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Characteristics and origin of rift migration within the East China Sea Basin: Coupling relation with deep mantle dynamics
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105334
Yiming Liu , Fang Hao , Zhiping Wu , Lijun Liu , Qizhen Du
Tectonic migration is a significant geological phenomenon in rift basins, offering valuable insights into regional tectonic processes. This study comprehensively investigates the Cenozoic tectonic deformation, sedimentation, and magmatism of the East China Sea Basin. Through detailed analysis, we systematically outline the tectonic migration pattern and dynamic mechanism were systematically outlined, contributing novel and insightful findings to the field. Our results reveal that the basin experienced three episodic syn-rift stages during the Cenozoic, with the rift center migrated progressively oceanward. Differential deformation within the syn-depositional fault system caused spatial and temporal variations in the internal basin architecture. Based on these observation and numerical modeling results, we propose a new model to elucidate the mechanism of tectonic migration in back-arc rift basin. The initial rifting began in the West subbasins during the late Mesozoic and Paleocene, driven by the delamination-style removal of the younger Izanagi slab. During the Eocene, the second rifting episode migrated to the East subbasins, triggered by landward mantle wind and the resulting basal traction after detachment of the subduction of the former Izanagi slab. In contrast, the back-arc extension in the Okinawa Trough primarily resulted from slab rollback of the Philippine Sea Plate since the late Miocene. We emphasize that rifting mechanism within the basin varied significantly across time and space, reflecting the intricate interplay between plate dynamics and mantle processes. This refined understanding of the Cenozoic evolution of East Asia enhances our knowledge of crust-mantle interactions and provides deeper insights into lithosphere deformation.
{"title":"Characteristics and origin of rift migration within the East China Sea Basin: Coupling relation with deep mantle dynamics","authors":"Yiming Liu ,&nbsp;Fang Hao ,&nbsp;Zhiping Wu ,&nbsp;Lijun Liu ,&nbsp;Qizhen Du","doi":"10.1016/j.jsg.2024.105334","DOIUrl":"10.1016/j.jsg.2024.105334","url":null,"abstract":"<div><div>Tectonic migration is a significant geological phenomenon in rift basins, offering valuable insights into regional tectonic processes. This study comprehensively investigates the Cenozoic tectonic deformation, sedimentation, and magmatism of the East China Sea Basin. Through detailed analysis, we systematically outline the tectonic migration pattern and dynamic mechanism were systematically outlined, contributing novel and insightful findings to the field. Our results reveal that the basin experienced three episodic syn-rift stages during the Cenozoic, with the rift center migrated progressively oceanward. Differential deformation within the syn-depositional fault system caused spatial and temporal variations in the internal basin architecture. Based on these observation and numerical modeling results, we propose a new model to elucidate the mechanism of tectonic migration in back-arc rift basin. The initial rifting began in the West subbasins during the late Mesozoic and Paleocene, driven by the delamination-style removal of the younger Izanagi slab. During the Eocene, the second rifting episode migrated to the East subbasins, triggered by landward mantle wind and the resulting basal traction after detachment of the subduction of the former Izanagi slab. In contrast, the back-arc extension in the Okinawa Trough primarily resulted from slab rollback of the Philippine Sea Plate since the late Miocene. We emphasize that rifting mechanism within the basin varied significantly across time and space, reflecting the intricate interplay between plate dynamics and mantle processes. This refined understanding of the Cenozoic evolution of East Asia enhances our knowledge of crust-mantle interactions and provides deeper insights into lithosphere deformation.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105334"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
EBSD: Towards a better understanding of the role of deformation in the formation of schistose hypogene high-grade iron ore
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2025.105337
Carlos Alberto Rosière , Leonardo E. Lagoeiro , Flavia Cristina Silveira Braga , Ricardo Pagung
The Cuité iron ore deposit is located in the Guanhães tectonic block at the eastern margin of the São Francisco craton, and consists of schistose to massive lenses of high-grade ore (>50 wt% Fe) hosted in a tectonic sliver of iron formation and quartz mica schist of the Serra da Serpentina Group. The orebody is encased in a sheared domain of the Statherian Açucena granite of the Borrachudos Suite in association with quartz and pegmatite veins. The structure and mineralogy of the iron oxides distinguish four main textural types: a) the granular-textured hematite ore (GO), b) the schistose lamellar-granular or specularitic hematite ore (SO), c) the coarse-grained granular hematite ore (CGO) and (d) the massive magnetite ore (MO). The orebodies exhibit a ubiquitous continuous to domanial anastomosed schistosity defined by millimeter-sized elongated hematite plates (specularite), minor quartz, and shreds of kaolinite wrapping around granoblastic domains or laterally grading into coarse granular textured bodies. Magnetite occurs as single idioblastic grains or aggregates, usually oxidized to kenomagnetite/maghemite and martite, overgrowing the foliated fabric to form a massive textured ore. The sheared kaolinite is associated with the occurrence of anatectic pegmatite bodies and extensive hydrothermal alteration in the country rocks during the late collisional stages of the Brasiliano Orogeny which spanned from the Ediacaran to the early Cambrian periods. Textural EBSD (Electron Backscatter Diffraction) studies reveal a tectonic evolution during iron mineralization under ductile conditions, characterized by progressive (and overlapping) hematite crystal-plastic deformation, dynamic recrystallization, grain growth and the development of a typical CPO (crystallographic preferred orientations) pattern. The hematite [c]-axes form a maximum that coincides with the foliation pole extending along a girdle perpendicular to the stretching orientation. The textural modifications of the orebody developed during shearing and alteration by pegmatite fluids. The fingerprints of hydrothermal activity can be identified through the alteration of the country rocks, crystallization of minerals, and the mobilization of quartz by hot fluids, which is a major process of iron enrichment in shear zones.
The internal deformation of hematite contrasts with the observations of oriented strain-free fibrous specularite which is typically found precipitated in interstitial open spaces and strain shadow domains although in very small proportions in the Cuité deposit. This highlights the diversity of mechanisms involved in the formation of shear zone-hosted, schistose high-grade iron ore and brings new insights into its genetic interpretation.
{"title":"EBSD: Towards a better understanding of the role of deformation in the formation of schistose hypogene high-grade iron ore","authors":"Carlos Alberto Rosière ,&nbsp;Leonardo E. Lagoeiro ,&nbsp;Flavia Cristina Silveira Braga ,&nbsp;Ricardo Pagung","doi":"10.1016/j.jsg.2025.105337","DOIUrl":"10.1016/j.jsg.2025.105337","url":null,"abstract":"<div><div>The Cuité iron ore deposit is located in the Guanhães tectonic block at the eastern margin of the São Francisco craton, and consists of schistose to massive lenses of high-grade ore (&gt;50 wt% Fe) hosted in a tectonic sliver of iron formation and quartz mica schist of the Serra da Serpentina Group. The orebody is encased in a sheared domain of the Statherian Açucena granite of the Borrachudos Suite in association with quartz and pegmatite veins. The structure and mineralogy of the iron oxides distinguish four main textural types: a) the granular-textured hematite ore (GO), b) the schistose lamellar-granular or specularitic hematite ore (SO), c) the coarse-grained granular hematite ore (CGO) and (d) the massive magnetite ore (MO). The orebodies exhibit a ubiquitous continuous to domanial anastomosed schistosity defined by millimeter-sized elongated hematite plates (specularite), minor quartz, and shreds of kaolinite wrapping around granoblastic domains or laterally grading into coarse granular textured bodies. Magnetite occurs as single idioblastic grains or aggregates, usually oxidized to kenomagnetite/maghemite and martite, overgrowing the foliated fabric to form a massive textured ore. The sheared kaolinite is associated with the occurrence of anatectic pegmatite bodies and extensive hydrothermal alteration in the country rocks during the late collisional stages of the Brasiliano Orogeny which spanned from the Ediacaran to the early Cambrian periods. Textural EBSD (Electron Backscatter Diffraction) studies reveal a tectonic evolution during iron mineralization under ductile conditions, characterized by progressive (and overlapping) hematite crystal-plastic deformation, dynamic recrystallization, grain growth and the development of a typical CPO (crystallographic preferred orientations) pattern. The hematite [c]-axes form a maximum that coincides with the foliation pole extending along a girdle perpendicular to the stretching orientation. The textural modifications of the orebody developed during shearing and alteration by pegmatite fluids. The fingerprints of hydrothermal activity can be identified through the alteration of the country rocks, crystallization of minerals, and the mobilization of quartz by hot fluids, which is a major process of iron enrichment in shear zones.</div><div>The internal deformation of hematite contrasts with the observations of oriented strain-free fibrous specularite which is typically found precipitated in interstitial open spaces and strain shadow domains although in very small proportions in the Cuité deposit. This highlights the diversity of mechanisms involved in the formation of shear zone-hosted, schistose high-grade iron ore and brings new insights into its genetic interpretation.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105337"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Energy dissipation and fault dilation during intact-rock faulting
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105325
Ze'ev Reches , Nadav Wetzler
Rock-failure is usually analyzed by using the stress-based Coulomb criterion with the empirical parameters of cohesion and internal friction. We recently developed an alternative rock failure theory that is based on two conditions: rocks fail under a critical elastic energy threshold, and the applied elastic strain is accommodated by shear and dilation along the faults. We refer to this theory as Critical Energy Fault Failure (CEFF) and demonstrated its applicability to a range of rock failure experimental configurations from uniaxial to polyaxial loadings (Reches and Wetzler, 2022). In the present analysis, we utilized the energy-based CEFF theory to highlight further aspects of rock faulting: A. Evaluation of the dissipated energy associated with rock faulting which revealed that intact rock failure dissipates 35–55% of the available elastic energy. B. For a given normal stress, the CEFF calculated shear strength of a developing fault is smaller than the equivalent of the Coulomb shear strength. C. The predicted dilation associated with faulting of intact brittle rocks that is calculated by CEFF is supported by experimental observations. These three analyzed subjects provide important contributions for the understanding of rock failure processes.
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引用次数: 0
Long-lived seismic instability of a large intraplate brittle shear zone revealed by distributed slip zones and paleoseismic frictional melt, eastern Botswana
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105324
Debbie Mfa , Folarin Kolawole , Boniface Kgosidintsi , Rasheed Ajala , Elisha Shemang
In cratonic interiors, long-lived brittle shear zones host records of polyphase deformation, representing inherited structures that can host damaging earthquakes. Here, we explore the internal structure of the Kgomodikae Shear Zone (KSZ), signifying the western continuation of the ∼800-km long Precambrian Kgomodikae-Thabazimbi-Murchinson Fault System which extend along a region of widespread seismicity in southern Africa. At satellite-scale, the KSZ exhibits ENE-to-NE-striking subparallel zones of alternating high/low lineament clustering intensities, with peak-intensity zones that represent hydrologically-permeable principal brittle shear bands. In outcrops, we find pervasive occurrence of slip surfaces with dominant strike-slip paleo-slip vectors, and silica-cemented fault rocks hosting collocated quartz and pseudotachylyte vein clusters. Ground-based scanline fracture mapping reveals peak damage intensity in proximity of the satellite-mapped lineaments (localized high strain zones?), but with the pseudotachylytes occurring in both the peak- and flanking lower-intensity damage zones. The results suggest that the KSZ hosted paleoseismic ruptures that were not confined to its principal slip zones but may have nucleated on- or ruptured into off-fault splays; and that the NW-striking splays have greater reactivation tendency in contemporary stress field. In general, our findings highlight the nature of preexisting off-fault damage networks that accommodated earthquake rupture and propagation patterns in intraplate regions.
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引用次数: 0
Cretaceous to Paleogene polyphase faulting and paleostress inversions in the Taoshan-Zhuguangshan uranium metallogenic belt, South China Block
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2025.105340
Xianbing Xu , Shutao Chen , Meng Li , Lei Liu , Pulin Xu , Yuan Xia , Xiangsheng Tang
Polyphase faulting and fault reactivation are liable to occur in hydrothermal ore fields. However, the relationship between fault reactivation and mineralization remains ambiguous, particularly in the NE-SW-striking Taoshan-Zhuguangshan uranium metallogenic belt, South China Block. Field investigations, core observations, and paleostress inversions were carried out for the Lujing and Gulonggang hydrothermal ore fields. Field investigations and previous exploration profiles show that the main ore-controlling structures are the NE-SW-striking high-angle faults. The maximum density of poles shows that these faults dip mainly to SE at high angles (70–88°). Kinematic indicators and plunges of slickenlines indicate that these NE-SW-striking high-angle faults have undergone polyphase faulting and fault reactivation, including left-lateral strike-slip shearing, normal dip-slip motion, and right-lateral strike-slip shearing. Dip angles of faults (n = 667) and quartz veinlets (n = 407) in sub-vertical drill cores vary mainly from 30 to 65°and 60 to 70°for the Lujing ore field and from 20 to 50°and 25 to 85°for the Gulonggang ore field, respectively. The difference suggests that hydrothermal fluids migrated preferentially along the high-angle secondary fractures of the main faults. Paleostress inversions of fault-slip data (n = 375) revealed six stages of paleostress regimes, including 1) the early to middle Early Cretaceous extensional regime (subhorizontal NW-SE-trending σ3), 2) the late Early Cretaceous strike-slip regime (subhorizontal NNW-SSE-trending σ1), 3) the latest Early Cretaceous to early Late Cretaceous extensional regime (subhorizontal NW-SE-trending σ3), 4) the latest Cretaceous strike-slip regime (subhorizontal WNW-SEE-trending σ1), 5) the early Eocene strike-slip regime (subhorizontal NE-SW-trending σ1), and 6) the middle to late Eocene extensional regime (subhorizontal NE-SW-trending σ3). Field investigations, core observations, and previous metallogenic ages show that uranium mineralization in the Taoshan-Zhuguangshan uranium metallogenic belt occurred mainly along NE-SW-striking high-angle normal faults under the latest Early Cretaceous to early Late Cretaceous NW-SE extension. These high-angle normal faults were not new-born but reactivated from left-lateral strike-slip faults formed in the late Early Cretaceous strike-slip regime. NE-SW-striking polyphase faulting and fault reactivation during the Cretaceous were triggered by the subduction of the Paleo-Pacific Plate underneath the South China Block.
{"title":"Cretaceous to Paleogene polyphase faulting and paleostress inversions in the Taoshan-Zhuguangshan uranium metallogenic belt, South China Block","authors":"Xianbing Xu ,&nbsp;Shutao Chen ,&nbsp;Meng Li ,&nbsp;Lei Liu ,&nbsp;Pulin Xu ,&nbsp;Yuan Xia ,&nbsp;Xiangsheng Tang","doi":"10.1016/j.jsg.2025.105340","DOIUrl":"10.1016/j.jsg.2025.105340","url":null,"abstract":"<div><div>Polyphase faulting and fault reactivation are liable to occur in hydrothermal ore fields. However, the relationship between fault reactivation and mineralization remains ambiguous, particularly in the NE-SW-striking Taoshan-Zhuguangshan uranium metallogenic belt, South China Block. Field investigations, core observations, and paleostress inversions were carried out for the Lujing and Gulonggang hydrothermal ore fields. Field investigations and previous exploration profiles show that the main ore-controlling structures are the NE-SW-striking high-angle faults. The maximum density of poles shows that these faults dip mainly to SE at high angles (70–88°). Kinematic indicators and plunges of slickenlines indicate that these NE-SW-striking high-angle faults have undergone polyphase faulting and fault reactivation, including left-lateral strike-slip shearing, normal dip-slip motion, and right-lateral strike-slip shearing. Dip angles of faults (n = 667) and quartz veinlets (n = 407) in sub-vertical drill cores vary mainly from 30 to 65°and 60 to 70°for the Lujing ore field and from 20 to 50°and 25 to 85°for the Gulonggang ore field, respectively. The difference suggests that hydrothermal fluids migrated preferentially along the high-angle secondary fractures of the main faults. Paleostress inversions of fault-slip data (n = 375) revealed six stages of paleostress regimes, including 1) the early to middle Early Cretaceous extensional regime (subhorizontal NW-SE-trending σ<sub>3</sub>), 2) the late Early Cretaceous strike-slip regime (subhorizontal NNW-SSE-trending σ<sub>1</sub>), 3) the latest Early Cretaceous to early Late Cretaceous extensional regime (subhorizontal NW-SE-trending σ<sub>3</sub>), 4) the latest Cretaceous strike-slip regime (subhorizontal WNW-SEE-trending σ<sub>1</sub>), 5) the early Eocene strike-slip regime (subhorizontal NE-SW-trending σ<sub>1</sub>), and 6) the middle to late Eocene extensional regime (subhorizontal NE-SW-trending σ<sub>3</sub>). Field investigations, core observations, and previous metallogenic ages show that uranium mineralization in the Taoshan-Zhuguangshan uranium metallogenic belt occurred mainly along NE-SW-striking high-angle normal faults under the latest Early Cretaceous to early Late Cretaceous NW-SE extension. These high-angle normal faults were not new-born but reactivated from left-lateral strike-slip faults formed in the late Early Cretaceous strike-slip regime. NE-SW-striking polyphase faulting and fault reactivation during the Cretaceous were triggered by the subduction of the Paleo-Pacific Plate underneath the South China Block.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105340"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Morphotectonics, slope stability and paleostress studies from the Bhagirathi river section, western Himalaya (Uttarakhand, India)
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105288
Nikhil Puniya , Soumyajit Mukherjee , Atul Kumar Patidar , Mohit Kumar Puniya , Mery Biswas , Tuhin Biswas
We study parts of Tethyan, Higher and Lesser Himalayan rocks along the Bhagirathi river valley for morphotectonic analysis. The spatial and linear properties of the 21 sub-watersheds (S-WSs) and the Bhagirathi main watershed provide strong evidence of active tectonics mainly in the S-WS 3 (through which the South Tibetan Detachment passes), S-WS 9 (no fault runs), S-WS 12 (Vaikrita, Munsiari and Tons Thrusts cross) and S-WS 17 (Basul and Tons Thrusts occur). The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) has been used to classify the sub-watersheds as per the intensity of their recent tectonic activity. Seven morphometric parameters are used for the TOPSIS analysis. From the Lesser Himalayan section additionally, we perform landslide and paleostress studies. Eleven slopes cuts and 24 landslides were investigated to determine the mode of failure in a portion of the Rishikesh-Gangotri Highway. Landslides in soil strata is caused mainly by the low cohesion and due to the presence of coarse-grained loose materials. In the present study, most landslides (and earthquakes) have occurred in the vicinity of major thrusts. Where there is a high frequency of slickenside related to brittle normal faulting (K2 zone, near Dunda, Singuni and Dharasu Thrusts), a higher earthquake frequency of 3.5–5.2 magnitude is observed from the data set of around last 75 years. Paleostress analysis on data-sets of normal, reverse and strike-slip movements using the WinTensor software (ver. 5.8.8) yields NNE-SSW direction of extension for normal slip, NE-SW compression for reverse movement, and a pure strike-slip tensor with NNE-SSW shortening and WWN-SSE direction of maximum extension. The K2 zone where these deformations were most documented is also the place of slope instability and high present-day tectonic activity.
{"title":"Morphotectonics, slope stability and paleostress studies from the Bhagirathi river section, western Himalaya (Uttarakhand, India)","authors":"Nikhil Puniya ,&nbsp;Soumyajit Mukherjee ,&nbsp;Atul Kumar Patidar ,&nbsp;Mohit Kumar Puniya ,&nbsp;Mery Biswas ,&nbsp;Tuhin Biswas","doi":"10.1016/j.jsg.2024.105288","DOIUrl":"10.1016/j.jsg.2024.105288","url":null,"abstract":"<div><div>We study parts of Tethyan, Higher and Lesser Himalayan rocks along the Bhagirathi river valley for morphotectonic analysis. The spatial and linear properties of the 21 sub-watersheds (S-WSs) and the Bhagirathi main watershed provide strong evidence of active tectonics mainly in the S-WS 3 (through which the South Tibetan Detachment passes), S-WS 9 (no fault runs), S-WS 12 (Vaikrita, Munsiari and Tons Thrusts cross) and S-WS 17 (Basul and Tons Thrusts occur). The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) has been used to classify the sub-watersheds as per the intensity of their recent tectonic activity. Seven morphometric parameters are used for the TOPSIS analysis. From the Lesser Himalayan section additionally, we perform landslide and paleostress studies. Eleven slopes cuts and 24 landslides were investigated to determine the mode of failure in a portion of the Rishikesh-Gangotri Highway. Landslides in soil strata is caused mainly by the low cohesion and due to the presence of coarse-grained loose materials. In the present study, most landslides (and earthquakes) have occurred in the vicinity of major thrusts. Where there is a high frequency of slickenside related to brittle normal faulting (K2 zone, near Dunda, Singuni and Dharasu Thrusts), a higher earthquake frequency of 3.5–5.2 magnitude is observed from the data set of around last 75 years. Paleostress analysis on data-sets of normal, reverse and strike-slip movements using the WinTensor software (ver. 5.8.8) yields NNE-SSW direction of extension for normal slip, NE-SW compression for reverse movement, and a pure strike-slip tensor with NNE-SSW shortening and WWN-SSE direction of maximum extension. The K2 zone where these deformations were most documented is also the place of slope instability and high present-day tectonic activity.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105288"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143150913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An alternative formation mechanism for strike-slip fault in stable intracratonic basin
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105292
Lei Huang , Chiyang Liu , Zhao Wang , Yijun Zhou , Faqi He , Yongtao Liu , Yijian Huang
The cratonic strike-slip fault is a kind of fault developed by strike-slip motion in relatively stable tectonic settings. Compared to strike-slip faults developed in an active tectonic settings, cratonic strike-slip faults have small-scale characteristics, weak activity and are difficult to identify without high-quality 3D seismic data. To date, there have been few in-depth investigations of this kind of strike-slip fault, leading to a poor understanding of its characteristics and genetic mechanisms. In this study, we extensively investigated the cratonic strike-slip faults discovered in recent years in the Ordos Basins of China via 3D seismic data, and conducted comparative analyses with similar features observed in other intracratonic basins and active tectonic settings. This study suggests that cratonic strike-slip faults have some special characteristics, such as small displacement and low maturity even when they have been active during several orogenic processes, vertical stratified structural style, and decoupling with the basin periphery structures in terms of trending direction and kinematics. This paper proposed an alternative formation mechanism for cratonic strike-slip faults. The cratonic strike-slip faults nucleate from fractures induced by regional compressive stress instead of being directly inherited from preexisting faults or basement faults. These fractures experience brittle shearing movement under various structural processes, such as plane-differential compression, oblique compression, block rotation, and finally evolve into long strike-slip faults. The development of cratonic strike-slip faults probably record the special stress transmission within the stable craton, the weak in-plane tectonic stresses in the intracratonic basin, which mainly operate at shallow depths. This formation mechanism can provide a new perspective for the understanding of brittle deformation on the earth's surface, and help to elucidate the occurrence of earthquake activity in stable blocks.
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引用次数: 0
High-resolution geological studies of seismogenic structures
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105306
Zhikun Ren , Olaf Zielke , J. Bruce H. Shyu , Richard Walker
Strong earthquakes rank among the most devastating natural disasters, with the potential to inflict catastrophic damage on communities and critical infrastructure worldwide. The structural geological and geophysical study of seismogenic features remains a cornerstone of earthquake research, providing essential insights into the dynamic processes driving these powerful events. High-resolution investigations in geomorphology, stratigraphy, and structural geology allow for a detailed understanding of the spatial and temporal characteristics of seismic deformations, encompassing co-seismic, post-seismic, and inter-seismic stages, potentially spanning multiple earthquake cycles. The integration of cutting-edge techniques—such as high-resolution data from Light Detection and Ranging (LiDAR), Structure from Motion (SfM), geophysical surveys, drilling, and frictional laboratory experiments—coupled with precise dating methods, enables quantitative analysis at high spatial resolutions across diverse temporal ranges, from years to millions of years. Recent advancements in frictional experimental techniques and numerical modeling have also significantly refined our understanding of deformation processes within seismogenic structures. This special issue compiles research on tectonic activities related to seismogenic structures from varied global tectonic setting, with a focus on leveraging high-resolution spatial data and sophisticated dating techniques. The contributions aim to deepen our understanding of the dynamics underlying strong earthquakes and improve our capacity for seismic hazard assessment.
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引用次数: 0
Microstructures along volcanic avalanche fault zone in French Massif Central
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105327
Karine Bernard
Microscale structures are rarely studied along volcanic avalanche fault zones. Here, the well-exposed basal contacts of the Perrier avalanche units are described in the French Massif Central, which exhibit various deformed sedimentary structures, including planar sheared contacts, asymmetric undulations, schistose bands within a sandy matrix, sigmoids, shears bounding subangular clasts, and cataclastic shear bands.
The occurrence of a breaking force chain along clastic veins, antithetic rotational shear, and clastic disaggregation characterize sequential microfabrics. The quartz microstructures observed along the basement of the volcanic avalanche units indicate a combination of syn and post-seismic creep in the low temperature plasticity regime. The microstructural evolution of mica fish records deformation accommodated at variable pressure and thermal conditions along clastic shear bands. Granular segregations with interclastic pumice matrices and cataclastic matrix transformations are related to co-seismic fluids. This volcanic avalanche fault zone has experienced a vertical and lateral gradient of sequential deformations related to lateral spreading in a rift zone that contained a topographic obstacle.
{"title":"Microstructures along volcanic avalanche fault zone in French Massif Central","authors":"Karine Bernard","doi":"10.1016/j.jsg.2024.105327","DOIUrl":"10.1016/j.jsg.2024.105327","url":null,"abstract":"<div><div>Microscale structures are rarely studied along volcanic avalanche fault zones. Here, the well-exposed basal contacts of the Perrier avalanche units are described in the French Massif Central, which exhibit various deformed sedimentary structures, including planar sheared contacts, asymmetric undulations, schistose bands within a sandy matrix, sigmoids, shears bounding subangular clasts, and cataclastic shear bands.</div><div>The occurrence of a breaking force chain along clastic veins, antithetic rotational shear, and clastic disaggregation characterize sequential microfabrics. The quartz microstructures observed along the basement of the volcanic avalanche units indicate a combination of syn and post-seismic creep in the low temperature plasticity regime. The microstructural evolution of mica fish records deformation accommodated at variable pressure and thermal conditions along clastic shear bands. Granular segregations with interclastic pumice matrices and cataclastic matrix transformations are related to co-seismic fluids. This volcanic avalanche fault zone has experienced a vertical and lateral gradient of sequential deformations related to lateral spreading in a rift zone that contained a topographic obstacle.</div></div>","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105327"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143150880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Erratum to “Did along-strike changes in continental subduction styles occur in the Dabie-Sulu orogenic belt?” [Journal of Structural Geology 191 (2025) 105321]
IF 2.6 2区 地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY Pub Date : 2025-02-01 DOI: 10.1016/j.jsg.2024.105335
Ruirui Wang , Zhong-Hai Li , Qihua Cui , Zhiqin Xu
{"title":"Erratum to “Did along-strike changes in continental subduction styles occur in the Dabie-Sulu orogenic belt?” [Journal of Structural Geology 191 (2025) 105321]","authors":"Ruirui Wang ,&nbsp;Zhong-Hai Li ,&nbsp;Qihua Cui ,&nbsp;Zhiqin Xu","doi":"10.1016/j.jsg.2024.105335","DOIUrl":"10.1016/j.jsg.2024.105335","url":null,"abstract":"","PeriodicalId":50035,"journal":{"name":"Journal of Structural Geology","volume":"191 ","pages":"Article 105335"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Journal of Structural Geology
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