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基于TM遥感影像的构造地貌解译和野外活动断层滑动矢量的测量和分析 ,阐述了太行山南缘断裂带第四纪左旋走滑活动的构造和地貌标志 ,反演了断裂变形的构造应力场 ,探讨了太行山南缘断裂带左旋走滑活动的区域运动学意义。研究表明 ,第四纪时期太行山南缘断裂带是一条斜张左旋走滑断裂。断层滑动矢量观测显示新近纪以来有 2期引张应力作用 :早期为NE -SW向引张 ,晚期为NNW -SSE向引张 ,这个观测结果与渭河地堑盆地的新近纪—第四纪 2期引张构造应力场一致。根据华北盆地构造资料推断 ,太行山南缘断裂带向东延伸与盆地内的泌阳 -开封 -商丘断陷带相接 ,共同构成了南华北和北华北 2个断陷区的构造边界。指出该断裂带作为南华北块体北缘 ,其新构造时期的斜张左旋走滑活动与南部秦岭断裂系左旋走滑活动一致 ,它们组成了一个宽阔的、向东撒开的、弥散型分布的左旋走滑形变带 ,调节着华南地块相对于华北地块向SEE方向的构造挤出 相似文献
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拉脊山断裂带在遥感影像上具有明显的线性构造特征,由拉脊山北缘断裂带和拉脊山南缘断裂带向北东凸出的弧形挤压逆冲断裂带构成,成为北侧的西宁—民和盆地、南侧的循化—化隆盆地和东侧的临夏盆地等多个晚新生代断陷盆地的边界,拉脊山北缘断裂带全长230km,由数段弧状不连续的断裂带组成。拉脊山南缘断裂带全长220km,由5段不连续宽缓波状断裂带组成,其左旋活动形成了拉张型的山间盆地——千户盆地,左旋水平位移180～640m不等。历史上沿拉脊山南、北两侧发生过20余次5级左右中等破坏性地震,这与遥感解译该断裂带的几何特征相一致。 相似文献
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兰州地区活动构造的基本特征 总被引：5，自引：0，他引：5
兰州地区发育了NWW向和NWW向2组主导性活动构造带。大致以河口为界，东部地区主要为NWW向的马衔山－兴隆山左旋逆走滑活动断裂系，其新活动明显，是区内的主要控震断裂，1125年兰州7级地震就发生在其中的马衔山北缘断裂带的西端。河口以西为拉脊山北缘断裂和庄浪河断裂等1组NWW向的弧形逆冲断褶带，变形方式以断裂扩展褶皱为主，其新活动可能导致了138年金城－陇西63／4级地震、1440年永登61／4级地震和1995年永登5.8级地震的发生。兰州市区所在的兰州盆地则夹持在上述2组活动构造之间，其内同样发育了NWW向和NWW向的次级断裂，如刘家堡断裂、金城关断裂、雷坛河断裂及深沟桥断裂等，其上具有孕育和发生中强震的构造条件。 相似文献
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阿尔泰构造带的活动断裂主要为NW—NNW向。按构造位置可分为阿尔泰西缘活动断裂带、阿尔泰中央活动断裂带和阿尔泰东缘活动断裂带。阿尔泰东缘活动构造带由科布多(Hovd)活动断裂带、哈尔乌苏湖(Har Us)活动断裂带2条大型右旋走滑活动断裂和中间的挤压盆地带构成。在2条走滑断裂带上,前人发现多处地震地表破裂带。通过对阿尔泰东缘构造带中南段地区的野外调查,在哈尔乌苏湖断裂带中段的Jargalant断裂、科布多断裂带南段的Tugen gol断裂上新发现地震地表破裂带。其中,沿Jargalant断裂地震地表破裂带长约50km,右旋位错量约4~5m,是一次规模大、活动较新的破裂事件。可见,在阿尔泰东缘活动断裂带的不同断裂段上均有保存较好的地震地表破裂,显示阿尔泰东缘是活动强烈的地震构造带 相似文献
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阿拉善地块南缘发育了由5条走向近EW、向西收敛、向东撒开的断裂组成的断裂束,每条断裂长度一般>100km,控制第四纪盆地呈EW向长条状展布,卫片上线性影像清晰,晚第四纪以来表现出左旋走滑活动的特点。断裂束西段的金塔南山断裂与阿尔金断裂带东段的宽滩山段趋于交会,并与文殊山构造隆起之间构成构造转换关系。分析认为金塔南山断裂以及整个阿拉善南缘断裂束是阿尔金断裂左旋运动的东延部分,断裂束在平面上“帚状”的、向东撒开的构造样式有利于走滑运动量的分解、消减和吸收,符合走滑断裂末端的构造特点。阿拉善南缘断裂束的左旋走滑活动有可能是阿尔金断裂带进一步向东扩展的结果,其时代可能发生于早更新世末—中更新世初 相似文献
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北西向张家口－蓬莱断裂带由近２０条北西至北西西向断裂组成,是一条对新生代区域地质构造发育起到重要控制作用的地壳构造带。断裂带新生代活动由中部向西北和东南部发展,总体表现左旋走滑性质。断裂带有山西断陷盆地带等几条北东向活动构造带与之交汇,形成北西和北东向两组断裂相互交切的构造组合,出现５个复杂的构造交接段。６级以上强震和大多数中小地震群集于这些地段,其中北西和北东向断裂都可能发生地震,显示共轭破裂错动特征,但北东向断裂发生的地震强度较大。张北－尚义６．２级地震发生于断裂带与山西断陷盆地带交接段的西缘,是断裂带向西北扩展的结果 相似文献
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2008年5月12日四川汶川Ms8.0地震是一条陆内活动逆断裂带最新活动的结果.地震震源断裂沿龙门山构造带中央断裂发生斜滑作用和沿前山断裂发生纯逆断裂作用,断裂产状前者陡后者缓,垂直位移前者大后者小,这是一条少见的具有右旋走滑特征的挤压性质双断坡破裂,它是深部斜滑断裂在上地壳脆性域发生应变分解的结果.地震地表破裂带的分段活动和位移分布、地震波反演、余震空间分布、主震和余震震源机制解都说明这一条活动断裂带的活动机制和震源断裂破裂机制的复杂性.北西向小鱼洞左旋走滑破裂带是调节北东向破裂带中缩短量不同的破裂段之间的捩断裂,但由于震源断裂西南段经受着强烈挤压,左旋走滑的小鱼洞断裂也具有明显的挤压分量.在中央断裂这一条走滑逆冲和逆走滑性质的断裂和破裂带中出现的走滑正断裂控制的沙坝沟槽是在一个特殊的构造和地貌条件下,由震源断裂滑动和重力共同作用的结果,重力作用加大了该段破裂的正断层型垂直位移量,它不能真正代表震源断裂的最大地表垂直位移. 相似文献
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2017年四川九寨沟MS7.0地震是继2008年汶川MS8.0地震和2013年芦山MS7.0地震之后，青藏高原东缘在不到十年的时间内发生的第三个震级MS7.0以上的强震.这次地震发生在东昆仑断裂带东端，作为青藏高原东北缘的一条大型左旋走滑断裂带，东昆仑断裂带与东端其它构造之间的转换关系仍不清楚，因区内地质构造和地形复杂，东昆仑断裂带东端的主要构造仍缺少深入的研究.本文在总结区域地震构造活动特征、历史地震和现代地震基础上，通过东昆仑断裂带东端已有的和最近开展的活动构造定量研究结果，并结合现今GPS变形场资料和2017年九寨沟MS7.0地震灾害特征分析，发现东昆仑断裂带最东段塔藏断裂上的左旋走滑除了一小部分继续向东传播转移到文县断裂带上外，大部分转化为其南侧的龙日坝断裂带北段、岷江断裂和虎牙断裂上的近东西向地壳缩短，这可能是岷山隆起的构造机制，而2017年九寨沟MS7.0地震正是左旋走滑的东昆仑断裂带在东端继续向东扩展的结果. 相似文献
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根据历史地震资料考证、现场考察与综合分析，1765年5月1日发生在临洮南的一次中强破坏性地震其极震区位于卓尼、康乐交界的洮河连麓盆地附近的柳林、宗石一带，其名称应修改为卓尼-康乐地震，震级约5 1/2~6级，震中烈度可达Ⅷ度，极震区长轴方向大致与该区西秦岭北缘断裂带西段的锅麻滩断裂段东端相吻合。根据野外实地调查，锅麻滩断裂在极震区附近存在新活动的地质地貌现象，出露的断层剖面揭示出以左旋走滑为主兼具向北倾的正断特征，宏观地貌上沿断裂保留有断层陡坎、冲沟左旋位错等地貌标志。结合该区域构造应力场分析，本次卓尼-康乐地震发生在锅麻滩断裂段与漳县-黄香沟断裂段之间的左阶拉分区，是受区域应力影响引起断裂带在交汇部位与端点处应力集中所致。综合分析认为，锅麻滩断裂带东端是此次地震的发震构造。 相似文献
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A Preliminary Study on the New Activity Features of the Lajishan Mountain Fault Zone in Qinghai Province 总被引：3，自引：0，他引：3
Yuan Daoyang 《中国地震研究》2005,19(4):391-401
INTRODUCTIONThe Lajishan Mountainlies onthe northeastern margin of Qinghai_Xizang(Tibet)plateau.It is ageomorphic gradient zone,separatingthe hinterland of Tibetfromthe Loess plateau.The Lajishanfaultis a product of Caledonian movement,havingexperienced m… 相似文献
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本文利用青藏高原东北缘地区1991—2015年的GPS速度场资料, 基于弹性球面块体模型获得了区域活动断裂的滑动速率, 并讨论了断裂滑动速率分配的动力学意义。 反演结果表明, 青藏高原东北缘地区主要块体以北东向并兼顺时针旋转运动为主; 区域断裂平均闭锁深度为17 km; 另外, 各主要断裂滑动速率也不尽相同。 其中, 阿尔金断裂、 东昆仑断裂左旋走滑速率为10～12 mm/a, 祁连—海原断裂左旋走滑速率为3～5 mm/a, 鄂拉山断裂、 拉脊山断裂右旋走滑速率为1～3 mm/a。 阿尔金断裂、 祁连—海原断裂、 东昆仑断裂的走滑速率被其端部的山脉隆起和逆冲断裂所吸收和转换, 鄂拉山断裂和拉脊山断裂则起到了调节块体间运动平衡的作用。 相似文献
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帕米尔高原位于地中海－喜马拉雅地震带上，晚新生代以来随着印度板块向欧亚板块持续不断地挤压汇聚，其构造运动是欧亚大陆最强烈的地区。高原腹地发育一系列近SN向正断层，包括近SN向的塔什库尔干正断层所处的帕米尔中部现代区域的构造应力场以EW向水平拉张为主。2016年11月25日发生的阿克陶MS 6.7级地震的发震构造为塔什库尔干断层分支的NWW向木吉盆地北缘断层，其具有右旋走滑兼正断性质。地震在震中附近产生同震地表形变带，全长约1km，呈近SN－NNE向水平拉伸，发育近EW—NWW向的张裂缝，为地震破裂的产物，张裂缝的最大水平拉伸位移量和最大垂直位移量分别为46cm和16cm。地表破裂带中的NE和NW向张剪裂缝只是连接贯通这些雁列的张裂缝，其水平相对位移量取决于张裂缝的水平拉伸量和张裂缝之间的几何关系。地表形变带表现的拉张性质与帕米尔高原腹地区域现代应力场最大主压应力为垂直向基本一致，可能与深部热物质上涌造成的上地壳拉伸有关。而地表形变带呈近SN向水平拉张，与区域近EW向拉张应力场之间存在显著差异，这可能是木吉盆地北缘右旋走滑正断层阶区局部应力场调整的结果。 相似文献
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Wang Ruobai 《中国地震研究》2005,19(3):327-337
INTRODUCTIONThe Zhangjiakou-Penglai fault zone has drawnextensive attentionfromseismologists and geologistssince it was determinedinthe1980’s(Zheng Binghua,et al.,1981).Ma Xingyuan,et al.(1989)consideredit asthe north boundaryof North China sub-block.Int… 相似文献
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深地震反射剖面揭示的海原断裂带深部几何形态与地壳形变 总被引：9，自引：5，他引：4
由于活动的青藏高原不断的隆升和推挤作用,在西南向东北的推挤作用和周缘块体的阻挡以及东北缘内部块体挤压形变的作用下,形成了多个走向不同的青藏高原东北缘构造体系.新生代构造变形和地震活动强烈,区内分布多条大型深断裂带.海原断裂是青藏高原东北缘发育的弧形活动断裂带中规模最大、活动最为强烈的一条左旋走滑型断裂带,是重要的大地构造区边界,也是控制现今强震活动的活断层.本文利用2009年完成的高分辨率深地震反射剖面的北段资料,对其进行初步构造解释,揭示出海原断裂带的深部几何形态和其两侧地壳上地幔细结构.结果显示海原断裂并不是简单的陡立或者较缓,其几何形态随着深度变化.在海原断裂之下的Moho并未错断的反射特征显示海原断裂并不是直接错断莫霍面的超壳断裂.海原断裂带及两侧岩石圈结构和构造样式的研究为探讨青藏高原东北缘岩石圈变形机制提供地震学依据. 相似文献
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LI Wei DONG YunPeng GUO AnLin LIU XiaoMing LIU YiQun ZHA XianFeng ZHANG KuaiLe 《中国科学:地球科学(英文版)》2013,56(10):1639-1653
The Qinling Orogenic Belt is divided commonly by the Fengxian-Taibai strike-slip shear zone and the Huicheng Basin into the East and West Qinling mountains,which show significant geological differences after the Indosinian orogeny.The Fengxian-Taibai fault zone and the Meso-Cenozoic Huicheng Basin,situated at the boundary of the East and West Qinling,provide a natural laboratory for tectonic analysis and sedimentological study of intracontinental tectonic evolution of the Qinling Orogenic Belt.In order to explain the dynamic development of the Huicheng Basin and elucidate its post-orogenic tectonic evolution at the junction of the East and West Qinling,we studied the geometry and kinematics of fault zones between the blocks of West Qinling,as well as the sedimentary fill history of the Huicheng Basin.First,we found that after the collisional orogeny in the Late Triassic,post-orogenic extensional collapse occurred in the Early and Middle Jurassic within the Qinling Orogenic Belt,resulting in a series of rift basins.Second,in the Late Jurassic and Early Cretaceous,a NE-SW compressive stress field caused large-scale sinistral strike-slip faults in the Qinling Orogenic Belt,causing intracontinental escape tectonics at the junction of the East and West Qinling,including eastward finite escape of the East Qinling micro-plate and southwest lateral escape of the Bikou Terrane.Meanwhile,the strike-slip-related Early Cretaceous sedimentary basin was formed with a right-order echelon arrangement in sinistral shear zones along the southern margin of the Huicheng fault.Overall during the Mesozoic,the Huicheng Basin and surrounding areas experienced four tectonic evolutionary stages,including extensional rift basin development in the Early and Middle Jurassic,intense compressive uplift in the Late Jurassic,formation of a strike-slip extensional basin in the Early Cretaceous,and compressive uplift in the Late Cretaceous. 相似文献
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2014年于田7.3级地震的发震构造及动力学背景的初步分析 总被引：3，自引：0，他引：3
2004年2月12日新疆维吾尔自治区于田县发生了Ms7.3级地震,其发震断裂为阿尔金断裂带西南段的贡嘎错断裂带.由于地处高山无人区,存在区域历史地震漏记,但1970年以来5级以上地震活动是完整的,近20年来强震活动增强.综合分析认为,2008年于田Ms7.3地震可能加速了本次地震的发生.根据经验统计关系估计,2014年于田地震的同震地表破裂为30-40km,最大水平位错量为1.0-1.5m,地震的复发周期为300-400年.通过阿尔金断裂上前人资料和区域构造的综合分析,认为2014年于田地震是在青藏高原向北东运动背景下左旋走滑的阿尔金断裂向南西端扩展的结果. 相似文献
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ANALYSIS OF EVOLUTION OF THE RIYUESHAN FAULT SINCE LATE PLEISTOCENE USING STRUCTURAL GEOMORPHOLOGY 
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下载免费PDF全文 The northeastern margin of Tibetan plateau is an active block controlled by the eastern Kunlun fault zone, the Qilian Shan-Haiyuan fault zone, and the Altyn Tagh fault zone. It is the frontier and the sensitive area of neotectonic activity since the Cenozoic. There are widespread folds, thrust faults and stike-slip faults in the northeastern Tibetan plateau produced by the intensive tectonic deformation, indicating that this area is suffering the crustal shortening, left-lateral shear and vertical uplift. The Riyueshan Fault is one of the major faults in the dextral strike-slip faults systems, which lies between the two major large-scale left-lateral strike-slip faults, the Qilian-Haiyuan Fault and the eastern Kunlun Fault. In the process of growing and expanding of the entire Tibetan plateau, the dextral strike-slip faults play an important role in regulating the deformation and transformation between the secondary blocks. In the early Quaternary, because of the northeastward expansion of the northeastern Tibetan plateau, tectonic deformations such as NE-direction extrusion shortening, clockwise rotation, and SEE-direction extrusion occurred in the northeastern margin of the Tibetan plateau, which lead to the left-lateral slip movement of the NWW-trending major regional boundary faults. As the result, the NNW-trending faults which lie between these NWW direction faults are developed. The main geomorphic units developed within the research area are controlled by the Riyueshan Fault, formed due to the northeastward motion of the Tibet block. These geomorphic units could be classified as:Qinghai Lake Basin, Haiyan Basin, Datonghe Basin, Dezhou Basin, and the mountains developed between the basins such as the Datongshan and the Riyueshan. Paleo basins, alluvial fans, multiple levels of terraces are developed at mountain fronts. The climate variation caused the formation of the geomorphic units during the expansion period of the lakes within the northeastern Tibetan plateau. There are two levels of alluvial fans and three levels of fluvial terrace developed in the study area, the sediments of the alluvial fans and fluvial terraces formed by different sources are developed in the same period. The Riyueshan Fault connects with the NNW-trending left-lateral strike-slip north marginal Tuoleshan fault in the north, and obliquely connects with the Lajishan thrust fault in the south. The fault extends for about 180km from north to south, passing through Datonghe, Reshui coal mine, Chaka River, Tuole, Ketu and Xicha, and connecting with the Lajishan thrusts near the Kesuer Basin. The Riyueshan Fault consists of five discontinuous right-step en-echelon sub-fault segments, with a spacing of 2~3km, and pull-apart basins are formed in the stepovers.
The Riyueshan Fault is a secondary fault located in the Qaidam-Qilian active block which is controlled by the major boundary faults, such as the East Kunlun Fault and the Qilian-Haiyuan Fault. Its activity characteristics provide information of the outward expansion of the northeastern margin of Tibet. Tectonic landforms are developed along the Riyueshan Fault. Focusing on the distinct geomorphic deformation since late Pleistocene, the paper obtains the vertical displacement along the fault strike by RTK measurement method. Based on the fault growth-linkage theory, the evolution of the Riyueshan Fault and the related kinetic background are discussed. The following three conclusions are obtained:1)According to the characteristics of development of the three-stage 200km-long steep fault scarp developed in the landforms of the late Pleistocene alluvial fans and terraces, the Riyueshan Fault is divided into five segments, with the most important segment located in the third stepover(CD-3); 2)The three-stage displacement distribution pattern of the Riyueshan Fault reveals that the fault was formed by the growths and connections of multiple secondary faults and is in the second stage of fault growth and connection. With CD-3 as the boundary, the faults on the NW side continue to grow and connect; the fault activity time on the SE side is shorter, and the activity intensity is weaker; 3)The extreme value of the fault displacement distribution curve indicates the location of strain concentration and stress accumulation. With the stepover CD-3 as the boundary, the stress and strain on NW side are mainly concentrated in the middle and fault stepovers. The long-term accumulation range of stress on the SE side is relatively dispersed. The stress state may be related to the counterclockwise rotation inside the block under the compression of regional tectonic stress. 相似文献