摘要
位于青藏高原北缘的西昆仑—喀喇昆仑造山带经历了原特提斯—中(新)特提斯阶段长期的构造演化,形成了复杂的岩石组合及结构—构造特征。在长期演化过程中,西昆仑—喀喇昆仑造山带形成了独特的成矿系列。本文对西昆仑—喀喇昆仑造山带基本结构、物质组成及构造演化进行总结,并讨论了不同构造演化阶段的成矿效应。西昆仑—喀喇昆仑主体分为四个主要构造单元,分别是北昆仑地体、南昆仑地体(包括以布伦阔勒群为主体的塔什库尔干地体)、麻扎尔—甜水海地体及喀喇昆仑地体。北昆仑地体代表了塔里木基底的一部分,记录了从古元古代早期到新元古代的构造演化及其对Columbia、Rodinia超大陆汇聚和裂解的响应。麻扎尔—甜水海地体是由塔什库尔干县南部新太古代变质火山沉积岩系(基底)及甜水海地区南华纪具有被动大陆边缘沉积特征的盖层岩系组成的一个完整的前寒武纪微陆块,这一微陆块和扬子地区的前寒武系具有显著的亲缘性,它与柴达木地块、祁连地块、北阿尔金地块等均是在Rodinia超大陆裂解过程中从扬子地块裂解出来的微地块群;南昆仑地体和塔什库尔干地体内的角闪岩相到麻粒岩相变质火山—沉积岩系形成于早古生代,而不是前寒武纪基底建造,它们共同构成了西昆仑地区早古生代巨型增生杂岩,这一增生杂岩是原特提斯洋长期向麻扎尔—甜水海地体之下俯冲的结果,包含了弧前增生杂岩、洋岛、岛弧火山—沉积岩及蛇绿混杂岩等。原特提斯洋的俯冲结束于440 Ma左右,使南昆仑地体发生角闪岩相变质。原特提斯洋的关闭事件在西昆仑、柴北缘、北祁连、北秦岭以及华夏地区都有记录,这一过程导致了塔里木、柴达木、北祁连、北秦岭、扬子及印支地块汇聚到东冈瓦那北缘。古特提斯洋大约于晚泥盆世—早石炭世打开,与弧后�
Objectives:The Western Kunlun—Karakorum Orogenic Belt(WKOB),located the most northern margin of the Qinghia—Xizang(Tibet)Plateau,underwent the time-integrated Tethys evolution process and exhibits distinct rock packages and tectonic signatures.Particularly,several key metallogenic series were formed during its long evolution history.The aims of this study include(1)having a sketch on its texture,rock packages and tectonic evolution process and(2)decoding the coupling between its tectonic evolution and domino mineralization effect.Methods:Synthesizing the recent studies on the regional geology,deposit exploration results.Results:The WKOB could be divided into four main units,i.e.,the Northern Kunlun terrane(NKT),the Southern Kunlun terrance(SKT),the Mazar—Tianshuihai terrane(MZTT)and the Karakorum terrane(KAT).The NKT,as a member of the Tarim Precambrian basement,had undergone the assemblage and breakup of the late Paleoproterozoic Columbia and the early Neoproterozoic Rodinia supercontinents.The MZTT is composed by the Neoarchean metamorphic bimodal volcanic sequences(the basement)in southern Tashikorgan and the Nanhuaian clastic sedimentary sequences(the cover sequences).It shows significant affinity with the Yangtze and,together with the Qaidam,Qilian and Northern Althyn terranes,could be continental fragments drifted from Yangtze during the breakup of the Rodinia.The amphibolite-to granulite-facies metamorphic volcanic—sedimentary sequences in SKT deposited during late Sinian to early Ordovician during the southward subdution of the Proto-Tethys Ocean under the MZTT.They exhibit features of typical accretionary complex composing of fore-arc accretion sequences,intraocean arc,arc and ophiolites.The Proto-Tethys Ocean closed at ca.440~430 Ma and this process induced the MZTT,Qaidam,Qilian and Northern Qinling terranes docking at the northern margin of the Eastern Gondwana.The opening of the Paleo-Tethys Ocean took place at early Carboniferous as demonstrated by the Carboniferous rifting volcanic rocks di
作者
张传林
马华东
朱炳玉
叶现韬
邱林
赵海香
刘晓强
丁腾
王倩
郝晓姝
ZHANG Chuanlin;MA Huadong;ZHU Bingyu;YE Xiantao;QIU Lin;ZHAO Haixiang;LIU Xiaoqiang;DING Teng;WANG Qian;HAO Xiaoshu(College of Oceanography,Hohai University,Nanjing,210098;National 305 Project Office,Urumuqi,830000)
出处
《地质论评》
CAS
CSCD
北大核心
2019年第5期1077-1102,共26页
Geological Review
基金
新疆维吾尔自治区科技重大专项项目所属课题“喀喇昆仑构造岩浆演化与稀有金属成矿地质背景研究”(编号:2018A03004-1)的成果~~
关键词
西昆仑—喀喇昆仑造山带
特提斯洋
构造演化
成矿效应
Western Kunlun—Karakorum orogenic belt
Tethys Ocean
tectonic evolution
mineralization effect
