two seismic gaps.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230615"},"PeriodicalIF":2.7,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989060","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":"An improved assessment of the geodetic/seismic deformation in the Southeastern Tibetan Plateau and its implications for regional seismic hazard","authors":"Zhengyang Pan ,&nbsp;Zhigang Shao ,&nbsp;Wuxing Wang ,&nbsp;Feng Long ,&nbsp;Zhenyu Wang ,&nbsp;Meixuan Hao","doi":"10.1016/j.tecto.2025.230623","DOIUrl":"10.1016/j.tecto.2025.230623","url":null,"abstract":"<div><div>To better understand the moment deficit and seismic coupling in the Southeastern Tibetan Plateau, we jointly analyzed the seismic catalogs and GNSS observations to improve the assessment of earthquake hazards in the area. This study involved an updated GNSS velocity field in a unified reference frame which is used to determine the strain field, and compiled several earthquake catalogs to estimate the Gutenberg-Richer parameter a-value and b-value, as well as the maximum earthquake magnitude in each seismic zone; in addition, the seismogenic thickness in the study region is also estimated. Through these products, we obtained the geodetic moment accumulation rate, seismic moment release rate, and the ratio between them. Our results show that the northern region - including the central-northern segment of the Xianshuihe fault, the Longmen Shan fault, and adjacent areas, and the southern region – including the Menglian fault, Nantinghe fault, and Lancangjiang fault, as well as neighboring regions, have higher seismic coupling indices (&gt;0.8), indicating that these areas may represent fully coupled seismic source zones, the future earthquake hazard in these areas may be lower compared to areas with low seismic coupling. In contrast, in the southern portion of the Xianshuihe fault, the Anninhe-Zemuhe fault, the Daliangshan fault, the southern part of the Jinshajiang fault, as well as the middle-northern part of the Red River fault and nearby regions, the seismic coupling is notably low (&lt;0.3), indicating significant seismic moment deficit and possibly considerable stress accumulation or long-term aseismic deformation in these areas. These areas have a moment deficit of 6.7–7.0 magnitude earthquakes or accumulating seismic moment energy equal to 0.4–1.0 missing earthquakes (M = 7). In addition, the XJF zone has deficit magnitudes ranging from 6.8 to 7.0 or 0.5–1.0 missing earthquakes (M = 7) during the longer catalog period. We classify these areas using a “red-yellow-gray” label system, designating areas with strong earthquake potential and high urgency as red, where future earthquake hazards should be noted. These findings are consistent with the earthquake hazard model, providing valuable insight into potential seismic activity. Taking into account the moment deficit and missing earthquakes estimated by the combination of the geodetic and seismology data, our approach can be applied to the seismic hazard assessment in the Tibetan Plateau or mainland China.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230623"},"PeriodicalIF":2.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989061","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":"Structural style of the Guañacos Fold and Thrust Belt (southern Central Andes): A tectonic setting for the Cura Mallín Basin revisited","authors":"Lucía Jagoe ,&nbsp;Martín Turienzo ,&nbsp;Lucía Sagripanti ,&nbsp;Natalia Sánchez ,&nbsp;Andrés Folguera","doi":"10.1016/j.tecto.2024.230611","DOIUrl":"10.1016/j.tecto.2024.230611","url":null,"abstract":"<div><div>The tectonic setting of the Oligo-Miocene Cura Mallín Basin in the southern Central Andes has been a topic of debate in recent years. Proposed models include extensional, compressional, and a hybrid-sequential model with an initial extension (∼20 Ma) followed by contraction (∼19 Ma). We conducted a detailed structural analysis to understand the tectonic evolution of the Cura Mallín Basin at the eastern Andean slope in the Guañacos Fold and Thrust Belt (FTB) (37°-38°S). This tectonic element provides exceptional exposure of the upper sedimentary infill of the Cura Mallín Basin. Despite detailed studies about composition, the structural configuration of this basin remains poorly understood. This study refines the age of the upper Cura Mallín Formation on the eastern Andean slope with a new detrital U/Pb date of 15.47 ± 0.28 Ma from the basal portion of the sedimentary sequence, indicating a maximum Middle Miocene deposition, in contrasts with the previous Oligo-Miocene age. This work presents the first balanced cross-sections for the Guañacos FTB. Structural analysis reveals a thin-skinned deformation style, contrasting with previous interpretations of thick-skinned deformation, with shortenings of 9.6 km (29 %) and 8.5 km (24 %). Therefore, significant Andean contraction at these latitudes was absorbed by the Guañacos FTB. Our model assumes that all deformation in the Cura Mallín Formation postdates deposition. Contractional deformation began on the Chilean Andean slope by ∼18.7 Ma, jumped to the Argentinean side at ∼12.5 Ma, and persisted beyond 6.5 Ma, with progressively diminishing intensity. Combined evidence from the Guañacos FTB and the eastern Chos Malal FTB, suggests synchronous deformation throughout the entire orogen during the Late Miocene. Additionally, these two belts record the reactivation of Miocene thrust faults during the Quaternary. This reactivation is potentially linked to the apparent persistence of the regional stress field since the Late Miocene.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230611"},"PeriodicalIF":2.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967739","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":"Subsurface structure of a foreland basin from analysis of gravity and aeromagnetic data: Revealing the basement structure of Gharb Basin, NW Morocco","authors":"Salma Zerouali Masror ,&nbsp;Ahmed Ntarmouchant ,&nbsp;Mustapha Elabouyi ,&nbsp;Telmo M. Bento dos Santos ,&nbsp;Ahmed Manar ,&nbsp;My Hachem Smaili ,&nbsp;Brahim Mali ,&nbsp;Nahla Ntarmouchant ,&nbsp;Badr El Mahrad ,&nbsp;Youssef Driouch ,&nbsp;Pedro Cachapuz ,&nbsp;Tiago Catita ,&nbsp;El Mehdi Jeddi","doi":"10.1016/j.tecto.2025.230622","DOIUrl":"10.1016/j.tecto.2025.230622","url":null,"abstract":"<div><div>Located in NW Morocco, Gharb Basin (GB) is a part of the foreland basin that was formed at the front of the Rif cordillera. It stands as a transition zone between the Maamora Plateau, to the South, and the Rif Belt, to the North. The first features of this basin began to appear in the Middle Miocene due to the compression caused by the convergence of Eurasia and Africa. The correlation of drilling data with gravity and aeromagnetic data, as well as the use of seismic data, has made it possible to reconstruct the architecture of this basin and to identify new structures responsible for the Neogene evolution of this region.</div><div>In this context, the analysis and interpretation of data extracted from this set of tools (drilling, gravity and aeromagnetic data) have allowed for the reconstruction of the subsurface geometry of this basin, to identify the lineaments traversing GB and to provide an overview of its tectonic framework. Some of these lineaments match previously mapped structures, whereas combination of seismic data for imaging existing structures and lineaments derived from gravimetry and aeromagnetism allowed to highlight new structures. The main identified structures include NW-SE oriented blind thrust fronts located beneath the nappe complex, associated with the advance of the Prerif Nappe towards the SW, as well as NE-SW oriented transpressive faults, interpreted as inherited faults from the Hercynian Orogeny and reactivated during the last Pliocene-Quaternary compressive phase. These structures formed NW-SE bulges and NE-SW oriented ridges that likely played a significant role in controlling sedimentation within this part of the foreland basin.</div><div>The results highlight the importance of combined geophysical methods for describing the macrostructure and architecture of GB, which is critical for hydrocarbon and water exploration.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230622"},"PeriodicalIF":2.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967740","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":"Surface deformation and geometry of the Himalayan frontal thrust system in Pakistan: An insight from InSAR and seismic interpretation","authors":"Kamil A. Qureshi PhD ,&nbsp;Shuhab D. Khan PhD ,&nbsp;Ozzy Tirmizi PhD ,&nbsp;Zaid Khan","doi":"10.1016/j.tecto.2024.230612","DOIUrl":"10.1016/j.tecto.2024.230612","url":null,"abstract":"<div><div>This research evaluated the current rate of surface deformation in the Western Himalayas, focusing on the western Salt Range and the Trans Indus Ranges. The study focused on identifying the presence of a ductile detachment and its correlation with seismic activity. We utilized the InSAR-SBAS (small baseline subset) method and 2D reflection seismic interpretation to analyze 2937 Sentinel-1 A interferograms collected from 2017 to 2023. The findings indicate that the western Salt Range, Kalabagh Fault, and Marwat-Khisor Ranges (Bannu Basin) are currently experiencing aseismic creep, with average surface deformation rates of 6 mm/year, 5.5 mm/year, and 7.6 mm/year, respectively. Interestingly, no surface deformation was observed in the Surghar Range front, although seismicity is mainly concentrated in the Kohat Fold-Thrust Belt. Despite experiencing a 5.2 Mw earthquake in 2018, the Kurram thrust does not show any surface deformation. The Global Navigation Satellite Systems (GNSS)-derived movement rates for the Salt Range and Kalabagh Fault align with the InSAR results. We also found that the presence of a single regional detachment (Precambrian Salt Range Formation) facilitates the aseismic movement of the Potwar and Bannu thrust sheet over the Punjab Foreland region, in contrast to the multiple detachments in the Kohat Fold-Thrust Belt.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230612"},"PeriodicalIF":2.7,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967738","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":"Identification of seismogenic fault network using earthquake focal mechanisms and stress constraints: A case of the 2016 Gyeongju earthquake sequence, South Korea","authors":"Chandong Chang ,&nbsp;Tae-Seob Kang ,&nbsp;Dabeen Heo","doi":"10.1016/j.tecto.2024.230613","DOIUrl":"10.1016/j.tecto.2024.230613","url":null,"abstract":"<div><div>We present a method to identify fault planes from earthquake focal mechanisms using stress field constraints to determine subsurface seismogenic fault geometry. Fault-plane ambiguity in focal mechanisms is resolved by applying two-step stress constraints. First, fault planes are inferred from the two nodal planes in each case by selecting those with the higher fault instability parameter, a function defined by plane orientations and stress state, using a commonly employed iterative linear stress inversion method. Second, the inferred fault planes are further screened by extracting those with a sufficiently high fault instability relative to the respective corresponding auxiliary planes, which is quantified by the instability ratio (<em>IR</em>) between the fault and auxiliary planes. Synthetic tests show that the threshold <em>IR</em> value, above which the inferred faults are all actual faults, varies with the degree of dispersion in fault instability. We apply the fault plane identification method to the 2016 Gyeongju earthquake sequence, which includes the largest instrumentally recorded event (M_L 5.8) on the Korean Peninsula. For the Gyeongju earthquake sequence, faults having <em>IR</em> values greater than either ∼1.2 or ∼1.3, depending on the variability in stress state, are considered actual faults. The orientations and locations of individual faults provide better constraints for modeling the fault network than using hypocentral locations only. The constructed fault network consists of several fault structures that display four distinct orientations and constitute two conjugate fault systems. Our method can contribute to fault modeling at depth by providing independent clues for seismogenic fault geometry.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230613"},"PeriodicalIF":2.7,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967774","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":"Reconciling high-resolution strain rate of continental China from GNSS data with the spherical spline interpolation","authors":"Zhengfeng Zhang ,&nbsp;Huai Zhang ,&nbsp;Yaolin Shi","doi":"10.1016/j.tecto.2024.230614","DOIUrl":"10.1016/j.tecto.2024.230614","url":null,"abstract":"<div><div>In this study, we propose a new generation of high-resolution strain rate models for present-day continental China. The models were developed using up-to-date Global Navigation Satellite System (GNSS) observation data from 3571 stations. A spherical spline method was used to reconcile the sparsely distributed GNSS velocity data into an integrated regional spherical coordinate frame. The model simultaneously calculates the strain rate with an ideal order of continuity while preserving the discontinuity between tectonically active major fault zones and deforming blocks. Inspection standards were used to assess the validity and resolution of the proposed model. The spherical spline method was deliberately examined and the fitting to the GNSS velocity data was justified to illustrate the inspection standards. A spherical harmonic model was also constructed for the resolution tests. By introducing test criteria, the spherical spline method can reproduce the velocity and strain-rate fields in substantial order, indicating that the developed method has a high level of applicability for estimating the strain rate in active tectonic regions and for global models. Finally, the spherical spline method was used with the GNSS velocity data to calculate the strain-rate fields in continental China. The correlation between the seismic mechanisms and the strain-rate field of earthquakes was also assessed. The results indicate that the proposed high-resolution strain rate model could be used to explain the deformation and evolution models of continental China.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"898 ","pages":"Article 230614"},"PeriodicalIF":2.7,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143140834","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":"Revisiting the dip-slip rate of the North Tehran Fault (Northern Iran) through studying the faulted materials and geomorphic markers","authors":"Maryam Heydari ,&nbsp;Mohammad R. Ghassemi","doi":"10.1016/j.tecto.2024.230610","DOIUrl":"10.1016/j.tecto.2024.230610","url":null,"abstract":"<div><div>The North Tehran Fault (NTF), located south of the Central Alborz Mountains, crosses north of the megacity of Tehran. The NTF is the principal active fault in Tehran, playing an essential role in the risk potential for the near ten million inhabitants of the capital city. Despite this risk, our knowledge about its slip rate is limited to two contradictory quantifications for the western segment of the fault. Slip rates remain unquantified towards the north and east, where it forms a transpressional duplex structure with the Mosha Fault. In this study, we combine detailed fieldwork on the previously documented outcrops of the NTF, including faulted colluvial and alluvial units in the west and uplifted remnants of the pediment surface in the east of the fault. We present new luminescence ages to temporally constrain the fault activity in the Middle-Late Pleistocene in selected sites. Our study in the western NTF reports a cumulative dip-slip rate of 0.56 ± 0.04 mm a⁻¹ for the Kan area and a minimum slip rate of 0.28 ± 0.02 mm a⁻¹ for the Hesarak area outcrops. On the hanging wall of the eastern NTF, a dated pediment surface has risen 579 m relative to the present base level of the Kond River in the footwall. Our analyses suggest that 299 m of such differential movement is thrust-related uplift, which indicates an uplift rate of 1.00 ± 0.12 mm a⁻¹. The dip-slip and shortening rates for the NTF at the Latyan Basin amounts to 1.39 ± 0.17 mm a⁻¹ and 0.97 ± 0.12 mm a⁻¹, respectively.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"897 ","pages":"Article 230610"},"PeriodicalIF":2.7,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143142244","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}