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初论板内造山带 总被引：55，自引：10，他引：45
讨论了关于板内造山带含义的不同认识。指出板内造山带是一种特殊类型的造山带,而不是板缘造山带或板间造山带持续发展的结果。简要介绍分别发育在４ 个大陆的不同时代的板内造山带,总结板内造山带在区域大地构造位置、造山带构造格局、构造变形与变质作用、岩浆活动与沉积作用、造山带构造演化等方面与板缘造山带的差异。板内造山带形成于相对较老且强硬的岩石圈板块内部,造山带内部构造单元不具有平行于造山带走向分布的特征,即不具有线状构造格局,构造变形具有地台基底乃至整个地壳卷入的厚皮构造性质,同造山区域变质作用微弱,同造山岩浆活动、沉积作用和构造变形均无极性演化趋势。岩石圈拆沉作用（ｄｅｌａｍｉｎａｔｉｏｎ） 可较好地解释板内造山带的火山活动特征。尽管板块间相互作用（ 俯冲或碰撞）所产生的水平挤压应力似乎更易于阐明板内造山带的收缩变形特征;但是,板块间相互碰撞或俯冲产生的边界应力可否有效地被远程传递,尚有待进一步研究和解决。将板块间相互作用的水平应力场与岩石圈纵向物质与能量调整（ 重力、热力等） 因素作综合考虑,可能是解决板内造山带造山作用机制的有效途径 相似文献
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初论环准噶尔斑岩铜矿带的地质构造背景与形成机制 总被引：34，自引：17，他引：17
准噶尔地区构造-岩浆-成矿带具环准噶尔地块分布的特征,这一格局是准噶尔地区古生代大地构造演化的结果。哈萨克斯坦-准噶尔板块在北侧古亚洲洋与南侧南天山洋的俯冲下不断侧向增生,并形成与岩浆作用伴生的火山岩型铜铁多金属矿带、斑岩铜钼金矿带与浅成低温金矿带。哈萨克斯坦-准噶尔板块与西伯利亚板块和塔里木板块碰撞发生了强烈挤压-剪切变形,并导致准噶尔地块发生逆时针旋转,从而造成构造-岩浆-成矿带发生位移、呈环状分布于准噶尔地块周边。环准噶尔斑岩铜矿形成于俯冲成因的大陆岛弧、大洋岛弧与弧后盆地及后碰撞阶段板内4种构造背景,晚古生代是成矿的高峰时期。 相似文献
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西藏冈底斯东段南北向构造特征与成因 总被引：2，自引：0，他引：2
西藏冈底斯东段位于青藏高原冈底斯-念青唐古拉板片中段,限定于班公湖-怒江板块缝合带和雅鲁藏布江板块缝合带之间的中生代构造盆地.盆地南北向张性断裂带是板块超碰撞期活动最强烈的构造带.地震、地热和岩浆活动以及控制的线性地貌十分明显.南北向构造带的南北向延伸、东西向展布、切割深度、活动强度的规律性和差异性,充分反映了新构造活动期高原隆升过程中地壳褶缩叠覆、物质侧向滑移和弹滞应变的构造活动特点. 相似文献
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西藏冈底斯东段南北向构造特征与成因 总被引：9，自引：0，他引：9
西藏冈底斯东段位于青藏高原冈底斯－念青唐古拉板片中段，限定于班公湖－怒江板块缝合带和雅鲁藏布江板块缝合带之间的中生代构造盆地。盆地南北向张性断裂带是板块超碰撞期活动最强烈的构造带。地震、地热和岩浆活动以及控制的线性地貌十分明显。南北向构造带的南北向延伸、东西向展布、切割深度、活动强度的规律性和差异性，充分反映了新构造活动期高原隆升过程中地壳褶缩叠覆、物质侧向滑移和弹滞应变的构造活动特点。 相似文献
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提要：在大量综合亚洲地质、地球化学与地球物理资料的基础上,笔者新编了亚洲大地构造区划图,确定了划分原则,将亚洲大陆划分为六大构造域,以及67个板块（或地块）、碰撞带或增生碰撞带,并以此为基础进行了图件的编制。组成亚洲大陆的板块或地块主要形成于1800 Ma、800 Ma、 500 Ma 和400 Ma前后,上述时期即各地块形成统一结晶基底的时期。碰撞带或增生碰撞带形成时期较多,为800 Ma、397 Ma、345～260 Ma、200 Ma、135 Ma、52 Ma和23 Ma等,还有23 Ma以来形成俯冲带。对于资料比较充实的、古生代以后的板块运移、板内变形与碰撞带的形成过程进行了概略的讨论。本文还关注了在地块形成之后的板内变形。正是板内变形阶段,可能对成矿作用及其类型、过程与赋存部位产生重要的影响。 相似文献
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华北板内造山带的形成史 总被引：53，自引：7，他引：53
本文从周缘环境的演变上论述了华北古板块板内造山带的形成史:T—J_2因相邻古板块之间碰撞和陆内俯冲,导致南北边部Ew向推覆造山带的形成;J_3—K_1由西太平洋活动高潮期形成的NNE向造山带波及古板块内部;K_2—R由于滨太平洋带的弧后拉张作用,形成板内陷落带和断块山,本文强调板内次级构造单元应按古板块碰撞的不同阶段和特征予以划分和厘定。 相似文献
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闽台地球动力学及其能态结构研究 总被引：1，自引：0，他引：1
台湾地处中国大陆东南边缘是菲律宾海板块凸向亚欧大陆俯冲-碰撞异常岛弧带。福建位于台湾岛弧西侧活动地块。闽台独特的构造格架、地球动力学状态和构造应力场与地震活动之间的内在关联性,使之成为研究海陆板块俯冲-碰撞效应及其对板内地震活动影响天然地区。本文主要依据近30多年以来对福建地块的地震地质背景、地壳变形观测、构造应力场、地震活动性以及地壳-上地幔结构探测、地热场等资料,结合台湾学者详细对台湾岛弧地球动力学与强震构造等研究成果,探索海陆板块俯冲-碰撞地球动力学特征及其对板内活动地块影响,进而揭示板间-板缘-板内强震活动关联性和动力学性状的异同性。试图为本区强震预测和防震减灾对策提供新思路。 相似文献
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下扬子地区前陆变形构造格局及其动力学机制 总被引：31，自引：0，他引：31
华北板块与扬子板块于印支－早燕山期发一陆－陆碰撞时,使造山带南部的下扬子地区成为前陆变形带。下扬子前陆变形带上,大致以长江为界,北部的逆冲推覆构造系统为向南运动,南部的逆冲推覆构造系统为向北运动,总体呈两套对冲的逆冲推覆构造系统。长江以北前陆变形的动力来自华北与扬子板块沿大别－胶南造山带的碰撞,长江以南前陆变形的动力来自沿江南隆起带的板内造山。 相似文献
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北天山东段康古尔塔格碰撞构造 总被引：1，自引：0，他引：1
塔里木板块和准噶尔板块间的康古尔塔格带是发育在北天山东部地区的晚古生代碰撞构造，本文对该碰撞造山带在形成和地质演化过程中的构造变动、岩浆作用和沉积作用做了较详细的论述，并对该碰撞构造的碰撞时代、碰撞单元和碰撞标志进行了探讨，尝试性提出了其碰撞的４个阶段。 相似文献
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现今全球构造特征及其动力学解释 总被引：39，自引：1，他引：39
构造地质学、大地构造学和全球构造学是三个尺度的构造学研究领域,它们平行交叉而且互有扬弃。全球构造学可分为历史的和现今的两个分支。岩石圈板片和板条构造、板舌构造、洋脊构造以及大陆岩石圈多元组合板的多重滑脱构造和多层剪切构造网络等是现今岩石圈板的基本构造形态。全球级现今岩石圈构造主要表现为三大构造系统:环太平洋深消减带板舌构造系、大洋增生带洋脊构造系和大陆碰撞造山构造系,三者在球坐标系内表现出构造形态、物理场背景和动力学状态等多方面半球级的反对称关系(南/北、0°/180°),各构造系统内部还表现了普遍的东西反对称。论其动力学解释,岩石圈向西和地幔向东相对漂移的定向性显示了地球自转变化的导向作用,决定了经向构造两侧的多级反对称;地震层析探测到的地幔结构显示的热心南偏和质心北偏可能是南北反对称的动力基础;上地幔分层结构及“软层”物质在构造引张条件下形成的热涌有可能解释地表的视对流现象,有助于说明构造变动的跳位和变格以及板条和反对称运动机制。 相似文献
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《地学前缘(英文版)》2023,14(3):101553
Eight lines of evidence indicate that the Orosirian Period in mid-Paleoproterozoic time was characterized by plate tectonics: ophiolites, low T/P metamorphism including eclogites, passive margin formation, tall mountains, paleomagnetic constraints, ore deposits, abundant S-type granites, and seismic images of paleo-subduction zones. This plate tectonic episode occurred about 1 billion years earlier than the present plate tectonic episode began in Neoproterozoic time. The two plate tectonic episodes bracket the ‘Boring Billion’, which may have been a protracted single lid tectonic episode that began when the supercontinent Nuna or Columbia formed. Recognition of multiple lines of evidence for Orosirian plate tectonics demonstrates that Earth’s tectonic style can be reconstructed with some confidence back to at least Early Paleoproterozoic time, and thus the absence of compelling evidence for Mesoproterozoic plate tectonics is not obvious due to poor preservation. A tectono-magmatic lull ～2.3 Ga suggests an earlier episode of single lid tectonics. Evidence for two episodes of plate tectonics and two episodes of single lid tectonics indicates that Earth switched between single lid and plate tectonics multiple times during the last 2.4 Ga. 相似文献
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论中国大陆复杂和混杂的碰撞带构造 总被引：10，自引：0，他引：10
中国大陆碰撞带是以结构复杂、形成过程复杂和物质成分趋于混杂为主要特征的。在构造特征上 ,表现为由构造岩片和混杂岩带所组成 ,形成扇状褶皱和对冲型逆掩断层。在剖面上常形成楔状(鳄鱼式 )构造 ,在平面上可构成嵌入构造 ,它们其实是两个板块在碰撞过程中互相挤压、缩短与穿插的、一个统一的三维共轭剪切断裂系统中的不同表现形式。绝大多数中国大陆碰撞带都不是一次形成的 ,而是经历了多期次、活动性质各不相同的、复杂的形成过程。为了进一步提高碰撞带的研究水平 ,应该把碰撞带及其两侧的板块当作一个整体来进行综合研究 ,应该大力加强碰撞带周邻板块的沉积古地理、生物古地理、古地磁学、地球化学和构造变形、变位资料的系统研究。碰撞作用时期是元素、岩石和构造单元趋于混杂的时期 ,而不是有利于元素、物质的分异和富集。碰撞带的主碰撞期形成的矿床是十分有限的。笔者推测有 4种类型的矿床可能将成为西部古碰撞带地区找矿的主要目标。 相似文献
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侏罗纪以来,太平洋板块与欧亚板块俯冲碰撞,促成了中国东部以NNE-NE向断裂为主体的断裂构造格局。从地震面波层析成像反演资料及东北和华北地质剖面得知,该地区应属东亚巨型宽裂谷体系的东部地区,系亚幔柱活动所致。全区P波速度、岩石圈不连续和减薄转型、软流圈物质呈蘑菇云状上升以及大火成岩省等特征证明中国东部中、新生代为亚幔柱构造控制成矿成藏,从而证实板块构造与幔柱构造相辅相成的关系。幔柱构造可划分3级,金属矿床常受幔枝构造的控制,多成群成带分布。由于成矿物质来自深部地核或软流圈,金属元素呈垂直分带的规律成为"攻深找盲"的理论依据;而油气田深部常受深部热源影响,若有海相烃源层分布,是寻找"无机"和海相油气田的主攻目标。 相似文献
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In the fifteen years since the importance of collisional plateaus with thickened continental crust began to be recognized as one of the inevitable consequences of the processes of plate tectonics, rapid progress in their understanding has come from studies of the world's only active terminal collision zones in the Himalayan-Tibetan and Turkish-Iranian plateaus.Ancient collisional plateaus are being recognized throughout the geological record (back to 3.8 Ga) from the occurrence of extensive areas (typically > 500,000 km2) of 8 kbar metamorphism in granulite facies or from the occurrence of extensive areas of higher level minimum-melt composition granite rocks whose isotopic signatures indicate reactivation of existing continental crust rather than addition of new crust from the mantle at the time of collision. Recognition of strike-slip faulting in the ancient collisional plateau areas indicates that “tectonic escape” may have been as important in the past as it is today.Earth may not be the only planet on which collisional plateaus are important. The highlands of Venus (approximately 7% of the surface with elevations over 1.5 km above mean planetary radius) can only exist as a result of crustal thickening, and not as a product of lithospheric thinning. Most of these highlands can be explained by models involving volcanic construction. However, the highest peaks, including Maxwell Montes, the highest mapped area of Venus rising over 10 km above mean planetary radius, require much greater crustal thickening to support them than can reasonably be explained by a volcanic mechanism. Geological features of Maxwell Montes inferred from radar images suggest some analogy between Maxwell Montes and the Tibetan plateau.It is somewhat paradoxical that extensional tectonics are commonly associated with continental collision, and that collision-related rifts may be the only sites where the uppermost layers of a collision-thickened crust are preserved from erosion. Extensional stress fields are generated during continental collision, primarily in areas associated with strike-slip faulting and “tectonic escape”. Additional extensional stresses are gravitationally generated associated with the topography and thickened crust in a collision zone. Tectonically thickened crust is particularly susceptible to rifting as its lithosphere is weak as a result of heating associated with magmatism. This lithosphere is also compositionally weak because of the relatively thick crust, dominated by a weak quartz rheology, and thin mantle lithosphere, dominated by a strong olivine rheology, in comparison with a lithosphere with a more normal crustal thickness. Thus, the common association of rifts and collision zones may be a consequence of both stresses generated during collision and modification of the lithosphere by collision. 相似文献
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V. N. Patrikeev 《Geotectonics》2013,47(5):362-375
The style and age of deformations of the sedimentary cover and basaltic basement in the northwestern basin of the Pacific Ocean were studied based on seismic data coordinated with the results of deep-water drilling. The deformations are widespread not only on the oceanic slope of the trench as a plate boundary, but also within the plate especially close to the large Hokkaido, Tuscarora, and Seismikov fracture zones and the Hokkaido Swell. The most intense deformation took place at the Pliocene-Quaternary boundary. Abundant diapirs related to the plastic serpentinite layer at base of the crust indicate that gravity tectonics primarily develops here. 相似文献
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板块构造理论是地学研究的一次革命,它推动了当前地球科学的发展。但是用刚性板块运动学的理论不能解释大陆内部复杂的构造形变作用和强烈的地震活动,大陆构造理论是在板块构造的基础上加以补充和发展,本文简要地介绍大陆构造研究的要点,特别是大陆构造与板内地震活动的关系。我国是一个以大陆为主体的多震国家,板内地震活动应结合岩石圈结构、块体运动学和流变学进行研究。 相似文献
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渤海湾盆地是一个中、新生代盆地,位于华北克拉通的东部地块上,是华北克拉通破坏的中心区域。渤海湾盆地的结构、构造记录了华北克拉通破坏的构造过程。文章综合10a来据三维地震资料揭示的渤海湾盆地构造,和20a来渤海湾盆地周边华北克拉通区域中、新生代构造和地球化学研究成果,系统提出华北克拉通破坏期间,渤海湾盆地深、浅部的构造机制分别为:中生代浅部构造机制是挤出构造成因,深部构造机制为局部有限的拆沉+底侵模式;新生代构造机制是北西向壳内伸展机制,与印度和欧亚板块碰撞激发的软流圈的东扩远程效应和太平洋俯冲带的跃迁式东撤的联合效应——区域性"西进东退"的深部机制有关。 相似文献
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To better understand how active deformation localizes within a continental plate in response to extensional and transtensional tectonics, a combined analysis of high-quality gravity (Bouguer anomaly) and seismicity data is presented consisting of about 35000 earthquakes recorded in the Baikal Rift Zone. This approach allows imaging of deformation patterns from the surface down to the Moho. A comparison is made with heat flow variations in order to assess the importance of lithospheric rheology in the style of extensional deformation. Three different rift sectors can be identified. The southwestern rift sector is characterized by strong gravity and topography contrasts marked by two major crustal faults and diffuse seismicity. Heat flow shows locally elevated values, correlated with recent volcanism and negative seismic P-velocity anomalies. Based on earthquake fault plane solutions and on previous stress field inversions, it is proposed that strain decoupling may occur in this area in response to wrench-compressional stress regime imposed by the India–Asia collision. The central sector is characterized by two major seismic belts; the southernmost one corresponds to a single, steeply dipping fault accommodating oblique extension; in the centre of lake Baikal, a second seismic belt is associated with several dip-slip faults and subcrustal thinning at the rift axis in response to orthogonal extension. The northern rift sector is characterized by a wide, low Bouguer anomaly which corresponds to a broad, high topographic dome and seismic belts and swarms. This topography can be explained by lithospheric buoyancy forces possibly linked to anomalous upper mantle. At a more detailed scale, no clear correlation appears between the surficial fault pattern and the gravity signal. As in other continental rifts, it appears that the lithospheric rheology influences extensional basins morphology. However, in the Baikal rift, the inherited structural fabric combined with stress field variations results in oblique rifting tectonics which seem to control the geometry of southern and northeastern rift basins. 相似文献