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A large-scale pop-up structure occurs at the front of the northern Dabashan thrust belt (NDTB),bound by the NNE-dipping Chengkou fault to the south,and the SSW-dipping Gaoqiao fault to the north.The pop-up structure shows different features along its strike as a direct reflection of the intensity of tectonic activity.To the northwest,the structure is characterized by a two-directional thrust system forming a positive flower-like structure.In contrast,the southeastern part is composed of the vertical Chengkou fault and a series of N-directed backthrusts.showing a semi-flower-like structure. We present results from Ar-Ar dating of syntectonic microthermal nietamorphic sericite which show that the Chengkou fault experienced intense deformation during the mid-Mesozoic Yanshanian epoch(about 143.3 Ma),causing rapid uplift and thrusting of the northern Dabashan thrust belt.During the propagation of this thrust,a series of backthrusts formed because of the obstruction from the frontier of Dabashan thrust belt,leading to the development of the pop-up structure. 相似文献
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在北大巴山推覆构造带前缘,北—北东倾斜的城口断裂和南—南西倾斜的高桥断裂形成一背冲式逆冲推覆体系,以两断层为界,其间为一巨型冲起构造。该冲起构造因边界断裂的产状特征、活动强度沿走向的差异,而表现出明显的分段性:其北西段为双向逆冲的"正花状"结构;而南东段为反向逆冲为主的"半花状"结构。同构造低温变质绢云母40Ar-39Ar年龄显示,城口断裂在燕山期(约143.3Ma)存在一次强烈的构造活动,导致北大巴构造带进一步逆冲扩展和强烈隆升。在逆冲-推覆向前扩展过程中,受锋缘外侧阻抗的影响,沿前缘部位形成一系列反向逆冲断层,从而形成巨型冲起构造。 相似文献
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塔里木盆地古生代重要演化阶段的古构造格局与古地理演化 总被引：14，自引：4，他引：10
塔里木盆地在古生代经历了中-晚奥陶世、晚奥陶世末、中泥盆世末等多个重要的盆地变革期,形成了多个重要的不整合,盆地构造古地理发生了重要的变化。中、晚奥陶世盆地的变革形成了由巴楚古斜坡-塔中隆起-和田河隆起构成的大型古隆起带、相对沉降的北部坳陷带以及由于挤压挠曲沉降形成的塘古孜巴斯坳陷带。中部古隆起带制约着晚奥陶世东窄西宽的弧立碳酸盐岩台地体系的发育,而开始形成于震旦纪的满加尔拗拉槽及东南侧的塘古孜巴斯坳陷接受了巨厚的中、晚奥陶世重力流沉积。奥陶纪末的盆地变革形成了北东东向展布的西南-东南缘和西北缘的强烈隆起带,总体的古构造地貌控制着早志留世北东东向展布的滨浅海陆源碎屑盆地的沉积格局。中泥盆纪世末期的盆地强烈隆升并遭受了夷平化的剥蚀作用,形成了大范围分布的角度不整合面,并以塔北隆起和塔东隆起的强烈抬升为显著特征。盆地古构造地貌从东低西高转为东高、西低,制约着晚泥盆和早石炭世由东向西南方向从滨岸到浅海的古地理分布。中、晚奥陶世主要不整合及其剥蚀量的分布反映出北昆仑向北碰撞和挤入是造成盆地南缘、东南缘及盆内隆起的主要原因。南天山洋的俯冲、碰撞在奥陶世末至早志留世已对盆地西北缘产生影响,导致塔北英买力隆起的抬升和遭受剥蚀。 相似文献
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Constantino Mpodozis Csar Arriagada Matilde Basso Pierrick Roperch Peter Cobbold Martin Reich 《Tectonophysics》2005,399(1-4):125
The Salar de Atacama basin, the largest “pre-Andean” basin in Northern Chile, was formed in the early Late Cretaceous as a consequence of the tectonic closure and inversion of the Jurassic–Early Cretaceous Tarapacá back arc basin. Inversion led to uplift of the Cordillera de Domeyko (CD), a thick-skinned basement range bounded by a system of reverse faults and blind thrusts with alternating vergence along strike. The almost 6000-m-thick, upper Cretaceous to lower Paleocene sequences (Purilactis Group) infilling the Salar de Atacama basin reflects rapid local subsidence to the east of the CD. Its oldest outcropping unit (Tonel Formation) comprises more than 1000 m of continental red sandstones and evaporites, which began to accumulate as syntectonic growth strata during the initial stages of CD uplift. Tonel strata are capped by almost 3000 m of sandstones and conglomerates of western provenance, representing the sedimentary response to renewed pulses of tectonic shortening, which were deposited in alluvial fan, fluvial and eolian settings together with minor lacustrine mudstone (Purilactis Formation). These are covered by 500 m of coarse, proximal alluvial fan conglomerates (Barros Arana Formation). The top of the Purilactis Group consists of Maastrichtian-Danian alkaline lava and minor welded tuffs and red beds (Cerro Totola Formation: 70–64 Ma K/Ar) deposited during an interval of tectonic quiescence when the El Molino–Yacoraite Late Cretaceous sea covered large tracts of the nearby Altiplano-Puna domain. Limestones interbedded with the Totola volcanics indicate that this marine incursion advanced westwards to reach the eastern CD slope. CD shortening in the Late Cretaceous was accompanied by volcanism and continental sedimentation in fault bounded basins associated to strike slip along the north Chilean magmatic arc to the west of the CD domain, indicating that oblique plate convergence prevailed during the Late Cretaceous. Oblique convergence seems to have been resolved into a highly partitioned strain system where margin-parallel displacements along the thermally weakened arc coexisted with margin-orthogonal shortening associated with syntectonic sedimentation in the Salar de Atacama basin. A regionally important Early Paleocene compressional event is echoed, in the Salar de Atacama basin by a, distinctive, angular unconformity which separates Paleocene continental sediments from Purilactis Group strata. The basin also records the Eocene–Early Oligocene Incaic transpressional episode, which produced, renewed uplift in the Cordillera de Domeyko and triggered the accumulation of a thick blanket of syntectonic gravels (Loma Amarilla Formation). 相似文献
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中国喜马拉雅构造运动的陆内变形特征与油气矿藏富集 总被引：12，自引：0，他引：12
在前人研究的基础上,结合近年来在油气勘探中不断积累的地质资料和地质认识,提出了中国喜马拉雅构造运动的陆内变形特征及其分布规律受控于小型克拉通板块拼贴的基底结构和印/欧碰撞与太平洋板块俯冲所主导的双重控制因素;喜马拉雅构造运动的发育特征主要表现为三种动力学机制:青藏高原隆升、盆地与造山带体制和东部拉张活动。喜马拉雅构造运动的大地构造格局及其构造变形分布规律集中体现为4个构造域:青藏高原隆升区、环青藏高原盆山体系、稳定区和环西太平洋裂谷活动区。我国沉积盆地在喜马拉雅构造运动中的构造特征分为三种类型:(1)东部渤海湾、松辽等盆地受拉张构造环境控制的裂谷沉降;(2)中部四川、鄂尔多斯等盆地受青藏高原的向东推挤、盆缘冲断、盆内抬升剥蚀;(3)西部的塔里木、准噶尔、柴达木等盆地受青藏高原的向北推挤、冲断挠曲沉降,表现为克拉通单边或双边的压缩挠曲沉降与克拉通内部的冲断隆升沉降等多种盆山耦合形式。喜马拉雅构造运动控制着中国油气晚期定位与富集成藏,主要体现在:盆地的沉积与成藏,形成新生界自生自储的含油气盆地和油气藏;圈闭形成与油气运聚成藏;早期油气藏的调整和再分配;油气藏的破坏。 相似文献
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塔里木盆地断裂构造分期差异活动及其变形机理 总被引：9，自引：3，他引：6
本文的目的是探讨塔里木盆地断裂构造分期差异活动过程及其变形机理.在地震剖面解释、钻井资料和地质资料综合分析的基础上,通过编制塔里木盆地不同时期断裂系统图,提出控制塔里木盆地断裂构造形成和演化主要构造活动期次为:加里东早期、加里东中期、加里东晚期-海西早期、海西晚期、印支期、燕山期和喜马拉雅期.加里东早期断裂活动受伸展环境制约,沿先存基底断裂带形成张性正断层.加里东中期、加里东晚期-海西早期断裂活动以逆冲作用为主,在塔东、塔中、塘古巴斯、巴楚和麦盖提地区最为发育.海西晚期断裂活动也是以逆冲作用为特征,并从早期断裂强烈活动的塔中、塘古巴斯、玛东等地区,迁移到塔北隆起和东部地区.印支、燕山和喜马拉雅期,前陆地区断裂构造发育,形成叠瓦冲断带、褶皱-冲断带、双重构造、盐相关构造等;但在盆内稳定区,断裂构造不发育,活动性弱.古生代断裂构造发育分布的控制机理,主要与区域大地构造环境的变化和构造转换、先存基底断裂带、大型区域性不整合、滑脱带等要素密切相关.区域大地构造环境的变化和构造转换主要受控于塔里木周缘洋盆的伸展裂解、俯冲消减和洋盆闭合的时限和强度.先存基底断裂带或基底构造软弱带往往控制着后期断裂的发育位置和展布方向.大型区域性不整合和滑脱带控制着断裂构造的发育和分布层位.中、新生代断裂构造发育分布的控制机理,与区域大地构造环境及其构造转换、区域构造位置有关.中、新生代塔里木断裂构造主要分为三种环境,即前陆构造环境、盆内稳定区构造环境和隆升剥蚀区构造环境.盆内稳定区断裂构造不发育,活动性较弱.中、新生代断裂构造主体发育在前陆构造环境中,主要受控于周缘造山带强烈隆升、挤压冲断、走滑-逆冲或逆冲-走滑作用,同时与喜马拉雅晚期盆-山耦合作用及滑脱层的发育有关. 相似文献
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印度-亚洲碰撞：从挤压到走滑的构造转换 总被引：10，自引：0，他引：10
印度-亚洲板块碰撞导致喜马拉雅山脉的崛起、青藏高原的生长、两倍于正常地壳厚度的巨厚陆壳体,以及大量青藏高原腹地的物质沿着大型走滑断裂朝东、东南、西的方向逃逸。印度-亚洲碰撞如何造成板块汇聚边界由挤压到走滑的构造转换对认识大陆岩石圈的变形机制具有重要意义。本文通过总结喜马拉雅造山带及青藏东南缘~55Ma以来的构造、变质、岩浆记录,发现高喜马拉雅的挤出起始于始新世加厚的喜马拉雅造山带中—下地壳的部分熔融,受控于渐新世以来同期发育的向南逆冲和平行造山带的韧性伸展,并建立了高喜马拉雅"三维挤出"构造模式。晚始新世以来,羌塘地块和拉萨地块的物质通过"岩石圈横弯褶皱和壳内解耦"的运动学机制,围绕东构造结发生顺时针旋转并向青藏高原东南缘逃逸。结合东南亚板块重建的资料,我们认为:印度-亚洲的"陆-陆碰撞"到印度洋板块-亚洲东南大陆的"洋-陆俯冲"的转换是导致从印度-亚洲主碰撞带的挤压到青藏东南缘走滑转换的根本原因。 相似文献
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Shallow frontal deformation related to active continental subduction: structure and recent stresses in the westernmost Betic Cordillera 
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下载免费PDF全文 Lourdes González‐Castillo Jesús Galindo‐Zaldívar Antonio Pedrera Francisco José Martínez‐Moreno Patricia Ruano 《地学学报》2015,27(2):114-121
The westernmost Betic Cordillera front is located along the arcuate alpine belt formed by the interaction of the Eurasian‐African plate boundary and the Alboran continental domain in between. Although classical geological data suggest that the western Cordillera front is inactive, recent GPS data show a westward–north‐westward motion of up to 3.4 mm a?1 with respect to the foreland. In addition, the increasing thickness of Guadalquivir sedimentary infill towards the Cordillera, and the rectilinear character of the front formed by soft sediments, suggest that the Cordillera is still active. Large ENE–WSW‐oriented open folds detected in the field, seismic reflection profiles and new audiomagnetotellurics data are consistent with active deformation. Fracture analysis in Quaternary deposits evidences recent NW–SE horizontal compression. The GPS motion and maximum stress orientation may be due to north‐westward tectonic collision of the westernmost Betic Cordillera, accommodated at depth by active continental subduction of the Iberian lithosphere. 相似文献
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滇西新生代兰坪盆地和剑川盆地分别位于哀牢山–红河断裂带两侧,青藏高原东构造结内,其沉积过程和构造变形对青藏高原东南缘的构造演化有重要的启示意义。通过对这两个盆地古近纪沉积和构造过程的研究,我们发现兰坪盆地和剑川盆地及邻区的构造变形分为三期:始新世早期的强烈挤压变形、始新世中晚期的伸展变形、渐新世的走滑变形。始新世早期的挤压变形主要表现为兰坪地区的褶皱–冲断系统、哀牢山-红河断裂的逆冲活动和剑川盆地的宽缓褶皱。沉积方面,古新统勐野井组(E_1m)较为稳定的细粒滨湖相沉积转变为始新统宝相寺组(E_2b)较粗的具有前陆盆地性质的河流相沉积,特别是宝相寺组底部发育的一套快速堆积的磨拉石建造,可能是对始新世强烈挤压环境下的沉积响应。始新世中晚期伸展变形体现在盆地的构造环境由早期的挤压环境变为伸展环境和该时期大量富钾岩体和岩脉的侵入,沉积学上,下始新统宝相寺组的河流相转变为中始新统金丝厂组(E_2j)具有快速堆积磨拉石特征的曲流河沉积,极可能是对构造体制变革的沉积响应。渐新世的走滑变形则体现在渐新统的缺失和哀牢山–红河断裂的早期左行走滑。因此,我们认为剑川–兰坪地区在始新世中期和渐新世均发生了显著的运动学转换,这一认识也得到了始新世中期兰坪和剑川盆地物源明显变化的支持。结合青藏高原东南部始新世中晚期岩浆的活动,渐新世大型剪切带(崇山剪切带、高黎贡剪切带)的强烈走滑和保山块体的旋转,我们推测青藏高原东南缘古近纪的构造演化为古新世-始新世早期的挤压、始新世中晚期的伸展、渐新世的转换压缩。 相似文献
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以构造动力学演化为主线,从拉张与挤压的辩证关系出发,提出了川渝地区构造动力学演化经历了挤压-区域拉张-陆隆伸展-再挤压的构造动力学演化过程;川渝地区在T3-J2期间为盆岭耦合构造格局,在当时山岭与盆地之间过渡的斜坡带前缘(大致相当于理县至都江堰地域),出现印支、燕山期滑覆构造,表现为山岭斜坡前缘逆冲叠瓦状断层与紧闭甚至倒转、平卧褶皱的出现;J3以来,构造动力学背景由伸展转变为挤压,形成基底卷入的厚皮构造,龙门山迅速崛起,四川盆地最终定型,形成现今见到的松潘甘孜高原-龙门山-四川盆地构成的盆山耦合构造格局。 相似文献
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Zhengle Chen Zongxiu Wang Fengbin Han Wengao Zhang Qing Zhang Zhenju Zhou 《International Geology Review》2018,60(8):1019-1037
The Mesozoic to Cenozoic mountain uplift, exhumation, and deformation of the SW Tianshan Mountains (Kyrgyzstan and Northwest China) offer an important window to understand the intra-continental rejuvenation mechanism of the Central Asian Orogenic Belt (CAOB), as response to the far-field effects of the India-Asia collision. This article presents new observation and data for the planation surface and sedimentation and deformation features of the regional intermountain basins to rebuild the orogenic history in Mesozoic to Cenozoic. Three planation surfaces were recognized by field observation, showing that the mountain may have experienced lengthy erosion since the end Cretaceous, and a continuous planation surface may have formed at the Eocene to Oligocene. The filling sequences and deformation character revealed that the orogenic disintegrate and intermountain basin formation likely began in the end of Oligocene. Subsequently, the uniform planation surface in Western Tianshan may have begun to disintegrate, leading to the basin-and-range landform formation. Folds and nappes in the Cenozoic basins, large-scale thrusting of Palaeozoic rocks over Cenozoic sediments at the basin margin associated with the rapid mountain uplift may have occurred at the end of Early Pleistocene, suggesting a tectonic inversion. The Mesozoic–Cenozoic Tianshan uplift and deformation were likely induced by the collision/accretion along the southern margin of Eurasia. Both the northward propagation of the Parmir syntaxis to the SW Tianshan and the oblique dextral faulting of the Talas–Fergana fault have likely played an important role on the formation and deformation of the Cenozoic basins in the SW Tianshan. 相似文献
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20世纪60年代提出的"威尔逊旋回"以关闭洋盆两侧板块的碰撞作为板块运动旋回的终结,然而板块构造学说"登陆"20多年来的实践说明这种认识是不全面的。大陆弥散而宽广的陆内变形说明洋盆闭合两侧板块的碰撞并未终止板内构造作用。古亚洲大陆形成后中国东部中—新生代广泛发育的板内构造变形、岩浆活动、克拉通内盆地的形成都和古亚洲大陆南、北,印度洋和北冰洋洋脊的持续扩张、西太平洋和菲律宾洋壳的俯冲相关。本文拟厘清中国东部中—新生代大陆构造形成与演化的重大事件、构造性质、形成背景及其时空展布:(1)晚海西—印支期古特提斯洋关闭陆块拼合碰撞古亚洲大陆雏形形成;(2)晚侏罗—早白垩世蒙古—鄂霍茨克海闭合,陆-陆碰撞古亚洲大陆形成,挤压逆冲推覆构造在陆内变形中形成高潮,西太平洋伊佐奈岐洋壳板块的斜俯冲叠加了自东而西的影响;(3)早白垩世晚期—古近纪加厚地壳-岩石圈减薄、转型,陆内伸展变形达到高潮,大陆克拉通泛盆地、准平原化;(4)始新世晚期—早中新世(40~23 Ma)太平洋板块运动转向对东亚大陆NWW向的挤压和印度洋脊扩张印—澳板块对古亚洲南部陆-陆碰撞挤压的叠加,形成中国东部新生的构造地貌;(5)中-上新世—早更新世受东亚—西太平洋巨型裂谷系和印度洋中脊扩张的叠加影响,中国东部岩石圈地幔隆升、地壳减薄,陆缘、陆内伸展变形相继形成边缘海、岛弧、裂谷型盆地和剥蚀高原地貌;(6)早更新世晚期(0.9~0.8 Ma)—晚更新世末(0.01 Ma)中国东部大陆构造地貌基本形成。 相似文献
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A.Encinas A.Folguera R.Riffo P.Molina L.Fernández Paz V.D.Litvak D.A.Colwyn V.A.Valencia M.Carrasco 《地学前缘(英文版)》2019,10(3):1139-1165
The Central Patagonian Andes is a particular segment of the Andean Cordillera that has been subjected to the subduction of two spreading ridges during Eocene and Neogene times. In order to understand the Cenozoic geologic evolution of the Central Patagonian Andes, we carried out geochronologic(U-Pb and40Ar/39Ar), provenance, stratigraphic, sedimentologic, and geochemical studies on the sedimentary and volcanic Cenozoic deposits that crop out in the Meseta Guadal and Chile Chico areas(～47°S). Our data indicate the presence of a nearly complete Cenozoic record, which refutes previous interpretations of a hiatus during the middle Eocene-late Oligocene in the Central Patagonian Andes. Our study suggests that the fluvial strata of the Ligorio Marquez Formation and the flood basalts of the Basaltos Inferiores de la Meseta Chile Chico Formation were deposited in an extensional setting related to the subduction of the Aluk-Farallon spreading ridge during the late Paleocene-Eocene. Geochemical data on volcanic rocks interbedded with fluvial strata of the San Jose Formation suggest that this unit was deposited in an extensional setting during the middle Eocene to late Oligocene. Progressive crustal thinning allowed the transgression of marine waters of Atlantic origin and deposition of the upper Oligocene-lower Miocene Guadal Formation. The fluvial synorogenic strata of the Santa Cruz Formation were deposited as a consequence of an important phase of compressive deformation and Andean uplift during the early-middle Miocene. Finally, alkali flood basalts of the late middle to late Miocene Basaltos Superiores de la Meseta Chile Chico Formation were extruded in the area in response to the suduction of the Chile Ridge under an extensional regime. Our studies indicate that the tectonic evolution of the Central Patagonian Andes is similar to that of the North Patagonian Andes and appears to differ from that of the Southern Patagonian Andes, which is thought to have been the subject of continuous compressive deformation since the late Early Cretaceous. 相似文献
16.
《International Geology Review》2012,54(8):876-906
The synorogenic basins of central Cuba formed in a collision-related system. A tectono-stratigraphic analysis of these basins allows us to distinguish different structural styles along the Central Cuban Orogenic Belt. We recognize three distinct structural domains: (1) the Escambray Metamorphic Complex, (2) the Axial Zone, and (3) the Northern Deformation Belt. The structural evolution of the Escambray Metamorphic Complex includes a latest Cretaceous compressional phase followed by a Palaeogene extensional phase. Contraction created an antiformal stack in a subduction environment, and extension produced exhumation in an intra-arc setting. The Axial Zone was strongly deformed and shortened from the latest Cretaceous to Eocene. Compression occurred in an initial phase and subsequent transpressive deformation took place in the middle Eocene. The Northern Deformation Belt consists of a thin-skinned thrust fault system formed during the Palaeocene to middle Eocene; folding and faulting occurred in a piggyback sequence with tectonic transport towards the NNE. In the Central Cuban Orogenic Belt, some major SW–NE structures are coeval with the Cuban NW–SE striking folds and thrusts, and form tectonic corridors and/or transfer faults that facilitated strain-partitioning regime attending the collision. The shortening direction rotated clockwise during deformation from SSW–NNE to WSW–ENE. The synchronicity of compression in the north with extension in the south is consistent with the opening of the Yucatan Basin; the evolution from compression–extension to transpression is in keeping with the increase in obliquity in the collision between the Caribbean and North American plates. 相似文献
17.
鄂尔多斯盆地渭北隆起岐山－麟游地区中新生代构造热演化及地质响应——来自裂变径迹分析的证据 总被引：1，自引：0，他引：1
本文通过对渭北隆起西南缘岐山-麟游地区构造变形特征进行研究,结合磷灰石、锆石裂变径迹测试分析及热史模拟,探讨了研究区中新生代构造热演化过程及地质响应。结果表明,燕山运动对研究区影响最大,使得研究区发生大规模构造变形及抬升,研究区中生代以来至少包括三次构造抬升:晚侏罗-早白垩世早期(138~128Ma)、早白垩世末以来,主要是晚白垩世(86~69Ma)和始新世(50~40Ma)。AFT年龄的空间分布暗示了研究区抬升冷却具有南早北晚、后期整体抬升的特点。热史模拟结果表明研究区南部在158Ma达到最大古地温,158~130Ma,样品快速抬升至部分退火带,130~40Ma为缓慢抬升,40Ma以来抬升速率明显加快。研究区中新生代构造热演化过程与相邻构造单元的相互作用具有密切的联系,晚侏罗世构造抬升与秦-祁造山带此时进入强烈多旋回陆内造山过程相对应,早白垩世稳定沉降期是鄂尔多斯盆地油气成熟的关键时期,晚白垩世以来的构造抬升与秦岭造山带抬升具有一致性,始新世以来的快速隆升,与渭河盆地北缘翘倾作用有关。 相似文献
18.
南大巴山前陆冲断带构造样式及变形机制分析 总被引：35，自引：9，他引：26
大巴山构造带位于秦岭造山带和四川盆地的过渡部位,形成于印支-燕山期,定型于喜山期。按照构造变形样式及其组合特征,从北东向南西可依次划分为北大巴山逆冲推覆构造带、南大巴山前陆褶皱-冲断带(又包括叠瓦断层带、断层-褶皱带和滑脱褶皱带等3个亚带)和四川盆地东北部低缓构造区等3个构造带(区)。南大巴山冲断带地表构造以类侏罗山式褶皱为显著特征,主要发育叠瓦断层系、断层相关褶皱、被动顶板双重构造、反冲断层系和冲起构造等变形样式。北东-南西向挤压应力和滑脱层是控制南大巴山及其前缘构造变形的主要因素,结合区域地质研究成果,建立了南大巴山及其前缘地区依次从震旦系-下寒武统-志留系-中下三叠统逐渐抬高的多层次滑脱前展模式。 相似文献
19.
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