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1.
Apatite fission-track (AFT) thermochronological modeling as a diagnostic tool for periods of stability (peneplanation) and tectonic activity (orogeny) has been broadly used in tectonic studies of Central Asia in recent years. We discuss more than 100 AFT ages of samples from the Kyrgyz Tien Shan and Altai and compare them with AFT data from northern Kazakhstan. Geological, geomorphological, and AFT data indicate intense activity in the Late Cenozoic Eurasian continental interior. The impact from the India-Eurasia collision on the northern Tien Shan, Altai, and northern Kazakhstan regions showed up at 11, 5, and 3 Ma, respectively, as a result of stress propagation into the continent, with the ensuing reactivation and mountain growth. We hypothesize that a distant effect of the Late Cenozoic India-Eurasia collision was to rejuvenate Paleozoic fault zones and to deform the Mesozoic sedimentary cover north of the collision front as far as the West Siberian Plate. The reactivation facilitated formation of tectonic oil and gas traps. The activity in northern Central Asia under the effect of the Indian indentation into Eurasia appears to continue and may evolve to include uplift of southern West Siberian plate with uplift.  相似文献   

2.
黄亮  王冬兵  王晓林  刘小春  丛峰  朱勋早  方雄 《地球科学》2021,46(11):3861-3879
滇西崇山变质杂岩带位于三江造山带"峰腰"的北段,带内构造挤压变质作用强烈,主体由一套中-深变质岩系(崇山岩群)和晚期花岗岩组成.其中崇山岩群历来被认为是元古代的结晶基底,但至今无精确的年龄依据,其形成时代和构造属性存在较大争议,严重制约了对区域构造演化的认识.对滇西漕涧地区崇山岩群中的岩石组分开展了碎屑锆石U-Pb年代学及岩石地球化学研究,结果显示副变质岩中的锆石均具明显的磨圆特征和较大的岩浆核,其中3件样品的最小一组碎屑锆石年龄分别为366~412 Ma(平均值为395 Ma)、435~508 Ma(平均值为473 Ma)和673~704 Ma(平均值为689 Ma),指示了其原始沉积时代应不早于395 Ma;岩石地球化学表明,副变质岩是一套活动大陆边缘或被动大陆边缘构造背景有关的大陆岛弧碎屑岩,变质基性岩和变质中性岩为同源异相,均具活动大陆边缘的弧火山岩特征.结合副变质岩和两类正变质岩的构造属性相同以及普遍具相互伴生关系的特点,该3类岩石应属同一套地层系统的不同物质组分,崇山岩群主体为一套成岩于晚古生代(236~395 Ma)和形成于陆缘弧环境的火山-沉积地层单元;并与南东侧澜沧增生杂岩的志留纪弧火山岩组合成原-古特提斯洋盆东侧不同时代多岛弧的构造格局.综合研究认为,崇山变质杂岩带内的中-深变质岩系(崇山岩群)不(全)是前人认为的元古代结晶基底建造,应为原-古特提斯洋盆向东俯冲在兰坪-思茅地块西缘形成的一套火山-沉积地层系统;崇山岩群主要由年轻的(晚古生代)地层岩石组成,由于后期遭受中生代和新生代变质变形作用后形成了现今所见的"古老"岩石面貌的中-深变质系.   相似文献   

3.
The depositional and metamorphic ages and provenances of the Ailaoshan(ALS) Group in the Ailaoshan-Red River(ALS-RR) shear zone, southwestern South China Block(SCB), were investigated to constrain the tectonic history of the southwestern SCB. In this study, we use petrology, geochemical analysis, zircon cathodoluminescence imaging and UPb geochronology to analyse samples of quartzite, garnet-bearing two-mica schist and metapelite. The age spectra of detrital zircon grains from these metasediments show two dominant age peaks at 550–424 Ma and 876–730 Ma and two subordinate peaks at 970–955 Ma and ~2450 Ma. The youngest peak, corresponding to the early Palaeozoic, accounts for more than 20% of the total dates and constrains the deposition of the ALS Group to the Palaeozoic rather than the Palaeoproterozoic as traditionally thought. Moreover, two peaks of metamorphic ages corresponding to the Permo-Triassic and Cenozoic were also identified, and these ages document the tectonothermal events associated with the Indosinian collision between the Indochina Block and the SCB and the Himalayan collision between the Indian and Asian plates. Geochemical data suggest that the provenances of the ALS Group were dominated by continental arc and recycled metasedimentary rocks. The comparison of probability density distribution plots of the detrital zircon U-Pb age data indicates that the Neoproterozoic detritus in the ALS Group was probably derived from the arc-related Neoproterozoic intrusive bodies in the northwestern and southwestern SCB. Furthermore, the early Palaeozoic detritus might have been sourced from eroded early Palaeozoic strata and magmatic plutons in Cathaysia and volcanic rocks in the western Indochina Block.  相似文献   

4.
柴北缘的大地构造演化及其地质事件群   总被引:10,自引:0,他引:10  
柴达木盆地北缘及邻区包括六个二级构造单元:中南祁连地块(宗务隆天山期裂陷槽)、欧龙布鲁克微陆块、柴北缘祁连期结合带、柴达木地块、东昆仑晚天山-印支期结合带(东昆北岩浆弧)和西秦岭结合带。其中柴北缘及邻区的大地构造演化,经历了前寒武纪基底成生与演化、祁连期洋-陆转化、天山-印支期板内变形和中新生代陆相盆地演化-高原隆升等四个阶段。本文在论述各个演化阶段的沉积事件、岩浆活动、变质作用、构造形迹和成矿作用等地质事件群的基础上,对柴北缘的变质基底、全球大地构造对比和显生宙花岗岩等重大基础地质问题进行了讨论。  相似文献   

5.
多旋回的板块构造运动与南海新生代构造   总被引:1,自引:0,他引:1  
何廉声 《地球学报》1984,6(2):65-74
<正> 黄汲清教授(1979)在研究板块构造演化模式时曾经强调指出:板块构造是长期的、多阶段发展的,也就是说是多旋回发展的。它包括多旋回构造运动(板块俯冲、褶皱造山),多旋回沉积建造,多旋回岩浆活动(花岗岩、火山岩等)以及多旋回找矿作用。南海及其周缘的地质构造就是板块构造多旋回发展的一个实例。本文试图根据南海及周缘地区的地质地球物理调查成果,对其新生代(包括晚白垩世)的多旋回构造作一简要概述。  相似文献   

6.
新生代以来中国大陆岩石圈尺度的大地构造分区   总被引:6,自引:0,他引:6       下载免费PDF全文
邓晋福  莫宣学 《地球科学》1997,22(3):227-232
基于大陆根柱构造概念,讨论了新生代以来大陆岩石圈尺度的大地构造分枢,地壳浅部主要表现为3种形态,即西部挤压造山带、东部大陆裂谷带和中部克拉通块体群,它们分别对应山根与造山岩石圈根、地幔热柱和大陆(岩石圈)根,认为浅部构造开矿对对壳幔深部构造的一种响应,简述了地于岩石圈度的3个大地构造单元的软流圈  相似文献   

7.
Precambrian metalliferous conglomerates are the most important source of gold, uranium, and other metals. They concentrate no less than 30% of world gold reserves and provide 30–50% of world gold production. The metalliferous conglomerates are known at various chronological levels of the Early Precambrian: the Neoarchean (Witwatersrand Supergroup, South Africa), the Neoarchean-Paleoproterozoic (Huronian Supergroup, Canada), and the Paleoproterozoic (Tarkwaian Group, West Africa; Roraima Group, the Guiana Shield; Jacobina and Sierra de Carrego groups, the Brazil Shield; Mount Bruce Group, West Australian Shield). They are related to different stages of the tectonic evolution: preorogenic stage (Huronian Supergroup), orogenic stage (Tarkwaian Group), and postorogenic or protoplatformal stage (Witwatersrand). Long-term stabilization of the Earth’s crust and deposition of thick sedimentary sequences were the most favorable conditions for the formation of metalliferous conglomerates.  相似文献   

8.
东海陆架盆地类型及其形成的动力学环境   总被引:1,自引:0,他引:1  
张建培  张田  唐贤君 《地质学报》2014,88(11):2033-2043
东海陆架盆地位于欧亚板块东南缘,处于华南陆块(包括西部的扬子地块和东部的华夏地块)之上.其基底是华夏地块在东海陆架的延伸,也是西太平洋大陆边缘构造域的重要组成部分.从全球板块构造格局分析,东海陆架盆地处于西太平洋三角带区域,是印度-澳大利亚板块和太平洋板块与欧亚板块巨型汇聚的地带,也是全球汇聚中心,其东西两侧分别与特提斯和西太平洋构造域演化息息相关.总体来说,东海陆架盆地是“欧亚板块与太平洋板块之间的碰撞、俯冲、弧后扩张,印度-澳大利亚板块与欧亚板块之间的汇聚、碰撞、楔入的远程效应,以及地球深部动力学作用”共同叠加、复合作用形成的弧后盆地.其形成机制符合被动扩张模式,向东的地幔流和软流圈下降流是导致弧后扩张的主要地球深部动力来源.  相似文献   

9.
塔里木盆地东南缘新生代构造变形特征研究   总被引:5,自引:1,他引:4  
塔里木盆地东南缘新生代变形特征研究对探讨阿尔金构造带新生代的活动特征及阿尔金构造带与西昆仑构造带的相互作用具有重要意义。本文在野外地质调查的基础上,结合地球物理和沉积学资料,探讨了塔里木盆地东南缘的新生代变形及演化特征。塔里木盆地东南缘新生代构造变形受西昆仑构造带、阿尔金构造带和车尔臣断裂带的控制,且变形由西向东减弱。西南部的构造样式主要表现为受西昆仑向北冲断作用控制的冲断构造;东南部为受阿尔金断层走滑作用控制的走滑-冲断构造;而北部则为受车尔臣断层走滑作用控制的基底卷入走滑-冲断构造。中新世,盆地东南缘受西昆仑构造带大规模的冲断活动影响,导致民丰山前盆地挠曲沉降和冲断层发育,而车尔臣断裂仅有微弱活动;上新世开始,构造变形扩展到整个研究区,不仅西昆仑构造带和车尔臣断裂带表现出强烈变形,而且阿尔金断层走滑作用强烈,导致北侧次级断层的强烈走滑冲断作用和若羌山前挤压挠曲盆地的形成。新生代时期,西昆仑构造带北向冲断作用要早于阿尔金构造带的走滑变形,阿尔金构造带的走滑作用对西昆仑构造带北向冲断构造有强烈的改造。  相似文献   

10.
碎屑组分变化是反映盆地物源演化历程的重要物质表现。路乐河地区作为柴达木盆地的重要组成部分,沉积地层记载着印度-欧亚板块碰撞以来青藏高原北缘造山带的构造隆升过程。高长石组分含量、物源方向及毗邻山脉岩性对比揭示,路乐河物源主要受南祁连和赛什腾山控制,其碎屑组分变化对毗邻造山带构造活动具有很好的耦合性。新生代53.5~2.9Ma期间,路乐河地区存在3次物源转换事件,发生时间依次同印度-欧亚板块碰撞及高原内部构造隆升事件相吻合。其中早期50.1~46.6Ma,南祁连山的快速抬升是对大陆初始碰撞的远程响应;44.5Ma,高原以垂向增生和推覆构造发育为特点,赛北断裂高速剥露,致使路乐河地区物源发生转变;渐新世末期(22.6Ma),青藏高原准同时整体隆升,赛什腾山和南祁连山协同为路乐河地区供给沉积物。所获认识为深入了解高原隆升演化和板块碰撞远程效应提供新的沉积依据。  相似文献   

11.
赖绍聪  刘池阳 《岩石学报》2001,17(3):459-468
利用岩石地球化学的方法,研究了北羌塘新生代火山岩,结果表明,北羌塘第三纪火山岩可区分为碱性(钾玄岩质)和高钾钙碱两套不同的火山岩组合,它们分别起源于一个特殊的,不均一的富集型上地幔和一个加厚陆壳的榴辉岩质下地壳,由于青藏陆块之下软流层物质的上涌而形成幔源碱性岩浆活动,而幔源岩浆在Mobo面的底侵作用又为下地壳中酸性高钾钙碱系列火山岩的起源提供了热动力条件,该区两套不同系列和源区类型的火山岩正是在这种特殊的构造环境中形成。  相似文献   

12.
A.B. Roy   《Gondwana Research》2004,7(2):387-406
The Indian crust, generally regarded as a stable continental lithosphere, experienced significant tectono-thermal reconstitution during the Phanerozoic. The earliest Phanerozoic tectonic process, which grossly changed the geological and geophysical character of the Precambrian crust, was during the Jurassic when this crustal block broke up from the Gondwana Supercontinent. There were two earlier abortive attempts to fragment the supercontinent in the Palaeozoic. Different types of geological processes were associated with these aborted events. The first was the intrusion of anorogenic alkali granites during the Early Palaeozoic (at 500±50 Ma), while the second was linked with formation of the Gondwana rift basins during Late Palaeozoic. The tectonic history of the Indian Shield subsequent to its separation from the Gondwanaland at around 165 Ma is a complex account of its northward journey, which was culminated with its collision with the northern continental blocks producing the mighty Himalayas in the process. Considerable reconstitution of the Indian Shield took place due to magma underplating when this lithospheric block passed over the four mantle plumes. While the underplating events grossly changed the geophysical character of the Indian Shield in isolated patches, the propagation of the underplated materials was assisted by the deep crustal fractures (geomorphologically expressed as lineaments), which formed during the break-up of the Gondwanaland. Several of these deep fractures evolved through the reactivation of the pre-existing (Precambrian) tectonic grains, while some others developed as new fractures in response to either the extensional stresses generated during the supercontinental break-up or the plume-lithosphere reactions. Significant geomorphological changes occurred in peninsular India subsequent to the continental collision. Most of these changes were brought about by the movements along the lineaments, which fragmented the Indian Shield into a number of rigid crustal blocks. The present day seismic behaviour of the Indian Shield is a reflection of movements of the rigid crustal blocks relative to each other. An interesting feature of the Phanerozoic geological history of the Indian Shield is the evolution of a number of sedimentary basins under different tectono-thermal regimes.  相似文献   

13.
喀什凹陷西部位于塔里木盆地、帕米尔构造带和南西天山构造带的交接处,在新生代以来接受了大量来自于南天山和帕米尔的沉积物,并记录了新生代以来南西天山构造抬升的信息。本文选择了位于南西天山山前的铁热克萨孜晚新生代剖面开展磁组构研究。铁热克萨孜剖面晚新生代沉积序列自下而上为一套整体上粒度逐渐变粗的陆相沉积,由河流湖泊相逐渐变为扇三角洲相,并最终变为冲积扇相和洪积扇相。岩石磁学结果的分析表明剖面晚新生代沉积序列中的主要磁性矿物为赤铁矿,仅在帕卡布拉克组下部为以磁铁矿为主。磁组构结果表明该剖面的磁组构为早期的同沉积弱变形磁组构,指示了当时构造应力的方向和变化。在22.1Ma以来南西天山山前晚新生代磁组构所反映的构造应力整体上为N-S向挤压,这与帕米尔和南天山的南北向持续汇聚作用相一致。在安居安组和西域组时期,应力方向由N-S向挤压变为NNE-SSW向挤压,这一变化可能是由塔拉斯-费尔干纳断裂的活动所导致的。塔拉斯-费尔干纳断裂(Talas-Fergana Fault, TFF)的右行走滑活动可能吸收了南西天山晚新生代的部分应变量,使得南西天山山前的构造应变量相对TFF以东的南天山山前地区要更小,使得TFF以东的晚新生代山前冲断带活动相对TFF以西地区更为发育和活跃。  相似文献   

14.
Siliciclastic metasediments of the Ladoga Group that is the Kalevian stratotype in Karelia correlative with the Kalevian siliciclastic succession in Finland are studied in terms of geochemistry and Sm-Nd isotopic systematics. The results obtained show that rocks in the Ladoga Group lower part are enriched, as compared to rocks of the upper part, in TiO2, Fe2O3, MgO, Cr, Co, Ni, and Sc, being comparatively depleted in Al2O3 and Th that is a result of compositional changes in provenances. The Sm-Nd isotopic data evidence that siliciclastic sediments of the Ladoga Group have accumulated during the erosion of rocks, which originated at the time of the Archean and Early Proterozoic crust-forming processes. Siliciclastic material with the Archean and Early Proterozoic TNd(DM) values, which are characteristic of metasediments in the group lower part, was derived respectively from granite gneisses of the Archean basement in the Karelian megablock of the Baltic Shield and from volcanic rocks of the Sortavala Group. Volcanic rocks of island-arc terranes of the Svecofennian foldbelt represented main source of siliciclastic material that accumulated in upper part of the succession.  相似文献   

15.
The geology of Cretaceous accretionary–collision complexes in central Indonesia is reviewed in this paper. The author and his colleagues have investigated the Cretaceous accretionary–collision complexes by means of radiolarian biostratigraphy and metamorphic petrology, as well as by geological mapping. The results of their work has revealed aspects of the tectonic development of the Sundaland margin in Cretaceous time. The Cretaceous accretionary–collision complexes are composed of various tectonic units formed by accretionary or collision processes, forearc sedimentation, arc volcanism and back arc spreading. The tectonic units consist of chert, limestone, basalt, siliceous shale, sandstone, shale, volcanic breccia, conglomerate, high P/T and ultra high P metamorphic rocks and ultramafic rocks (dismembered ophiolite). All these components were accreted along the Cretaceous convergent margin of the Sundaland Craton. In the Cretaceous, the southeastern margin of Sundaland was surrounded by a marginal sea. An immature volcanic arc was developed peripherally to this marginal sea. An oceanic plate was being subducted beneath the volcanic arc from the south. The oceanic plate carried microcontinents which were detached fragments of Gondwanaland. Oceanic plate subduction caused arc volcanism and formed an accretionary wedge. The accretionary wedge included fragments of oceanic crust such as chert, siliceous shale, limestone and pillow basalt. A Jurassic shallow marine allochthonous formation was emplaced by the collision of continental blocks. This collision also exhumed very high and ultra-high pressure metamorphic rocks from the deeper part of the pre-existing accretionary wedge. Cretaceous tectonic units were rearranged by thrusting and lateral faulting in the Cenozoic era when successive collision of continental blocks and rotation of continental blocks occurred in the Indonesian region.  相似文献   

16.
The whole-rock geochemistry of metamorphosed greywackes, arenites and arkoses within the Mesoproterozoic Namaqua-Natal-Maudheim Province is interpreted with the aim of establishing geochemical correlations and defining common sediment source terrains. Metasediments of the Mfongosi Group of the Natal Sector of the Namaqua-Natal Metamorphic Province were sampled from their type area in the Mfongosi Valley. Metagreywackes from the northern limits of the Mfongosi Valley, directly adjacent to the Kaapvaal Craton, show ocean island arc signatures while metagreywackes from the southern limits of the Mfongosi Valley, near the contact with the Madidima Thrust of the Natal nappe zone, show mainly active continental margin signatures. Interleaved, geochemically distinct low-Ca+Na, high-K metamorphosed arkoses to lithic arkoses indicate a minor passive margin sediment component. Geochemical classification of low-grade Ahlmannryggen Group greywackes, arenites and arkoses of the Grunehogna Province, Antarctica, indicates both active and passive continental margin sediment sources. An oceanic island arc signature is not evident in Ahlmannryggen Group data. The active continental margin signature in both Natal Sector and Grunehogna Province metasediments potentially provides for a common link between these terranes. Discriminant Function Analysis, using three pre-defined provenance sub-sets within the Mfongosi Group and two pre-defined provenance sub-sets within the Ahlmannryggen Group, indicate that metasediments with active continental margin signatures from both groups are geochemically identical, implying that the active continental margin of the Grunehogna Province shed immature sediments westwards (African azimuths) into the developing, narrow or restricted Mesoproterozoic ‘Mfongosi Basin.’ This was accompanied by minor sediment influx from a stable continental platform, potentially the Kaapvaal Craton. Oblique and diachronous collision, initiated in the southwestern portions of the combined Natal Sector/Grunehogna Province system produced a laterally variable Mfongosi Group, which formed in the ‘Mfongosi Basin’. Coarse-grained sediments dominated in its eastern portions while basalts with thin sapropelite units dominated in its western portions.  相似文献   

17.
理论预测与科学找矿--以西藏冈底斯斑岩铜矿为例   总被引:10,自引:0,他引:10  
近年来在西藏冈底斯构造成矿带发现了多个以斑岩铜矿为主的大型和超大型矿床,这些矿床均形成于青藏高原板内隆升过程,主要成矿年龄为17~15 Ma,其矿床类型、矿床规模、成矿部位和成矿时代与作者10 a前的理论预测结果基本吻合.突破板块碰撞造山和板块碰撞成矿模式,按大陆动力学和成矿动力学的新思路,认为冈底斯斑岩铜矿形成于特提斯开合转换、板块碰撞造陆之后的晚新生代构造隆升、下地壳层流、板内造山、地壳增厚、热隆伸展的动力改造成矿过程.加强基础地质研究、倡导创新科学思维、发展地质与成矿理论对于中国西部的找矿勘探具有十分重要的作用.  相似文献   

18.
新生代西秦岭—松甘块体向东挤出是印度—欧亚大陆碰撞后青藏东北部一种主要应变响应形式 ,它构成青藏高原东部走滑调节带的北支 ,并与南部印支挤出构造一起共同调节和吸收大陆碰撞后青藏东部的变形。西秦岭岷县—宕昌断裂的走滑与新生代盆地在时空上的耦合 ,明显展示出西秦岭—松甘块体向东走滑挤出历程并提供了走滑作用的定量标尺。古近纪岷县—宕昌断裂的走滑位移量为 36km ,而新近纪则为 76km ,相应的平均走滑速率分别为 0 .0 86mm/a和 0 .37mm/a ,表明新生代西秦岭—松甘块体向东挤出的幅度至少为 112km。西秦岭新生代幔源岩浆活动是在块体挤出背景下 ,块体旋转停止、断裂面弯曲和走滑加速等诸事件耦合的结果 ,同时也是断裂走滑的物质和时间记录器 ,表明岷县—宕昌断裂新生代的走滑波及到了岩石圈底部 ,记录了青藏东北部变形响应的动力学机制从以块体旋转为主向快速走滑为转变的时间 ,即西秦岭—松甘块体向东快速挤出的可能时间为 2 1.1~ 2 5 .4Ma。  相似文献   

19.
The East China Sea basins, located in the West Pacific Continental Margin (WPCM) since the late Mesozoic, mainly include the East China Sea Shelf Basin (ECSSB) and the Okinawa Trough (OT). The WPCM and its adjacent seas can be tectonically divided into five units from west to east, including the Min‐Zhe Uplift, ECSSB, the Taiwan–Sinzi Belt, OT, and the Ryukyu Island Arc, which record regional tectonic evolution and geodynamics. Among those tectonic units, the ECSSB and the OT are important composite sedimentary pull‐apart basins, which experienced two stages of strike‐slip pull‐apart processes. In seismic profiles, the ECSSB and the OT show a double‐layer architecture with an upper half‐graben overlapping on a lower graben. In planar view, the ECSSB and the OT are characterized by faulted blocks from south to north in the early Cenozoic and by a zonation from west to east in the late Cenozoic. The faulted blocks with planar zonation and two‐layer vertical architecture entirely jumped eastward from the Min‐Zhe Uplift to the OT during the late Cenozoic. In addition, the whole palaeogeomorphology of the ECSSB changed notably, from pre‐Cenozoic highland or mountain into a Late Eocene continental margin with east‐tilting topography caused by the eastward tectonic jumping. The OT opened to develop into a back‐arc basin until the Miocene. Synthetic surface geological studies in the China mainland reveal that the Mesozoic tectonic setting of the WPCM is an Andean‐type continental margin developing many sinistral strike‐slip faults and pull‐apart basins and the Cenozoic tectonic setting of the WPCM is a Japanese‐type continental margin developing dextral strike‐slip faults and pull‐apart basins. Thus, the WPCM underwent a transition from Andean‐type to Japanese‐type continental margins at about 80 Ma (Late Cretaceous) and a transition in topography from a Mesozoic highland to a Cenozoic lowland, and then to below sea‐level basins. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

20.
We present a review of major gold mineralization events in China and a summary of metallogenic provinces, deposit types, metallogenic epochs and tectonic settings. Over 200 investigated gold deposits are grouped into 16 Au-metallogenic provinces within five tectonic units such as the Central Asian orogenic belt comprising provinces of Northeast China and Tianshan-Altay; North China Craton comprising the northern margin, Jiaodong, and Xiaoqinling; the Qinling-Qilian-Kunlun orogenic belt consisting of the West Qingling, North Qilian, and East Kunlun; the Tibet and Sanjiang orogenic belts consisting of Lhasa, Garzê-Litang, Ailaoshan, and Daduhe-Jinpingshan; and the South China block comprising Youjiang basin, Jiangnan orogenic belt, Middle and Lower Yangtze River, and SE coast. The gold deposits are classified as orogenic, Jiaodong-, porphyry–skarn, Carlin-like, and epithermal-types, among which the first three types are dominant.The orogenic gold deposits formed in various tectonic settings related to oceanic subduction and subsequent crustal extension in the Qinling-Qilian-Kunlun, Tianshan-Altay, northern margin of North China Craton, and Xiaoqinling, and related to the Eocene–Miocene continental collision in the Tibet and Sanjiang orogenic belts. The tectonic periods such as from slab subduction to block amalgamation, from continental soft to hard collision, from intracontinental compression to shearing or extension, are important for the formation of the orogenic gold deposits. The orogenic gold deposits are the products of metamorphic fluids released during regional metamorphism associated with oceanic subduction or continental collision, or related to magma emplacement and associated hydrothermal activity during lithospheric extension after ocean closure. The Jiaodong-type, clustered around Jiaodong, Xiaoqinling, and the northern margin of the North China Craton, is characterized by the involvement of mantle-derived fluids and a temporal link to the remote subduction of the Pacific oceanic plate concomitant with the episodic destruction of North China Craton. The Carlin-like gold metallogenesis is related to the activity of connate fluid, metamorphic fluid, and meteoric water in different degrees in the Youjiang basin and West Qinling; the former Au province is temporally related to the remote subduction of the Tethyan oceanic plate and the later formed in a syn-collision setting. Porphyry–skarn Au deposits are distributed in the Tianshan-Altay, the Middle and Lower Yangtze River region, and Tibet and Sanjiang orogenic belts in both subduction and continental collision settings. The magma for the porphyry–skarn Au deposits commonly formed by melting of a thickened juvenile crust. The epithermal Au deposits, dominated by the low-sulfidation type, plus a few high-sulfidation ones, were produced during the Carboniferous oceaic plate subduction in Tianshan-Altay, during Early Cretaceous and Quaternary oceanic plate subduction in SEt coast of South China Block, and during the Pliocene continental collision in Tibet. The available data of different isotopic systems, especially fluid D–O isotopes and carbonate C–O systems, reveal that the isotopic compositions are largely overlapping for different genetic types and different for the same genetic type in different Au belts. The isotopic compositions are thus not good indicators of various genetic types of gold deposit, perhaps due to overprinting of post-ore alteration or the complex evolution of the fluids.Although gold metallogeny in China was initiated in Cambrian and lasted until Cenozoic, it is mainly concentrated in four main periods. The first is Carboniferous when the Central Asian orogenic belt formed by welding of micro-continental blocks and arcs in Tianshan-Altay, generating a series of porphyry–epithermal–orogenic deposits. The second period is from Triassic to Early Jurassic when the current tectonic mainframe of China started to take shape. In central and southern China, the North China Craton, South China Block and Simao block were amalgamated after the closure of Paleo-Tethys Ocean in Triassic, forming orogenic and Carlin-like gold deposits. The third period is Early Cretaceous when the subduction of the Pacific oceanic plate to the east and that of Neo-Tethyan oceanic plate to the west were taking place. The subduction in eastern China produced the Jiaodong-type deposits in the North China Craton, the skarn-type deposits in the northern margin (Middle to lower reaches of Yangtze River) and the epithermal-type deposits in the southeastern margin in the South China Block. The subduction in western China produced the Carlin-like gold deposits in the Youjiang basin and orogenic ones in the Garzê-Litang orogenic belt. The Cenozoic is the last major phase, during which southwestern China experienced continental collision, generating orogenic and porphyry–skarn gold deposits in the Tibetan and Sanjiang orogenic belts. Due to the spatial overlap of the second and third periods in a single gold province, the Xiaoqinling, West Qinling, and northern margin of the North China Craton have two or more episodes of gold metallogeny.  相似文献   

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