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Analysis of faulting destruction and water supply pipeline damage from the first mainshock of the February 6,2023 Türkiye earthquake doublet
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作者 Xiaoqing Fan Libao Zhang +2 位作者 Juke Wang Yefei Ren Aiwen Liu 《Earthquake Science》 2024年第1期78-90,共13页
In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highw... In 2023,two consecutive earthquakes exceeding a magnitude of 7 occurred in Türkiye,causing severe casualties and economic losses.The damage to critical urban infrastructure and building structures,including highways,railroads,and water supply pipelines,was particularly severe in areas where these structures intersected the seismogenic fault.Critical infrastructure projects that traverse active faults are susceptible to the influence of fault movement,pulse velocity,and ground motions.In this study,we used a unique approach to analyze the acceleration records obtained from the seismic station array(9 strong ground motion stations)located along the East Anatolian Fault(the seismogenic fault of the MW7.8 mainshock of the 2023 Türkiye earthquake doublet).The acceleration records were filtered and integrated to obtain the velocity and displacement time histories.We used the results of an on-site investigation,jointly conducted by China Earthquake Administration and Türkiye’s AFAD,to analyze the distribution of PGA,PGV,and PGD recorded by the strong motion array of the East Anatolian Fault.We found that the maximum horizontal PGA in this earthquake was 3.0 g,and the maximum co-seismic surface displacement caused by the East Anatolian Fault rupture was 6.50 m.As the fault rupture propagated southwest,the velocity pulse caused by the directional effect of the rupture increased gradually,with the maximum PGA reaching 162.3 cm/s.We also discussed the seismic safety of critical infrastructure projects traversing active faults,using two case studies of water supply pipelines in Türkiye that were damaged by earthquakes.We used a three-dimensional finite element model of the PE(polyethylene)water pipeline at the Islahiye State Hospital and fault displacement observations obtained through on-site investigation to analyze pipeline failure mechanisms.We further investigated the effect of the fault-crossing angle on seismic safety of a pipeline,based on our analysis and the failure performance of the large-diameter Thames Water pipeline during the 1999 Kocaeli earthquake.The seismic method of buried pipelines crossing the fault was summarized. 展开更多
关键词 Türkiye earthquake fault displacement near-fault ground motion velocity pulse water supply pipeline
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Active Faulting Pattern,Present-day Tectonic Stress Field and Block Kinematics in the East Tibetan Plateau 被引量:34
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作者 ZHANG Yueqiao DONG Shuwen YANG Nong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第4期694-712,共19页
This paper examines major active faults and the present-day tectonic stress field in the East Tibetan Plateau by integrating available data from published literature and proposes a block kinematics model of the region... This paper examines major active faults and the present-day tectonic stress field in the East Tibetan Plateau by integrating available data from published literature and proposes a block kinematics model of the region. It shows that the East Tibetan Plateau is dominated by strike-slip and reverse faulting stress regimes and that the maximum horizontal stress is roughly consistent with the contemporary velocity field, except for the west Qinling range where it parallels the striking of the major strike-slip faults. Active tectonics in the East Tibetan Plateau is characterized by three faulting systems. The left-slip Kunlun-Qinling faulting system combines the east Kunlun fault zone, sinistral oblique reverse faults along the Minshan range and two major NEE-striking faults cutting the west Qinling range, which accommodates eastward motion, at 10--14 mm/a, of the Chuan-Qing block. The left-slip Xianshuihe faulting system accommodated clockwise rotation of the Chuan-Dian block. The Longmenshan thrust faulting system forms the eastern margin of the East Tibetan Plateau and has been propagated to the SW of the Sichuan basin. Crustal shortening across the Longmenshan range seems low (2-4 mm/a) and absorbed only a small part of the eastward motion of the Chuan-Qing block. Most of this eastward motion has been transmitted to South China, which is moving SEE-ward at 7-9 mm/a. It is suggested from geophysical data interpretation that the crust and lithosphere of the East Tibetan Plateau is considerably thickened and theologically layered. The upper crust seems to be decoupled from the lower crust through a decollement zone at a depth of 15-20 kin, which involved the Longmenshan fault belt and propagated eastward to the SW of the Sichuan basin. The Wenchuan earthquake was just formed at the bifurcated point of this decollement system. A rheological boundary should exist beneath the Longmenshan fault belt where the lower crust of the East Tibetan Plateau and the lithospheric mantle of the Yangze block are juxtaposed. 展开更多
关键词 Longmenshan fault belt active faulting pattern active tectonic stress field extrusion tectonics Wenchuan earthquake East Tibetan Plateau
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Assessing current faulting behaviors and seismic risk of the Anninghe-Zemuhe fault zone from seismicity parameters 被引量:19
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作者 易桂喜 闻学泽 +1 位作者 范军 王思维 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期322-333,共12页
Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for pot... Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for potential large earthquakes. The authors map the probable asperities from the abnormally low b-value distribution, develop and employ a method for identifying current faulting behaviors of individual fault segment from the combinations of multiple seismicity parameter values, and make an effort to estimate the average recurrence intervals of character-istic earthquakes by using the parameters of magnitude-frequency relationship of the asperity segment. The result suggests that the studied fault zone contains 5 segments of different current faulting behaviors. Among them, the Mianning-Xichang segment of the Anninghe fault has been locked under high stress, its central part is probably an asperity with a relatively large scale. The Xichang-Puge segment of the Zemuhe fault displays very low seismicity under low stress. Both the locked segment and the low-seismicity segment can be outlined on the across-profile of relocated hypocenter depths. The Mianning-Xichang segment is identified to be the one with potential large earth-quake risk, for which the average recurrence interval between the latest M = 6.7 earthquake in 1952 and the next characteristic event is estimated to be 55 to 67 years, and the magnitude of the potential earthquake between 7.0 and 7.5. Also, it has been preliminarily suggested that for a certain fault segment, its faulting behaviors may change and evolve with time gradually. 展开更多
关键词 seismicity parameter faulting behavior ASPERITY potential seismic risk Anninghe-Zemuhe fault zone
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Centrifuge modeling of buried continuous pipelines subjected to normal faulting 被引量:11
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作者 Majid Moradi Mahdi Rojhani +1 位作者 Abbas Galandarzadeh Shiro Takada 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期155-164,共10页
Seismic ground faulting is the greatest hazard for continuous buried pipelines.Over the years,researchers have attempted to understand pipeline behavior mostly via numerical modeling such as the finite element method.... Seismic ground faulting is the greatest hazard for continuous buried pipelines.Over the years,researchers have attempted to understand pipeline behavior mostly via numerical modeling such as the finite element method.The lack of well-documented field case histories of pipeline failure from seismic ground faulting and the cost and complicated facilities needed for full-scale experimental simulation mean that a centrifuge-based method to determine the behavior of pipelines subjected to faulting is best to verify numerical approaches.This paper presents results from three centrifuge tests designed to investigate continuous buried steel pipeline behavior subjected to normal faulting.The experimental setup and procedure are described and the recorded axial and bending strains induced in a pipeline are presented and compared to those obtained via analytical methods.The influence of factors such as faulting offset,burial depth and pipe diameter on the axial and bending strains of pipes and on ground soil failure and pipeline deformation patterns are also investigated.Finally,the tensile rupture of a pipeline due to normal faulting is investigated. 展开更多
关键词 centrifuge models buried pipeline normal faulting EARTHQUAKE permanent ground deformation
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Neotectonics of the Eastern Margin of the Tibetan Plateau: New Geological Evidence for the Change from Early Pleistocene Transpression to Late Pleistocene-Holocene Strike-slip Faulting 被引量:6
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作者 ZHANG Yueqiao LI Hailong LI Jian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期467-485,共19页
We present in this paper some new evidence for the change during the Quaternary in kinematics of faults cutting the eastern margin of the Tibetan Plateau. It shows that significant shortening deformation occurred duri... We present in this paper some new evidence for the change during the Quaternary in kinematics of faults cutting the eastern margin of the Tibetan Plateau. It shows that significant shortening deformation occurred during the Early Pleistocene, evidenced by eastward thrusting of Mesozoic carbonates on the Pliocene lacustrine deposits along the Minjiang upstream fault zone and by development of the transpressional ridges of basement rocks along the Anninghe river valley. The Middle Pleistocene seems to be a relaxant stage with local development of the intra-mountain basins particularly prominent along the Minjiang Upstream and along the southern segment of the Anninghe River Valley. This relaxation may have been duo to a local collapse of the thickened crust attained during the late Neogene to early Pleistocene across this marginal zone. Fault kinematics has been changed since the late Pleistocene, and was predominated by reverse sinistral strike-slip along the Minshan Uplift, reverse dextral strike-slip on the Longmenshan fault zone and pure sinistral strike-slip on the Anninghe fault. This change in fault kinematics during the Quaternary allows a better understanding of the mechanism by which the marginal ranges of the plateau has been built through episodic activities. 展开更多
关键词 Quaternary transpression strike-slip faulting eastern margin of the Tibetan Plateau Minjiang upstream fault back Longmenshan fault Anninghe faulted valley
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Normal Faulting Type Earthquake Activities in the Tibetan Plateau and Its Tectonic Implication 被引量:3
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作者 XU Jiren ZHAO Zhixin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第1期135-144,共10页
This paper analyzes various earthquake fault types, mechanism solutions, stress field as well as other geophysical data to study the crust movement in the Tibetan plateau and its tectonic implications. The results sho... This paper analyzes various earthquake fault types, mechanism solutions, stress field as well as other geophysical data to study the crust movement in the Tibetan plateau and its tectonic implications. The results show that a lot of normal faulting type earthquakes concentrate in the central Tibetan plateau. Many of them are nearly perfect normal fault events. The strikes of the fault planes of the normal faulting earthquakes are almost in the N-S direction based on the analyses of the equal area projection diagrams of fault plane solutions. It implies that the dislocation slip vectors of the normal faulting type events have quite great components in the E-W direction. The extension is probably an eastward extensional motion, mainly a tectonic active regime in the altitudes of the plateau. The tensional stress in the E-W or WNW-ESE direction predominates the earthquake occurrence in the normal event region of the central plateau. A number of thrust fault and strike-slip fault type earthquakes with strong compressive stress nearly in the NNE-SSW direction occurred on the edges of the plateau. The eastward extensional motion in the Tibetan plateau is attributable to the eastward movement of materials in the upper mantle based on_seismo-tomographic results. The eastward extensional motion in the Tibetan plateau may be related to the eastward extrusion of hotter mantle materials beneath the east boundary of the plateau. The northward motion of the Tibetan plateau shortened in the N-S direction probably encounters strong obstructions at the western and northern margins. Extensional motions from the relaxation of the topography and/or gravitational collapse in the altitudes of the plateau occur hardly in the N-S direction. The obstruction for the plateau to move eastward is rather weak. 展开更多
关键词 normal faulting earthquake focal mechanism solution eastward extensional motion stressfield gravitational collapse
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LATE QUATERNARY FAULTING OF JIALI FAULT
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作者 Ren Jinwei 1, Shen Jun 1, Cao Zhongquan 2, Wang Yipeng 1(1 Institute of Geology, China Seismological Bureau, Beijing 100029,China, E\|mail:ren@eq\|igl.ac.cn 2 Seismological Bureau of Tibet Autonomous Region, Lhasa 850000,China) 《地学前缘》 EI CAS CSCD 2000年第S1期147-148,共2页
Jiali fault is one of the major faults in southeastern Tibetan plateau. From Naqu to Jiali along which the field investigation has been done, the fault roughly extends in N60W direction and consists of three segments ... Jiali fault is one of the major faults in southeastern Tibetan plateau. From Naqu to Jiali along which the field investigation has been done, the fault roughly extends in N60W direction and consists of three segments arranged in en echelon. From Luoermano to Esukongma (about 40km) where the fault is the northern boundary of the Sangdi basin that extend north\|south, late Quaternary surface ruptures have been found. Within this segment the creeks and gullies that cross the fault were offset and the displacements range from several meters to about 5km. The average slip rate during late Quaternary is about 10mm/a for this segment. An interesting phenomena is that the large displacement can only be found at those places where the fault is related to the basins that extend north\|south. Outside the basins, no convincing evidence has been found for late Quaternary surface ruptures and average slip rate for the whole fault is only about 3mm/a middle Pleistocene. It seems that these strike\|slip faults behave like a transform fault and the strike\|slip motion along them were a consequence of east\|west extension that creates the north\|south graben systems rather than the vice versa. 展开更多
关键词 faulting slip\|rate Jiali FAULT TIBETAN PLATEAU
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CENOZOIC FAULTING ALONG THE SOUTHEASTERN EDGE OF THE TIBETAN PLATEAU IN THE YANYUAN AREA AND ITS TECTONIC IMPLICATIONS
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作者 Wang Erchie 1, Burchfiel B. Clark 2 2 Department of Earth, Atmospheric and Planetary Sciences, MIT,Cambridge, MA 02139,UK) 《地学前缘》 EI CAS CSCD 2000年第S1期269-269,共1页
The southeastern edge of the Tibetan plateau is marked by several thrust sheets trending roughly in E\|W direction. The Yanyuan thrust sheet is bounded by three arcuate thrust belts, marked by high mountain ranges wit... The southeastern edge of the Tibetan plateau is marked by several thrust sheets trending roughly in E\|W direction. The Yanyuan thrust sheet is bounded by three arcuate thrust belts, marked by high mountain ranges with the Jinhe belt on the north, the Qianhe belt on the south and the Ninglang belt on the west. Within the Yanyuan thrust belt are sedimentary cover rocks of the Yangtze platform, with ages ranging from Sinian to Triassic. In the north, the thrust sheet is overlain by the Muli thrust sheet along the Jinhe belt, while in the south, it is underlain by the Kangdian paleoland along the Qianhe belt. The youngest rocks on the foot wall are late Eocene to Oligocene in age, indicating that the thrusting occurred in the late Tertiary. The top of the Yanyuan thrust belt is truncated by a flat erosion surface similar to that on the plateau to the north. Along a north\|dipping normal fault bordering the Yanyuan basin on the south, the erosion surface is tilted to the south against Triassic rocks. The basin is filled with coal\|bearing clastic sediments of Pliocene and early Pleistocene age, which gives the timing of the normal faulting. Based on the faulting pattern, we propose that the southeastern edge of the Tibetan plateau underwent a large amount of N\|S shortening and uplift along the Yanyuan thrust sheet in the late Tertiary, while the subsequent normal faulting that had occurred along the Yanyuan basin during the Pliocene and Pliocene can be interpreted to have accommodated gravitational collapse of the crust. 展开更多
关键词 southeastern EDGE of the Tibetan plateau Yanyuan thrust shee t CRUSTAL SHORTENING and UPLIFT normal faulting gravitational collapse
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Houston16:A stable geodetic reference frame for subsidence and faulting study in the Houston metropolitan area,Texas,U.S.
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作者 Timothy J.Kearns Guoquan Wang +3 位作者 Michael Turco Jennifer Welch Vasilios Tsibanos Hanlin Liu 《Geodesy and Geodynamics》 2019年第5期382-393,共12页
Houston,Texas,is one of the earliest regions to employ continuous GPS technology for land subsidence monitoring.Currently,there are over 200 permanent GPS stations located in the greater Houston area.The need for a co... Houston,Texas,is one of the earliest regions to employ continuous GPS technology for land subsidence monitoring.Currently,there are over 200 permanent GPS stations located in the greater Houston area.The need for a consistent and stable reference frame to precisely interpret local ground deformation has become critically important since the 1990s,because of the significant spreading of subsidence.We have established a stable Houston reference frame,designated Houston16,using publicly available GPS observations(>5 years)from 15 Continuously Operating Reference Stations(CORS)located outside of the greater Houston area.Applications of the reference frame in subsidence and faulting studies are demonstrated in this article.Houston16 is aligned in origin and scale with the International GNSS Reference Frame of 2008(IGS08).A 7-parameter method was employed to transform the GPS-derived positional time series from IGS08 to Houston16.The primary product of this study is the seven parameters for transforming Earth-Centered-Earth-Fixed XYZ coordinates from IGS08 to Houston16.The frame stability of Houston16 is approximately 1 mm/year.Houston16 will be updated every few years to mitigate degradation of the frame’s stability with time and to synchronize with future updates of the IGS reference frame. 展开更多
关键词 faulting GPS HOUSTON IGS08 Reference FRAME SUBSIDENCE
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GRAINREDUCTIONANDGROWTHINFAULTING
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作者 Duan Jiarui Kong Hua(Department of Geology, Central South University of Technology,Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第1期46-48,共3页
GRAINREDUCTIONANDGROWTHINFAULTINGANDNEWCLASSIFICATIONOFFAULTEDROCKSDuanJiaruiKongHua(DepartmentofGeology,Cen... GRAINREDUCTIONANDGROWTHINFAULTINGANDNEWCLASSIFICATIONOFFAULTEDROCKSDuanJiaruiKongHua(DepartmentofGeology,CentralSouthUniversi... 展开更多
关键词 REDUCTION GROWTH faulting classification〖J
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Neogene faulting and volcanism in the Victoria Land Basin of the Ross Sea, Antarctica
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作者 Mei Yue JinYao Gao +7 位作者 ChunFeng Li Chao Zhu XinZhi Fan Guochao Wu ZhongYan Shen Han Shi XiaoXian Cai YiDong Guo 《Earth and Planetary Physics》 EI CSCD 2022年第3期248-258,共11页
The Neogene Terror Rift in the Antarctic Victoria Land Basin(VLB)of the Ross Sea,Antarctica,is composed of the Discovery Graben and the Lee Arch.Many Neogene volcanoes are aligned in the north-south direction in the s... The Neogene Terror Rift in the Antarctic Victoria Land Basin(VLB)of the Ross Sea,Antarctica,is composed of the Discovery Graben and the Lee Arch.Many Neogene volcanoes are aligned in the north-south direction in the southern VLB,belonging to the McMurdo Volcanic Group.However,due to multiple glaciations and limited seismic data,the volcanic processes are still unclear in the northern VLB,especially in the Terror Rift.Multichannel seismic profiles were collected at the VLB from the 32nd Chinese National Antarctic Research Expedition(CHINARE).We utilized four seismic profiles from the CHINARE and additional historical profiles,along with gravity and magnetic anomalies,to analyze faults and stratigraphic characteristics in the northern Terror Rift and volcanism in the VLB.Negative flower structures found in the northern Terror Rift suggest that the Terror Rift was affected by dextral strike-slip faults extending from the northern Victoria Land(NVL).After the initial orthogonal tension,the rift transited into an oblique extension,forming a set of downward concaving normal faults and accommodation zones in the Terror Rift.On the Lee Arch,several imbricated normal faults formed and converged into a detachment fault.Under gravitational forces,the strata bent upward and formed a rollover anticline.Many deep faults and thin strata subjected to erosion facilitated volcanic activity.A brittle volcanic region in the VLB was affected by dextral strike-slip movements and east-west extension,resulting in two Neogene volcanic chains that connect three igneous provinces in the VLB:the Hallett,Melbourne,and Erebus Provinces.These two chains contain mud volcanoes with magnetic nuclei,volcanic intrusions,and late-stage volcanic eruptions.Volcanisms have brought about opposite polarities of magnetic anomalies in Antarctica,indicating the occurrence of multiple volcanic activities. 展开更多
关键词 Victoria Land Basin Terror Rift seismic stratigraphy gravity and magnetic modeling faulting Neogene volcanic intrusion
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Cenozoic Denudation and Vertical Faulting History of the Central Segment of the Longmenshan Thrust Belt
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作者 TAN Xibin XU Xiwei +2 位作者 LEE Yuanhsi KANG Wenjun ZHAO Shiliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1541-1542,共2页
Objective The uplift process and uplift mechanism of the Tibetan Plateau has been a research focus among geologists in recent years. This work put emphasis on the Cenozoic exhumation histories of the blocks bounded by... Objective The uplift process and uplift mechanism of the Tibetan Plateau has been a research focus among geologists in recent years. This work put emphasis on the Cenozoic exhumation histories of the blocks bounded by the major faults at the central segment of the Longmenshan thrust belt, and the vertical faulting history, including the starting time and the total vertical displacement, of the major faults. Then we quantitatively established a complete active process for the central segment of the Longmenshan thrust belt, combining with the previous geophysical data in the deep and geologcial data. This study is critical for deeply and completely understanding the Cenozoic uplift history of the Longmenshan, and also provides thermochronology constraints to the different models for the uplift of the eastern margin of the Tibetan Plateau. 展开更多
关键词 Cenozoic Denudation and Vertical faulting History of the Central Segment of the Longmenshan Thrust Belt
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Quaternary Geology and Faulting in the Damxung-Yangbajain Basin 被引量:6
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作者 WUZhonghai ZHAOXitao +3 位作者 WUZhenhan JIANGWan HUDaogong ZHOUChunjing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期273-282,共10页
The detailed geological mapping, conducted in the Damxung-Yangbajain basin, shows that there are many types of deposits formed since the Pliocene. The oldest sediments are formed during the Pliocene. The most prominen... The detailed geological mapping, conducted in the Damxung-Yangbajain basin, shows that there are many types of deposits formed since the Pliocene. The oldest sediments are formed during the Pliocene. The most prominent sediments are three sets of moraines and fluvioglacial deposits. The ESR, U-series and OSL dates indicate they are formed about 700-500 ka B.P., 250-125 ka B.P. and 75-12 ka B.P. respectively and indicate that there are three glacial periods since the mid-Pleistocene in the Nyainqentanglha Range. Along the southeast side of the Nyainqentanglha Range, the main southeast dipping fault zone which bounds the Damxung-Yangbajain Graben on its western edge was mapped. The fault zone consists of three secondary fault zones and their initiation ages that the fault zones became active gradually decrease southeastward. Prominent faulting occurred in about 700-500 ka B.P., 350-220 ka B.P., -140 ka B.P. and 70-50 ka B.P. since the mid-Pleistocene. The height of fault scarps which offset the sediments formed since the mid-Pleistocene suggest that the vertical slip rates change between 0.4 -2 mm/a and the cumulative average vertical movement at rates of 1.1±0.3 mm/a during the Quaternary period and the Holocene vertical throw rate is 1.4±0.6 mm/a along the fault zones on the western side of the Damxung-Yangbajain Graben. 展开更多
关键词 Qinghai-Tibet plateau NYAINQENTANGLHA north-south trending graben active fault GLACIATION
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Dextral-Slip Thrust Faulting and Seismic Events of the Ms 8.0 Wenchuan Earthquake,Longmenshan Mountains,Eastern Margin of the Tibetan Plateau 被引量:8
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作者 WU Zhenhan DONG Shuwen +2 位作者 Patrick J. BAROSH ZHANG Zuoheng LIAO Huaijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第4期685-693,共9页
Dextral-slip thrust movement of the Songpan-Garze terrain over the Sichuan block caused the Ms 8.0 Wenchuan earthquake of May 12, 2008 and offset the Central Longmenshan Fault (CLF) along a distance of -250 km. Disp... Dextral-slip thrust movement of the Songpan-Garze terrain over the Sichuan block caused the Ms 8.0 Wenchuan earthquake of May 12, 2008 and offset the Central Longmenshan Fault (CLF) along a distance of -250 km. Displacement along the CLF changes from Yingxiu to Qingchuan. The total oblique slip of up to 7.6 m in Yingxiu near the epicenter of the earthquake, decreases northeastward to 5.3 m, 6.6 m, 4.4 m, 2.5 m and 1.1 m in Hongkou, Beichuan, Pingtong, Nanba and Qingchuan, respectively. This offset apparently occurred during a sequence of four reported seismic events, EQ1-EQ4, which were identified by seismic inversion of the source mechanism. These events occurred in rapid succession as the fault break propagated northeastward during the earthquake. Variations in the plunge of slickensides along the CLF appear to match these events. The Mw 7.5 EQ1 event occurred during the first 0-10 s along the Yingxiu-Hongkou section of the CLF and is characterized by 1.7 m vertical slip and vertical slickensides. The Mw 8.0 EQ2 event, which occurred during the next 10-42 s along the Yingxiu-Yanziyan section of the CLF, is marked by major dextralslip with minor thrust and slickensides plunging 25°-35° southwestward. The Mw 7.5 EQ3 event occurred during the following 42-60 s and resulted in dextral-slip and slickensides plunging 10° southwestward in Beichuan and plunging 73° southwestward in Hongkou. The Mw 7.7 EQ4 event, which occurred during the final 60-95 s along the Beichuan-Qingchuan section of the CLF, is characterized by nearly equal values of dextral and vertical slips with slickensides plunging 45°-50° southwestward. These seismic events match and evidently controlled the concentrations of landslide dams caused by the Wenchuan earthquake in Longmenshan Mountains. 展开更多
关键词 Ms 8.0 Wenchuan earthquake co-seismic slip slickensides seismic events Central Longmenshan Fault Eastern Tibetan Plateau
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Faulting, magmatism and crustal oceanization of the Okinawa Trough 被引量:5
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作者 GAO Jinyao ZHANG Tao +2 位作者 FANG Yinxia YANG Chuanguo MEI Sai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第3期40-49,共10页
The paper focuses on the characteristics of faulting and magmatism of the Okinawa Trough and the relation between them. En-echelon grabens are ranked oblique to the continental shelf edge uplift, and the Longwang upli... The paper focuses on the characteristics of faulting and magmatism of the Okinawa Trough and the relation between them. En-echelon grabens are ranked oblique to the continental shelf edge uplift, and the Longwang uplift, the rifting block ridge in the northern segment and the "Mianhua uplift" in the southern segment have possibly preserved characteristics of volcanism and magmatism occurring with those rifting phases. The clockwise rotation of the southern Ryukyu Islands, driven by collision between Luzon and Taiwan, has played a key role in the crustal oceanization, enhancing the crustal extension of the southern segment and inducing volcanic magmatism in those grabens, among which the Yaeyama graben is a typical example of the presence of oceanic crust. Faulting and magmatism were mainly migrating towards the island arc asymmetrically. The crustal oceanization of the Okinawa Trough is difficultly interpreted by the linear magnetic anomaly model, which is fit for the symmetric spreading of the mid-oceanic ridges. 展开更多
关键词 Okinawa Trough fault GRABEN UPLIFT oceanic crust volcanic magma
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Faulting on the Anninghe fault zone,Southwest China in Late Quaternary and its movement model 被引量:3
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作者 何宏林 池田安隆 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第5期571-583,共13页
The Anninghe fault is one of the significant earthquake-generating fault zones in the Southwest China. Local historical record shows that a M2≥7 strong earthquake occurred in the year of 1536. On the basis of the det... The Anninghe fault is one of the significant earthquake-generating fault zones in the Southwest China. Local historical record shows that a M2≥7 strong earthquake occurred in the year of 1536. On the basis of the detailed air-photographic interpretation and field investigation, we have acquired the following knowledge: ① The average sinistral strike-slip rate since the Late Pleistocene is about 3~7 mm/a; ② There is important reverse faulting along the fault zone besides the main left-lateral strike-slip motion, and the shortening rate across the Anninghe fault zone due to the reverse faulting is about 1.7-4.0 mm/a. If the Xianshuihe fault zone is simply partitioned into the Anninghe and Daliangshan faults, we can also get a slip rate of 3-7 mm/a along the Daliangshan fault zone, which is the same as that on the Anninghe fault zone. Moreover, on the basis of our field investigation and the latest knowledge concerning the active tectonics of Tibetan crust, we create a dynamic model for the Anninghe fault zone. 展开更多
关键词 active fault reverse fault slip rate Anninghe fault
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Effect of faulting on coal burst——A numerical modelling study 被引量:3
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作者 Lu Chen Baotang Shen Bongani Dlamini 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第5期739-743,共5页
Coal burst occurrence on roadways has always been a major concern in deep underground coal mines,especially under complex geological conditions. To evaluate the effect of faulting on coal burst, the stress concentrati... Coal burst occurrence on roadways has always been a major concern in deep underground coal mines,especially under complex geological conditions. To evaluate the effect of faulting on coal burst, the stress concentration in the vicinity a reverse fault was analysed considering the geological history of the fault formation where high horizontal stresses led to the initiation and propagation of the reverse fault.Various in situ stresses and mechanical parameters of the fault, including the ratio of horizontal stress to vertical stress were used to analyse the state of fault. Numerical modelling was conducted using two and three dimensional distinct element models(UDEC and 3 DEC) based on a geotechnical conditions of an Australian underground coal mine. The formation process of reverse fault was simulated to evaluate the stress characteristics in the coal seam and the immediate roof and floor near the fault. The results show that, both the horizontal and vertical stress in footwall were higher than those in hanging wall after the formation of the reverse fault. The stress condition near fault was complicated due to complex geology in the coal measures, and the vertical stress peaked in the footwall at a distance of about 160 m from the fault. When a roadway was excavated, stress concentration occurred at both the roadway face and ribs, which reached as high as 38 MPa in the ribs at a depth of 500 m. This will significantly elevate the risk of dynamic instability of the roadway such as coal burst. The stress concentration zone in the footwall can be considered as a hazardous zone near the reverse fault. This study provides a general reference for analysis of roadway stability affected by faults. 展开更多
关键词 COAL BURST REVERSE FAULT Stress CHARACTERISTIC Safety factor
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Modeling of normal faulting in the subducting plates of the Tonga,Japan,Izu-Bonin and Mariana Trenches:implications for near-trench plate weakening 被引量:4
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作者 ZHOU Zhiyuan LIN Jian ZHANG Fan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第11期53-60,共8页
The plate flexure and normal faulting characteristics along the Tonga, Japan, Izu-Bonin and Mariana Trenches are investigated by combining observations and modeling of elastoplastic deformation of the subducting plate... The plate flexure and normal faulting characteristics along the Tonga, Japan, Izu-Bonin and Mariana Trenches are investigated by combining observations and modeling of elastoplastic deformation of the subducting plate. The observed average trench relief is found to be the smallest at the Japan Trench(3 km) and the largest at the Mariana Trench(4.9 km), and the average fault throw is the smallest at the Japan Trench(113 m) and the largest at the Tonga Trench(284 m). A subducting plate is modeled to bend and generate normal faults subjected to three types of tectonic loading at the trench axis: vertical loading, bending moment, and horizontal tensional force. It is inverted for the solutions of tectonic loading that best fit the observed plate flexure and normal faulting characteristics of the four trenches. The results reveal that a horizontal tensional force(HTF) for the Japan Trench is 33%, 50% and 60% smaller than those of the Mariana, Tonga and Izu-Bonin Trenches, respectively. The normal faults are modeled to penetrate to a maximum depth of 29, 23, 32 and 32 km below the sea floor for the Tonga,Japan, Izu-Bonin and Mariana Trenches, respectively, which is consistent with the depths of relocated normal faulting earthquakes in the Japan and Izu-Bonin Trenches. Moreover, it is argued that the calculated horizontal tensional force is generally positively correlated with the observed mean fault throw, while the integrated area of the reduction in the effective elastic thickness is correlated with the trench relief. These results imply that the HTF plays a key role in controlling the normal faulting pattern and that plate weakening can lead to significant increase in the trench relief. 展开更多
关键词 normal fault geodynamic model plate weakening flexural bending elasto-plastic deformation
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Relationship between salt diapirism and faulting in the central structural belt of the Dongying sag,Bohai Gulf basin,China 被引量:3
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作者 YUJianguo LISanzhong +3 位作者 WANGJinduo TIMOTHYMKusky WANGXinhong LUShengqiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第2期28-42,共15页
Many growth faults developed in the Dongying sag of the Jiyang depression of the Bohai Gulf basin, China. These normal growth faults consist of flower-like grabens in the hanging walls of the major faults, accompanied... Many growth faults developed in the Dongying sag of the Jiyang depression of the Bohai Gulf basin, China. These normal growth faults consist of flower-like grabens in the hanging walls of the major faults, accompanied by reverse dragging. The central structural belt is an important structural unit in the Dongying sag, and is divided into a series of small blocks by these faults. These internal blocks can be classified into five structural classes, including parallel blocks, arc-shape blocks, plume-like blocks, ring-radial blocks, and splay blocks. It is shown that these complicated block classes and the 'negative flower-like' fault associations in the central structural belt resulted from regional NNW-SSE extension accompanying local salt diapirism and related reverse dragging, rather than strike-slip faulting. On the basis of the diapirism strength, diapers in the central structural belt can be divided into lower salt ridges and pillows, and blind piercing structures. Diapirs are mainly composed of some salts with a little soft mudstone and gypsum. These structures began forming during deposition of the Sha 3 member and terminated during deposition of the Guangtao formation. 展开更多
关键词 Dongying sag FAULT SALT DIAPIRISM Bohai Gulf
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Late Paleozoic Element Migration and Accumulation under Intracontinental Sinistral Strike-slip Faulting in the West Junggar Orogenic Belt, NW China 被引量:1
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作者 WANG Ye CHEN Xuanhua +5 位作者 NIE Lanshi DING Weicui WANG Xueqiu XU Shenglin MA Feizhou HAN Lele 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第6期2012-2030,共19页
The migration,accumulation and dispersion of elements caused by tectonic dynamics have always been a focus of attention,and become the basis of tectono-geochemistry.However,the effects of faulting,especially strike-sl... The migration,accumulation and dispersion of elements caused by tectonic dynamics have always been a focus of attention,and become the basis of tectono-geochemistry.However,the effects of faulting,especially strike-slip faulting,on the adjustment of geochemical element distribution,are still not clear.In this paper,we select the West Junggar Orogenic Belt(WJOB),NW China,as a case study to test the migration behavior of elements under tectonic dynamics.The WJOB is dominated by NE-trending large-scale sinistral strike-slip faults such as the Darabut Fault,the Mayile Fault,and the Baerluke Fault,which formed during the intracontinental adjustment under N-S compression during ocean-continental conversion in the Late Paleozoic.Geochemical maps of 13 elements,Al,W,Sn,Mo,Cu,Pb,Zn,As,Sb,Hg,Fe,Ni,and Au,are analyzed for the effects of faulting and folding on element distribution at the regional scale.The results show that the element distribution in the WJOB is controlled mainly by two mechanisms during tectonic deformation:first is the material transporting mechanism,where the movement of geological units is consistent with the direction of tectonic movement;second is the diffusion mechanism,especially by tectonic pressure dissolution driven by tectonic dynamics,where the migration of elements is approximately perpendicular or opposite to the direction of tectonic movement.We conclude that the adjustment of element distributions has been determined by the combined actions of transporting and diffusion mechanisms,and that the diffusion mechanism plays an important role in the formation of geochemical Au blocks in the WJOB. 展开更多
关键词 tectono-geochemistry strike-slip fault system element distribution GOLD West Junggar Central Asian Orogenic Belt
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