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1.
青藏高原中部色林错—伦坡拉逆冲推覆构造系统   总被引:1,自引:0,他引:1       下载免费PDF全文
通过野外地质观测结合地震反射剖面综合构造解释,在青藏高原中部色林错—伦坡拉古近纪沉积凹陷及邻区厘定3条较大规模的逆冲推覆构造,由逆冲断层、逆冲岩席、飞来峰、构造窗及伴生褶皱组成。沿班公—怒江缝合带发育赛布错—扎加藏布逆冲推覆构造,伦坡拉盆地北部发育双重推覆构造,拉萨地块北缘发育色林错—吴如错逆冲推覆构造,估算推覆距离分别为38~50 km。羌塘地块南缘自北向南逆冲推覆,拉萨地块北缘自南向北逆冲推覆,两者对冲导致色林错古近纪盆地及沉积地层发生比较强烈的褶皱变形,形成宽约20 km大型向斜构造。色林错—伦坡拉逆冲推覆构造运动开始时间为晚白垩世晚期,古近纪不同时期均发育逆冲断层,前锋逆冲断层和底部拆离滑脱构造主要形成时期为古近纪晚期—中新世早期。古近纪逆冲推覆构造对伦坡拉和色林错河湖相沉积盆地、烃源岩形成演化、油气成藏及保存条件具有显著控制作用。  相似文献   

2.
藏北改则新生代早期逆冲推覆构造系统   总被引:2,自引:0,他引:2  
藏北改则及邻区新生代早期发育大型逆冲推覆构造系统,由不同方向的逆冲断层、不同时代的构造岩片、不同规模的飞来峰和构造窗、不同类型的褶皱构造组成。羌塘中部发育羌中薄皮推覆构造,石炭系板岩和二叠系白云质灰岩自北向南逆冲推覆于上白垩统与古近系红层之上,形成大型逆冲岩席和弧形逆冲断层,原地系统古近纪红层下伏三叠系—侏罗系海相烃源岩。羌塘南部发育南羌塘薄皮推覆构造,导致班公—怒江蛇绿岩、三叠系—侏罗系海相地层及侏罗纪混杂岩自北向南逆冲推覆于古近纪红层与下白垩统海相沉积岩层之上,形成三条蛇绿岩片带、大量飞来峰和厚度较大的构造片岩。中新世早期火山岩层和湖相沉积呈角度不整合覆盖逆冲断层、褶皱构造和逆冲岩席,不整合面上覆火山岩年龄为23.7~19.1Ma,指示中新世早期改则及邻区基本结束了强烈逆冲推覆构造运动。估算羌中逆冲推覆构造的推覆距离约100~115km,南羌塘逆冲推覆构造的推覆距离约82~110km;新生代早期改则逆冲推覆构造系统近南北方向逆冲推覆总距离为182~225km,对应地壳缩短率为(50.3±2.7)%。  相似文献   

3.
通过野外地质调查结合大地电磁测深综合构造解释,在休宁—歙县金多金属矿整装勘查区及邻区厘定出发育于晚侏罗世的较大规模逆冲推覆构造,其由逆冲断层、逆冲岩席、原地岩系、构造窗及伴生的牵引褶皱等组成。该逆冲推覆构造发育于"屯溪—休宁"红层盆地南缘,表现为晚元古代浅变质火山-碎屑岩系逆冲推覆于中侏罗统洪琴组碎屑岩之上。逆冲推覆构造由一系列分支逆断层组成,以前展式叠瓦状逆冲为特征,断层前缘陡立,向下变缓。逆冲推覆构造呈北东走向展布,勘查区内延伸可达40 km,推覆体面积大于600 km2。构造窗出露位置结合钻探、物探揭示,逆冲位移为2.0~8.0 km。根据逆冲断层时空配套以及岩浆活动与波及的沉积地层,判断晚侏罗世逆冲推覆构造活动时间为163.5~149.0 Ma。通过逆冲断层擦痕观察及古应力场分析,认为该期逆冲推覆构造形成于华南板块向北强烈挤压的区域动力学环境。逆冲推覆构造为成矿前构造,其与之后发生的伸展构造对岩浆的侵入及含矿热液的流通起着重要的作用,控制了整装勘查区内金、银、铅锌等中低温元素的分布与富集成矿。  相似文献   

4.
青藏高原羌塘盆地南部古近纪逆冲推覆构造系统   总被引:2,自引:0,他引:2  
吴珍汉  叶培盛  胡道功  陆露 《地质通报》2011,30(7):1009-1016
西藏羌塘地块南部古近纪发育肖茶卡-双湖逆冲推覆构造、多玛-其香错逆冲推覆构造、赛布错-扎加藏布逆冲推覆构造,构成古近纪大型逆冲推覆构造系统。沿逆冲推覆构造的前锋断层,二叠系白云岩与大理岩化灰岩、三叠系砂岩与页岩、侏罗系碎屑岩与碳酸盐岩和三叠纪—侏罗纪蛇绿岩自北向南逆冲推覆于古近纪红色砂砾岩之上,形成规模不等的构造岩片与飞来峰。羌塘盆地南部主要的逆冲断层和下伏的褶皱红层被中新世湖相沉积地层角度不整合覆盖,表明逆冲推覆构造运动自中新世以来基本停止活动。羌塘盆地南部古近纪逆冲推覆构造运动在近南北方向产生的最小位移为90km,指示新生代早期上地壳缩短率约为47%。古近纪逆冲推覆构造对羌塘盆地油气资源具有重要影响。  相似文献   

5.
羌塘盆地结构构造与油气勘探方向   总被引:4,自引:0,他引:4       下载免费PDF全文
羌塘盆地是我国陆域大型中生代海相沉积盆地,富含烃源岩,但结构构造非常复杂。结合野外观测及相关资料对地震反射剖面进行地质构造详细解释,良好地揭示了羌塘盆地结构和深部构造。羌塘盆地逆冲推覆构造延伸存在显著差别,北羌塘凹陷多格错仁逆冲推覆构造、阿木错逆冲推覆构造与南羌塘凹陷肖茶卡—双湖逆冲推覆构造、多玛—其香错逆冲推覆构造仅发育于盆地表层0~3km深度范围,北羌塘凹陷龙尾错逆冲推覆构造、羌中隆起北缘逆冲推覆构造、南羌塘凹陷赛布错—扎加藏布逆冲推覆构造、拉萨地块北缘色林错逆冲推覆构造系统自地表向深部延伸深度超过6km,羌塘盆地深部还发育中生界底部逆冲系和基底逆冲系,伴有不同规模的褶皱构造。逆冲推覆构造形成活动时代包括晚白垩世、古近纪早期和古近纪晚期,晚白垩世与古近纪早期逆冲推覆构造运动导致构造隆升的裂变径迹年龄分别为87±5~75±4Ma、64±5~46±4Ma。经过多期逆冲推覆构造改造和褶皱变形,羌塘盆地中生界海相沉积地层与烃源岩显著增厚,为新生代晚期二次生烃及油气成藏提供了非常有利的地质构造条件;北羌塘凹陷发育万安湖向斜、半岛湖背斜、东湖向斜、阿木错向斜,南羌塘凹陷发育宁日圈闭、鲁雄错背斜、诺尔玛错圈闭、协德圈闭、崩则错圈闭,羌中隆起下伏侏罗系和三叠系烃源岩,色林错下白垩统下伏古近纪湖相沉积,这些构造部位都是油气勘探的重要靶区。  相似文献   

6.
帕米尔弧东段逆冲推覆构造特征   总被引:1,自引:0,他引:1  
帕米尔弧形构造带是青藏高原碰撞挤压表现最明显的地区之一。通过构造剖面和地震剖面解释,认为帕米尔弧东段逆冲推覆构造具有分带性特点,自南西向北东方向可以划分为逆冲推覆构造的根带、中带、锋带与锋前带,相应地发育叠瓦状逆冲断层、冲断褶皱、断层相关褶皱、单斜构造等不同的构造组合。对逆冲推覆锋带中苏盖特和阿克陶生长背斜、生长地层及形成时序分别进行了研究,确定了帕米尔弧形逆冲推覆构造以前展式(背驮式)向前陆方向扩展,逆冲推覆始于上新世,并一直持续到早更新世。弧形构造东西两段逆冲推覆运动方式和地层缩短量有很大差异:西段为与挤压方向垂直的逆冲,而东段为斜冲兼顺时针走滑;西段地层缩短量大于东段。  相似文献   

7.
吴珍汉  陆露  赵珍  胡道功  张耀玲 《地质通报》2016,35(7):1056-1068
通过详细的野外观测结合地质填图资料,在聂荣变质杂岩及邻区厘定大规模逆冲推覆构造,不同时代的逆冲岩席自北—北东向南—南西逆冲推覆于上白垩统红层及下伏岩石地层之上,形成大量逆冲断层、滑脱构造、飞来峰、构造窗和褶皱构造。逆冲推覆构造运动导致侏罗纪蛇绿混杂岩、石炭系—二叠系构造层、古生界浅变质岩、变质基底之间发生拆离滑脱,在聂荣变质杂岩内部形成韧性剪切带和高角度斜冲断层。在唐古拉山口南侧形成北西—南东向土门-托纠-杂色右旋走滑断裂,走滑断裂末端转换为近东西向逆冲推覆构造。聂荣变质杂岩顶部逆冲推覆叠加滑覆,导致侏罗系混杂堆积和古生界沉积盖层向南西—西向运移86~110km,在那曲-巴尔达-班戈北形成近东西向长透镜状懂错蛇绿混杂岩逆冲岩席,沿缓倾斜断层发育向西倾斜的构造片理、摩擦镜面和近东西走向的矿物线理。裂变径迹测年表明,聂荣变质杂岩及邻区逆冲推覆及构造隆升时代主要为早白垩世晚期—晚白垩世早期(111±5~91±5Ma)、晚白垩世晚期(89±6~69±5Ma)、古新世晚期—始新世早期(55±4~44±2Ma),估算构造隆升视速率为0.10~0.69mm/a,部分断层逆冲推覆及构造隆升延续至古近纪晚期。综合各类观测资料,建立不同时期构造模式,探讨聂荣变质杂岩及邻区逆冲推覆构造演化过程及形成机理。  相似文献   

8.
青藏高原中段古近纪早期古构造演化   总被引:1,自引:0,他引:1  
青藏高原古近纪早期发育大量区域逆冲推覆构造系统, 典型实例如冈底斯逆冲断裂系、纳木错西逆冲推覆构造、伦坡拉逆冲推覆构造、唐古拉山北逆冲推覆构造、东昆仑南部左旋斜冲断裂系。古近纪逆冲推覆构造对古新世—始新世沉积盆地具有重要控制和改造作用。冈底斯古新世—始新世早期发育大量中酸性岩浆侵入和多期中酸性火山喷发, 岩石Sr/Y-Y地球化学显示为岛弧岩浆岩, 推断与古近纪早期新特提斯残留古大洋板块俯冲存在成因联系。古近纪早期新特提斯残留大洋板块俯冲向印度大陆板块俯冲的转换时代约为46-45 Ma, 转换期前逆冲推覆构造运动与新特提斯残留古大洋板块俯冲存在密切关系; 转换期后印度大陆板块俯冲导致更为强烈的逆冲推覆构造运动和挤压缩短变形, 不仅使早期很多逆冲推覆构造继续发生构造运动, 还在喜马拉雅、冈底斯、风火山、东昆仑南部形成大量新的逆冲推覆构造系统。  相似文献   

9.
库车坳陷西段的逆冲推覆距离研究   总被引:2,自引:0,他引:2       下载免费PDF全文
库车坳陷西段地区发育有巨厚膏盐层,喜马拉雅山末期构造运动使天山造山带大幅度向南挤压,造成大量盐体在库车前陆褶皱冲断带前缘被逆冲推覆至地表,地层并发生强烈的褶皱和逆冲推覆,所以在计算该区域地层向南推覆的总距离时,不仅要考虑平衡剖面技术所恢复出地层横剖面上的缩短量,另外还要考虑由于膏盐层塑性流动所造成上盘推覆体向南的滑移距离,本文综合利用平衡剖面技术和物理模拟实验方法求取了该研究区域的地层缩短量(24.5km)及上盘推覆体向南的滑移距离(3.969~14.727km),从而计算出库车坳陷西段的逆冲推覆距离为18.5~39.227km。  相似文献   

10.
鄂尔多斯盆地西缘发育南北向展布的逆冲推覆构造带,通过求其地层的缩短量和正确估计应变的分布,可以定量地揭示岩层的变形特征,从而对逆冲推覆构造形成的动力学机制做出客观的判断。由于小尺度褶皱和断层的发育,采用传统的平衡地质剖面方法计算其缩短量往往存在较大的误差,因此,采用非线性的方法--分形几何学求取逆冲推覆构造的缩短量,将剖面中某一地层界线作为二维平面中的一条复杂曲线,求其分维数D,进而计算构造变形的总缩短量。以鄂尔多斯盆地西缘北段桌子山地区AB地质剖面为例进行了应用研究。计算结果表明,桌子山AB地质剖面的缩短量为8 km,应变为22.2%,其中由小尺度褶皱和断层引起的的缩短量为1 km。  相似文献   

11.
管树巍 《地质科学》2018,(1):221-241
利用天然地震环境噪声成像研究柴达木盆地及邻区的岩石圈结构,利用工业地震剖面研究新生代构造变形的几何学与运动学特征,在此基础上讨论柴达木盆地新生代的成盆动力学过程与演化。柴达木盆地及邻区的岩石圈表现出向南和向北挠曲的特征。其中,东昆仑-可可西里地区地壳深度30~40 km 的低速层向北抬升,可与柴达木盆地内部深度15 km 左右的低速区相连接,反映了东昆仑-祁漫塔格山向柴达木盆地的逆冲推覆作用,因此在岩石圈尺度上,柴达木新生代成盆动力学过程与前陆盆地是相似的,表现为构造负荷引起的挠曲沉降。柴达木盆地新生代构造变形受控于柴西南和柴北缘两期冲断系统,柴北缘冲断系统形成于古新世-始新世路乐河-下干柴沟期,主要记录于祁连山山前、阿尔金山山前北段及冷湖和鄂博梁深层;柴西南冲断系统形成于早中新世下油砂山期以来,现今盆地南部的北西向构造带和盆地北部的冷湖和鄂博梁浅层构造都属于这期冲断系统。由于柴西南冲断系统的前锋构造已扩展至柴达木盆地北缘,并受到阿尔金山和祁连山的阻挡,缺少稳定的台盆区,因而使得柴达木盆地新生界不发育前陆盆地特有的楔状沉积结构。柴西南和柴北缘两期冲断系统的叠加,不仅使得柴达木新生代构造变形在时间和空间上呈现有次序的分布,也使得新生代盆地呈现出开启到封闭的演化格局,从而对新生界油气生成和聚集产生了重要影响。  相似文献   

12.
帕米尔东北缘地区构造变形特征与盆山结构   总被引:7,自引:0,他引:7  
帕米尔东北缘乌泊尔地区是正确认识帕米尔北缘盆山结构和构造变形特征非常关键的地区,本文利用连续电磁剖面(CEMP)资料和地震资料,并结合野外地质调查资料和钻井资料,对帕米尔东北缘乌泊尔地区的盆山结构和构造变形特征进行了研究。认为帕米尔东北缘及其以北地区的盆山结构表现为帕米尔造山带向北冲断和南天山向南冲断所形成的对冲结构;帕米尔山前为基底卷入式构造,古生界—中生界沿高角度的逆冲断层推覆到新近系和第四系之上,形成山前的古生界—中生界逆冲推覆带;北侧由受乌泊尔断裂控制的深部隐伏冲断体系和浅部的第四纪背驮盆地所构成。研究区的新生代构造变形时间开始于上新世晚期,并持续变形至今,形成了下更新统西域组(Q_1x)与下伏上新统、Q_2与Q_1和Q_(3-4)与Q_2之间的不整合。研究区最小构造缩短量为48.6 km,缩短率为48.1%。  相似文献   

13.
Three magnitude >6 earthquakes struck Qaidam, Qinghai province, China, in November 10th 2008, August 28th and 31st 2009 respectively. The Zongwulongshan fault has often been designated as the active seismogenic structure, although it is at odd with the data. Our continuous GPS station (CGPS), the Xiao Qaidam station, located in the north of the Qaidam basin, is less than 30 km to the southwest of the 2008 earthquake. This CGPS station recorded the near field co-seismic deformation. Here we analyzed the co-seismic dislocation based on the GPS time series and the rupture processes from focal mechanism for the three earthquakes. The aftershocks were relocated to constrain the spatial characteristics of the 2008 and 2009 Qaidam earthquakes. Field geological and geomorphological investigation and interpretation of satellite images show that the Xitieshan fault and Zongwulongshan fault were activated as left lateral thrust during the late Quaternary. Evidence of folding can also be identified. Integrated analyses based on our data and the regional tectonic environment show that the Xitieshan fault is the fault responsible for the 2008 Qaidam earthquake, which is a low dip angle thrust with left lateral strike slip. The Zongwulongshan fault is the seismogenic fault of the 2009 earthquakes, which is a south dipping back thrust of the northern marginal thrust system of the Qaidam basin. Folding takes a significant part of the deformation in the northern marginal thrust system of the Qaidam basin, dominating the contemporary structure style of the northern margin of the Qaidam basin and Qilianshan tectonic system. In this region, this fault and fold system dominates the earthquake activities with frequent small magnitude earthquakes.  相似文献   

14.
塔里木盆地西部的新生代断裂活动   总被引:1,自引:0,他引:1  
研究区以塔里木盆地西部的巴楚隆起为核心,包括其南侧的麦盖提斜坡和北侧的北部坳陷(阿瓦提凹陷)。这里新生代断裂异常发育。以鸟山-古董山地区为重点,通过精细的地震剖面解释,在塔里木盆地西部识别出5期新生代断裂活动,分别发生于:白垩纪末-古近纪初(ca.65Ma)、中新世末-上新世初(ca.5Ma)、上新世末-更新世中期(ca.3~1.5Ma)、更新世中-晚期(ca.1~0.1Ma)和全新世(ca.0.01Ma)。中寒武统和古近系膏盐层构成了研究区的2个主滑脱面。ca.65Ma的冲断受控于基墨里中间大陆与亚洲大陆碰撞的远程效应;ca.5Ma、ca.3~1.5Ma、ca.1~0.1Ma和ca.0.01Ma的断裂活动(包括滑脱断层、冲断层、走滑断层和正断层)均受控于印度-亚洲碰撞的远程效应。晚新生代(中新世以来)的断裂活动以脉动式冲断为特征,两次相邻脉动式冲断之间为时间不等的短暂的构造间歇期;间歇期构造平静,甚至可以形成正断层。  相似文献   

15.
THE FORMATION AND EVOLUTION OF ALTYN TAGH FAULT SYSTEM AND ITS RELATIONSHIP TO THE GROWTH OF TIBETAN PLATEAUtheNational(G19980 4 0 80 0 )andthefundofOpeningLaboratoriesofGeomechanics  相似文献   

16.
吕宝凤  杨永强  李丽 《西北地质》2010,43(4):143-151
断裂体系是具有成生联系的各项不同产状、不同等级、不同性质和不同序次的断层组合,柴达木盆地受到印度、西伯利亚和太平洋三大板块的共同影响,围绕中部刚性基底周边发育北部祁连山、南部东昆仑山及西部阿尔金山三大断裂体系,每个断裂体系都是由主要断裂及其伴生的断层相关褶皱组成三排波浪式冲断构造,低序次断层及其相关褶皱呈斜列式分布于其间,整个盆地可以看成三大断裂体系叠合的产物,其根本动力学背景是柴达木地块受到南部印度板块向北挤压、北部阿拉善地块的阻挡及东侧华北板块和西侧塔里木板块的侧滑而形成的力偶环境,结合平衡剖面分析结果提出盆地发展经历了早—中侏罗世南北向拉张、新生代多次幕式挤压并叠加东西向侧向走滑、并于第四纪形成现今的构造面貌的发展历史。  相似文献   

17.
The eastern margin of the Qaidam Basin lies in the key tectonic location connecting the Qinling, Qilian and East Kunlun orogens. The paper presents an investigation and analysis of the geologic structures of the area and LA-ICP MS zircon U-Pb dating of Paleozoic and Mesozoic magmatisms of granitoids in the basement of the eastern Qaidam Basin on the basis of 16 granitoid samples collected from the South Qilian Mountains, the Qaidam Basin basement and the East Kunlun Mountains. According to the results in this paper, the basement of the basin, from the northern margin of the Qaidam Basin to the East Kunlun Mountains, has experienced at least three periods of intrusive activities of granitoids since the Early Paleozoic, i.e. the magmatisms occurring in the Late Cambrian (493.1±4.9 Ma), the Silurian (422.9±8.0 Ma-420.4±4.6 Ma) and the Late Permian-Middle Triassic (257.8±4.0 Ma-228.8±1.5 Ma), respectively. Among them, the Late Permian - Middle Triassic granitoids form the main components of the basement of the basin. The statistics of dated zircons in this paper shows the intrusive magmatic activities in the basement of the basin have three peak ages of 244 Ma (main), 418 Ma, and 493 Ma respectively. The dating results reveal that the Early Paleozoic magmatism of granitoids mainly occurred on the northern margin of the Qaidam Basin and the southern margin of the Qilian Mountains, with only weak indications in the East Kunlun Mountains. However, the distribution of Permo-Triassic (P-T) granitoids occupied across the whole basement of the eastern Qaidam Basin from the southern margin of the Qilian Mountains to the East Kunlun Mountains. An integrated analysis of the age distribution of P-T granitoids in the Qaidam Basin and its surrounding mountains shows that the earliest P-T magmatism (293.6-270 Ma) occurred in the northwestern part of the basin and expanded eastwards and southwards, resulting in the P-T intrusive magmatism that ran through the whole basin basement. As the Cenozoic basement thrust system developed in the eastern Qaidam Basin, the nearly N-S-trending shortening and deformation in the basement of the basin tended to intensify from west to east, which went contrary to the distribution trend of N-S-trending shortening and deformation in the Cenozoic cover of the basin, reflecting that there was a transformation of shortening and thickening of Cenozoic crust between the eastern and western parts of the Qaidam Basin, i.e., the crustal shortening of eastern Qaidam was dominated by the basement deformation (triggered at the middle and lower crust), whereas that of western Qaidam was mainly by folding and thrusting of the sedimentary cover (the upper crust).  相似文献   

18.
Recent mapping and seismic survey reveal that intensive compression during the Early Cenozoic in the Qiangtang block of the central Tibetan Plateau formed an extensive complex of thrust sheets that moved relatively southward along several generally north-dipping great thrust systems. Those at the borders of the ~450 km wide block show it overrides the Lhasa block to the south and is overridden by the Hohxil-Bayanhar block to the north. The systems are mostly thin-skinned imbricate thrusts with associated folding. The thrust sheets are chiefly floored by Jurassic limestone that apparently slid over Triassic sandstone and shale, which is locally included, and ramped upward and over Paleocene-Eocene red-beds. Some central thrusts scooped deeper and carried up Paleozoic metamorphic rock, Permian carbonate and granite to form a central uplift that divides the Qiangtang block into two parts. These systems and their associated structures are unconformably overlain by little deformed Late Eocene-Oligocene volcanic rock or capped by Miocene lake beds. A thrust system in the northern part of the block, as well as one in the northern part of the adjacent Lhasa block, dip to the south and appear to be due to secondary adjustments within the thrust sheets. The relative southward displacement across this Early Cenozoic mega thrust system is in excess of 150 km in the Qiangtang block, and the average southward slip-rate of the southern Qiangtang thrusts ranged from 5.6 mm to 7.4 mm/a during the Late Eocene-Oligocene. This Early Cenozoic thrusting ended before the Early Miocene and was followed by Late Cenozoic crustal extension and strike-slip faulting within the Qiangtang block. The revelation and understanding of these thrust systems are very important for the evaluation of the petroleum resources of the region.  相似文献   

19.
鄂尔多斯北缘石合拉沟逆冲推覆构造的发现及意义   总被引:12,自引:0,他引:12  
最近在包头市幅1/25万区域地质调查工作中,在黄河南部鄂尔多斯北缘隆起带中发现了由北向南逆冲的石合拉沟推覆构造。上盘逆冲推覆体由基底浅变质的石英岩、黑云变粒岩和大理岩构成,推覆在晚石炭统太原组和中三叠统二马营组之上。野外地质关系表明逆冲推覆变形作用发生在晚侏罗世,与河套新生代断陷盆地北缘大青山逆冲推覆构造晚期逆冲推覆变形作用是同时的,逆冲推覆方向相反,构成了以现代河套盆地为中心的晚侏罗世背冲型逆冲推覆构造。该逆冲推覆构造的发现对探讨华北地台北缘中生代地壳构造变形特点和新生代河套断陷盆地基底构造性质具有重要意义。  相似文献   

20.
The Qaidam Basin, located in the northern margin of the Qinghai–Tibet Plateau, is a large Mesozoic–Cenozoic basin, and bears huge thick Cenozoic strata. The geologic events of the Indian-Eurasian plate–plate collision since ~55 Ma have been well recorded. Based on the latest progress in high-resolution stratigraphy, a technique of balanced section was applied to six pieces of northeast–southwest geologic seismic profiles in the central and eastern of the Qaidam Basin to reconstruct the crustal shortening deformation history during the Cenozoic collision. The results show that the Qaidam Basin began to shorten deformation nearly synchronous to the early collision, manifesting as a weak compression, the deformation increased significantly during the Middle and Late Eocene, and then weakened slightly and began to accelerate rapidly since the Late Miocene, especially since the Quaternary, reflecting this powerful compressional deformation and rapid uplift of the northern Tibetan Plateau around the Qaidam Basin.  相似文献   

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