In this paper, remote sensing techniques,as well as field studies, have been used to investigate the geomorphological processes and landscape evolution along the Saravan Fault, SE Iran to highlight how topographic fea...In this paper, remote sensing techniques,as well as field studies, have been used to investigate the geomorphological processes and landscape evolution along the Saravan Fault, SE Iran to highlight how topographic features were influenced by active tectonics. Quantitative geomorphic analysis was carried out using mountain-front sinuosity(Smf),valley floor width-valley height ratio(Vf), drainage basin asymmetry factor(Af), Hypsometric integral(Hi), drainage basin shape index(Bs), mean axial slope of channel(MASC), standard deviation of topography(STD) and index of active tectonic(Iat).Remote sensing techniques, as well as field studies revealed that the Saravan Fault have three parts trending N-S, NW-SE, and E-W. Obtained results show that basins with high Iat index are located at where the strike of the Saravan Faults changes and where several strike-slip faults are crossed the Saravan fault.展开更多
Anhua-Xupu fault belt plays a very important role in the formation of Xuefeng Mountains. The fault belt shows an arc-structure extruding towards NW. Fault rocks, microstructures and homogeneous temperature (concentrat...Anhua-Xupu fault belt plays a very important role in the formation of Xuefeng Mountains. The fault belt shows an arc-structure extruding towards NW. Fault rocks, microstructures and homogeneous temperature (concentrated around 160℃) of fluid inclusions in the quartz veins shows that the fault belt mainly underwent shallow brittle deformation and the highest-grade dynamic metamorphic rock is mylonitized sericite phyllite. The ESR (Electron Spin Resonance) dating from the quartz veins in the fault rocks shows that the fault belt underwent two intense fluid movement stages at Yanshanian (156.9~136.2Ma, 119.8~90.6Ma); moreover not only the occurrence and microstructures but also the homogeneous temperature of the quartz veins developed in that two stages show obvious diversity, which can prove that there exists the reversion period of Mesozoic extension and compression movement of Xuefeng mountains between these two stages .展开更多
As the main part of the “central mountain system” in the continent of China, the Qinling, Qilian and Kunlun orogenic belts have been comprehensively and deeply studied since the 1970s and rich fruits have been reape...As the main part of the “central mountain system” in the continent of China, the Qinling, Qilian and Kunlun orogenic belts have been comprehensively and deeply studied since the 1970s and rich fruits have been reaped. However, these achievements were mostly confined to an individual orogenic belt and the study of the mutual relationship among the three orogenic belts was obliged to depend on comparative studies. Different views were produced therefrom. The material composition and structural features of the junction region show that there are several epicontinental and intracontinental transform faults developed in different periods. Restricted by these transform faults, the large-scale lateral movements and, as a consequence, complicated magmatism and tectonic deformation took place in the orogenic belts. According to these features, the authors put forward a three-stage junction and evolution model and point out that there is not a single junction zone traversing from west to east but that the three orogenic belts have been joined progressively by the epicontinental and intracontinental transform faults.展开更多
The basin-range coupling relation is a leading subject of the modern geology. In geometry, relations of this type include couplings between stretched orogenic belt and down-faulted basin, compressional orogenic belt a...The basin-range coupling relation is a leading subject of the modern geology. In geometry, relations of this type include couplings between stretched orogenic belt and down-faulted basin, compressional orogenic belt and foreland basin, strike-slip orogenic belt and strike-slip basin and so on. Fault chains are the key for these couplings and there are typical examples for all these cases. The North China down-faulted basin is coupled west with the Taihang uplift, east with the Jiao-Liao Mountains, north with the Yanshan orogenic belt and south with the Dabie orogenic belt, that is to say, the central down-faulted basin and the surrounding orogenic belts bear a coupling relation within a uniform dynamistic system. Study shows that the central down-faulted basin and the North China mantle sub-plume structure have a close relation during their formation. Owing to intensive mantle sub-plume uplifting, the bottom of the lithosphere suffered from resistance, which caused the lithosphere of the eastern North China to be heated, thinned and fault-depressed. Meanwhile, mantle rocks that were detached outwards in the shape of mushroom was dissected by surrounding ductile shearing zones, which lead to decompression and unloading to generate hypomagmas, and a series of mantle-branch structures were formed around the down-faulted basin. There is an obvious comparability among these mantle branch structures (orogenic belts), and they have basin-range coupling relations with the central down-faulted basins.展开更多
The Longmen Mountains and adjacent regions on the eastern margin of the Tibetan plateau can be divided into three tectonic units: the eastern Songpan—Garzê fold belt, the Longmen Mountains (Longmen Shan) Thrust...The Longmen Mountains and adjacent regions on the eastern margin of the Tibetan plateau can be divided into three tectonic units: the eastern Songpan—Garzê fold belt, the Longmen Mountains (Longmen Shan) Thrust—Nappe belt and the Western Sichuan foreland basin that occupies the western part of the Sichuan basin. The Longmen Shan Thrust—Nappe belt is subdivided by six northwest\|dipping major listric thrusts, with accompanying duplexes and imbricate fans, into five large\|scale nappes (Chen & Wilson, 1996). In the inner Longmen Shan, the nappe units have incorporated both Mesoproterozoic basement and Sinian (Neoproterozoic) to Triassic cover sequences as “thick\|skinned" horses. Whereas, in the frontal Longmen Shan, Sinian to Cretaceous cover sediments have been stripped from the basement as “thin\|skinned" fold and thrust sheets, including extensively distributed klippen structures. Pre\|thrusting extension during Devonian to middle Late Triassic times resulted in syndepositional normal faults. Structural inversion of these faults initiated the “Peng Xian—Guan Xian basement complex", Jiuding Shan and Tangwangzhai nappes, during an early episode of the Indosinian Orogeny (Norian to Rhaetian). This was followed by episodic thrusting during latest Triassic to Early Cretaceous times to develop the Guan Xian—An Xian and Southeastern Marginal nappes that have incorporated sediments from the neighbouring foreland basin into the frontal part of the Thrust—Nappe belt. Differential thrusting occurred across the Thrust—Nappe belt during a Late Miocene reactivation of the pre\|existing faults.展开更多
Through field geological survey, the authors found that abundant thrust faults developed in the Longmen （龙门） Mountain thrust belt. These faults can be divided into thrust faults and strike-slip faults according to...Through field geological survey, the authors found that abundant thrust faults developed in the Longmen （龙门） Mountain thrust belt. These faults can be divided into thrust faults and strike-slip faults according to their formation mechanisms and characteristics. Furthermore, these faults can be graded into primary fault, secondary fault, third-level fault, and fourth-level fault according to their scale and role in the tectonic evolution of Longmen Mountain thrust belt. Each thrustfault is such as composed of several secondary faults, Qingchuan （青川）-Maowen （茂汶） fault zone is composed of Qiaozhuang （乔庄） fault, Qingxi （青溪） fault, Maowen fault, Ganyanggou （赶羊沟） fault, etc.. The Longmen Mountain thrust belt experienced early Indosinian movement, Anxian （安县） movement, Yanshan （燕山） movement, and Himalayan movement, and the faults formed gradually from north to south.展开更多
以老湾金矿带上上河-彭家老庄、老湾-盛老庄金矿床为研究对象，通过野外地表和坑道观察，进行断裂产状统计、配套分析及构造性质与矿化类型耦合关系的研究，确立了老湾金矿带控矿构造体系性质及组合型式。上上河-彭家老庄金矿床以石英...以老湾金矿带上上河-彭家老庄、老湾-盛老庄金矿床为研究对象，通过野外地表和坑道观察，进行断裂产状统计、配套分析及构造性质与矿化类型耦合关系的研究，确立了老湾金矿带控矿构造体系性质及组合型式。上上河-彭家老庄金矿床以石英脉型矿化较为发育为特点，控矿断裂属走滑构造体系中的R型张扭性裂隙带，向北陡倾，走向（290°～310°）与主剪切带方向（286°）交角约为15°，具右行剪切特征，滑距约10 m。老湾-盛老庄矿床以蚀变岩型矿化为特征，充填脉型矿化不发育，其金矿控矿断裂属 P 型压扭性裂隙，向南缓倾，其总体走向近东西（约92°），与主剪切带方向的另一端交角约15°。3条规模较大的断裂蚀变带平面上右型侧列特点反映其滑移方向与上上河-彭家老庄控矿断裂滑移方向一致。综合整个矿带断裂产状及矿化信息，认为老湾金矿带控矿构造总体为以老湾和松扒断裂为边界断裂，由里德尔剪切体系中的P型和R型剪切带连结形成的辫状右行走滑剪切带。结合桐柏造山带区域地质演化历史，分析认为该脆性断裂构造带是早期韧性剪切带继承性演化的结果，反映桐柏造山带不同构造块体间斜向碰撞及随后地壳抬升作用的动力学演化过程。老湾金矿带右行走滑构造体系与成矿作用的耦合关系对矿床成因提供重要地质约束。展开更多
基金the Research Council of University of Sistan and Baluchestan which has supported the project
文摘In this paper, remote sensing techniques,as well as field studies, have been used to investigate the geomorphological processes and landscape evolution along the Saravan Fault, SE Iran to highlight how topographic features were influenced by active tectonics. Quantitative geomorphic analysis was carried out using mountain-front sinuosity(Smf),valley floor width-valley height ratio(Vf), drainage basin asymmetry factor(Af), Hypsometric integral(Hi), drainage basin shape index(Bs), mean axial slope of channel(MASC), standard deviation of topography(STD) and index of active tectonic(Iat).Remote sensing techniques, as well as field studies revealed that the Saravan Fault have three parts trending N-S, NW-SE, and E-W. Obtained results show that basins with high Iat index are located at where the strike of the Saravan Faults changes and where several strike-slip faults are crossed the Saravan fault.
基金This study was financially supported by China National Science Foundation Grant No.40334037SINOPEC key project.
文摘Anhua-Xupu fault belt plays a very important role in the formation of Xuefeng Mountains. The fault belt shows an arc-structure extruding towards NW. Fault rocks, microstructures and homogeneous temperature (concentrated around 160℃) of fluid inclusions in the quartz veins shows that the fault belt mainly underwent shallow brittle deformation and the highest-grade dynamic metamorphic rock is mylonitized sericite phyllite. The ESR (Electron Spin Resonance) dating from the quartz veins in the fault rocks shows that the fault belt underwent two intense fluid movement stages at Yanshanian (156.9~136.2Ma, 119.8~90.6Ma); moreover not only the occurrence and microstructures but also the homogeneous temperature of the quartz veins developed in that two stages show obvious diversity, which can prove that there exists the reversion period of Mesozoic extension and compression movement of Xuefeng mountains between these two stages .
文摘As the main part of the “central mountain system” in the continent of China, the Qinling, Qilian and Kunlun orogenic belts have been comprehensively and deeply studied since the 1970s and rich fruits have been reaped. However, these achievements were mostly confined to an individual orogenic belt and the study of the mutual relationship among the three orogenic belts was obliged to depend on comparative studies. Different views were produced therefrom. The material composition and structural features of the junction region show that there are several epicontinental and intracontinental transform faults developed in different periods. Restricted by these transform faults, the large-scale lateral movements and, as a consequence, complicated magmatism and tectonic deformation took place in the orogenic belts. According to these features, the authors put forward a three-stage junction and evolution model and point out that there is not a single junction zone traversing from west to east but that the three orogenic belts have been joined progressively by the epicontinental and intracontinental transform faults.
基金supported by the National Natural Science Foundation of China(grants 40272088,40072073)the Knowledge Innovation Project of the Chinese Academy of Sciences(KZCX1-07)the Project of Large scale Geological Survey in China(200110200038).
文摘The basin-range coupling relation is a leading subject of the modern geology. In geometry, relations of this type include couplings between stretched orogenic belt and down-faulted basin, compressional orogenic belt and foreland basin, strike-slip orogenic belt and strike-slip basin and so on. Fault chains are the key for these couplings and there are typical examples for all these cases. The North China down-faulted basin is coupled west with the Taihang uplift, east with the Jiao-Liao Mountains, north with the Yanshan orogenic belt and south with the Dabie orogenic belt, that is to say, the central down-faulted basin and the surrounding orogenic belts bear a coupling relation within a uniform dynamistic system. Study shows that the central down-faulted basin and the North China mantle sub-plume structure have a close relation during their formation. Owing to intensive mantle sub-plume uplifting, the bottom of the lithosphere suffered from resistance, which caused the lithosphere of the eastern North China to be heated, thinned and fault-depressed. Meanwhile, mantle rocks that were detached outwards in the shape of mushroom was dissected by surrounding ductile shearing zones, which lead to decompression and unloading to generate hypomagmas, and a series of mantle-branch structures were formed around the down-faulted basin. There is an obvious comparability among these mantle branch structures (orogenic belts), and they have basin-range coupling relations with the central down-faulted basins.
文摘The Longmen Mountains and adjacent regions on the eastern margin of the Tibetan plateau can be divided into three tectonic units: the eastern Songpan—Garzê fold belt, the Longmen Mountains (Longmen Shan) Thrust—Nappe belt and the Western Sichuan foreland basin that occupies the western part of the Sichuan basin. The Longmen Shan Thrust—Nappe belt is subdivided by six northwest\|dipping major listric thrusts, with accompanying duplexes and imbricate fans, into five large\|scale nappes (Chen & Wilson, 1996). In the inner Longmen Shan, the nappe units have incorporated both Mesoproterozoic basement and Sinian (Neoproterozoic) to Triassic cover sequences as “thick\|skinned" horses. Whereas, in the frontal Longmen Shan, Sinian to Cretaceous cover sediments have been stripped from the basement as “thin\|skinned" fold and thrust sheets, including extensively distributed klippen structures. Pre\|thrusting extension during Devonian to middle Late Triassic times resulted in syndepositional normal faults. Structural inversion of these faults initiated the “Peng Xian—Guan Xian basement complex", Jiuding Shan and Tangwangzhai nappes, during an early episode of the Indosinian Orogeny (Norian to Rhaetian). This was followed by episodic thrusting during latest Triassic to Early Cretaceous times to develop the Guan Xian—An Xian and Southeastern Marginal nappes that have incorporated sediments from the neighbouring foreland basin into the frontal part of the Thrust—Nappe belt. Differential thrusting occurred across the Thrust—Nappe belt during a Late Miocene reactivation of the pre\|existing faults.
基金supported by the National Natural Science Foundation of China (Nos. 40672143, 40472107, 40172076)the National Basic Research Program of China (Nos. 2005CB422107, G1999043305)+1 种基金Development Foundation of Key Laboratory for Hydrocarbon Accumulation of the Ministry of Education of China (No. 2003-03)Project of the South-west Petroleum Natural Gas Subcompany of SINOPEC (No. GJ-51-0602)
文摘Through field geological survey, the authors found that abundant thrust faults developed in the Longmen （龙门） Mountain thrust belt. These faults can be divided into thrust faults and strike-slip faults according to their formation mechanisms and characteristics. Furthermore, these faults can be graded into primary fault, secondary fault, third-level fault, and fourth-level fault according to their scale and role in the tectonic evolution of Longmen Mountain thrust belt. Each thrustfault is such as composed of several secondary faults, Qingchuan （青川）-Maowen （茂汶） fault zone is composed of Qiaozhuang （乔庄） fault, Qingxi （青溪） fault, Maowen fault, Ganyanggou （赶羊沟） fault, etc.. The Longmen Mountain thrust belt experienced early Indosinian movement, Anxian （安县） movement, Yanshan （燕山） movement, and Himalayan movement, and the faults formed gradually from north to south.
文摘以老湾金矿带上上河-彭家老庄、老湾-盛老庄金矿床为研究对象，通过野外地表和坑道观察，进行断裂产状统计、配套分析及构造性质与矿化类型耦合关系的研究，确立了老湾金矿带控矿构造体系性质及组合型式。上上河-彭家老庄金矿床以石英脉型矿化较为发育为特点，控矿断裂属走滑构造体系中的R型张扭性裂隙带，向北陡倾，走向（290°～310°）与主剪切带方向（286°）交角约为15°，具右行剪切特征，滑距约10 m。老湾-盛老庄矿床以蚀变岩型矿化为特征，充填脉型矿化不发育，其金矿控矿断裂属 P 型压扭性裂隙，向南缓倾，其总体走向近东西（约92°），与主剪切带方向的另一端交角约15°。3条规模较大的断裂蚀变带平面上右型侧列特点反映其滑移方向与上上河-彭家老庄控矿断裂滑移方向一致。综合整个矿带断裂产状及矿化信息，认为老湾金矿带控矿构造总体为以老湾和松扒断裂为边界断裂，由里德尔剪切体系中的P型和R型剪切带连结形成的辫状右行走滑剪切带。结合桐柏造山带区域地质演化历史，分析认为该脆性断裂构造带是早期韧性剪切带继承性演化的结果，反映桐柏造山带不同构造块体间斜向碰撞及随后地壳抬升作用的动力学演化过程。老湾金矿带右行走滑构造体系与成矿作用的耦合关系对矿床成因提供重要地质约束。
