东亚原特提斯洋(Ⅱ):早古生代微陆块亲缘性与聚合  

Proto-Tehtys Ocean in East Asia(Ⅱ) : Affinity and assmbly of Early Paleozoic micro-continental blocks

作　　者：李三忠[1,2] 赵淑娟[1,2] 余珊[1,2] 曹花花[1,2] 李玺瑶 刘鑫[1,2] 郭晓玉[3] 肖文交[4] 赖绍聪[5] 闫臻[3] 李宗会[6] 于胜尧[1,2] 张剑[1,2] 兰浩圆 

机构地区：[1]中国海洋大学海洋地球科学学院海底科学与探测技术教育部重点实验室,青岛266100 [2]青岛海洋科学与技术国家实验室海洋地质功能实验室,青岛266061 [3]中国地质科学院地质研究所,北京100037 [4]中国科学院地质与地球物理研究所,北京100029 [5]西北大学地质学系,西安710069 [6]中国地质调查局西安地质调查中心,西安710054

出　　处：《岩石学报》2016年第9期2628-2644,共17页Acta Petrologica Sinica

基　　金：国家自然科学基金重大项目(41190072;41190070);国家杰出青年基金项目(41325009);泰山学者特聘教授项目;鳌山卓越科学家计划联合资助

摘　　要：原特提斯洋内存在塔里木、中祁连、柴达木、扬子、华夏、印支、兰坪-思茅等诸多陆块/微陆块,多数陆块之间在早古生代晚期发育有蛇绿岩带或高压-超高压带。原特提斯域形成于从Rodinia裂解到Pangea超大陆集结期间,存在复杂的洋-陆格局和聚散过程。原特提斯洋不同陆块/微陆块属性和关系及其拼合过程是恢复重建Pangea超大陆聚合前构造背景的关键,但对其认识迄今还存在争论。因此,本文采用综合对比方法,以期建立原特提斯洋陆块/微陆块的亲缘性和海-陆格局,厘定原特提斯微陆块拼合时序与方式。结果表明,早古生代早期除华北陆块不具有亲冈瓦纳大陆的特征外,扬子、华夏、塔里木、柴达木、阿拉善、北秦岭-中祁连-中阿尔金、欧龙布鲁克、北羌塘、南羌塘、拉萨、兰坪-思茅、印支等陆块/微陆块都具有亲冈瓦纳的特征。在450-400Ma左右这一系列陆块/微陆块都向南俯冲-增生,并逐步拼合于冈瓦纳大陆北缘东段,原特提斯洋关闭,并形成了原潘吉亚（Proto-Pangea）超大陆;原潘吉亚于380Ma以后裂离出塔里木-华北陆块和大华南陆块,分别出现勉略洋和古特提斯洋,直到240~220Ma逐步向北聚合,形成最终的劳亚古陆,此时才形成潘吉亚超大陆。In the Proto-Tethys Ocean there are many microcontinents/continents such as the Tarim, Qilian, Qaidam, Yangtze and Cathaysia, Indochina, Lanping-Simao （Sibumasu） blocks/micro-continental blocks, between most of these blocks developed a series of ophiolite belts or high-pressure and ultrahigh-pressure metamorphic belts at the end of the Early Paleozoic. Obviously, the Proto- Tethyan tectonic domain underwent the complex ocean-continent configuration, break-up and assembly processes from Supercontinent Rodinia＇ s breakup to Supercontinent Pangea＇ s assembly. However, so far their attribute, affinity and collision process among different continents/microcontinents in the Proto-Tethys Ocean remain much controversy. This is critical for restoration and reconstruction of tectonic background of Supercontinent Pangea assembly. Therefore, this paper adopts the comprehensive tectonic comparison method in order to establish affinities and ocean-continent configuration of the Proto-Tethys Ocean and the related continental block/microcontinental blocks, and determine the timing and sequences of assembly among these Proto-Tethyan micro-continental blocks. The results show that, the North China Block had not affinitive relation to the Gondwana, the other continents/micro-continental blocks such as the Yangtze, Cathaysia, Tarim, Qaidam, Alax, North Qinling-Central Qilian-Central Ahyn, Oulongbuluke, North Qiangtang, South Qiangtang, Lhasa, Lanping-Simao and Indochina have an affinity to Gondwana in the earlier of Early Paleozoic. During about 450 - 400Ma these series of continental blocks/micro-continental blocks experienced gradually southward subduction and accretion to the eastern segment of the northern margin of the Gondwana, resulting in the Proto-Tethys Ocean closure and one supercontinent called Proto-Pangea. The Tarim-North China Block and the Greater-South China Block separated from the Proto-Pangea since 380Ma to result in formation of the Mianlue and the Paleo-Tethys oceanic crusts. Until 240 ~ 220Ma they asse

关 键 词：原特提斯 微陆块 早古生代 东亚 亲缘性 

分 类 号：P542[天文地球—构造地质学]