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Yang Fengqing Yin Hongfu China U niversity of Geosciences. W uhan HubeiYang HengshuNorthwestern Sichuan Geological Party Mianyang Sichuan Lai XulongChina U niversity of Geosciences. W uhan Hubei Fei Zhenbi 《《地质学报》英文版》1995,69(1)
Whether there existed the Songpan-Garze massif is a controversial problem. This paper expounds and proves that the old basement of the massif is represented by the pre-Sinian granitic rock series. This massif and the South Qinling fold belt might both be a part of the old Yangtze platform. Rifting generated by the Caledonian orogeny in the terminal Early Palaeozoic caused the massif to be disintegrated from the northwestern part of the Yangtze platform. This disintegration, however, was not thorough, and the rift troughs were later gradually closed and filled up. The Emei taphrogeny that was initiated in the Early Permian Maokou' an Stage involved a second disintegration of this massif from the Yangtze platform. The rift line largely goes along the Muli-Pingwu line. This rifting belongs to synchronous extensional rifting at peripheries of the Yangtze platform and in its interior, showing that the posterior, lateral and interior extension resulting from rapid northward shift of the Yangtze platform led t 相似文献
2.
Tectonic Development of the Proterozoic Continental Margins in East Qinling and Adjacent Regions 总被引：2，自引：0，他引：2
Wang Hongzhen 《中国地质大学学报(英文版)》1990,(1)
The East Qinling and adjacent cratonic regions belong to two geotectonicunits,the Sinokorean Subdomain including the Sinokorean Platform and itssouthern continental margin the North Qinling Belt,and the YangtzeanSubdomain comprising the Yangtze Platform and its northern continental mar-gin the South Qinling Belt.The Qinling region may thus be subdivided into twocontinental margin belts separated from each other by the Proterozoic Qinlingmarine realm,which did not disappear until Late Triassic.The convergentcrustal consumption zone,the megasuture between the two belts,lies betweenthe Fengxian-Shangnan line in the north and the Shanyang-Xijia line in thesouth and was much deformed and displaced through Mesozoic intracratoniccollision and compression.In the northern subdomain the Lower Proterozoic is representedby protoaulacogen volcano-sediments,the inner Tiedonggou Group and theouter marginal Qinling Group,which were folded and metamorphosed in theLuliangian orogeny,a general process of aggregation and s 相似文献
3.
Geochemical characteristics of the Neoproterozoic basic dykes widely exposed in the Wudang block of South Qinling show that the dykes possess the characteristics of continental tholeiitic basalts and were formed in a setting of continental rifting.Therefore,there was an ancient continental block in the areas of southern Qinling and Yangtze block during the Jinning period,and an important firting event of this ancient block occurred in the Early Neoproterozoic. 相似文献
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中-晚二叠世,上扬子(四川盆地区)碳酸盐岩台地内发育三条北西-南东走向的裂谷,它们是重要的油气储集区带,如普光和元坝气田就产于开江-梁平裂谷两侧。但是对这些裂谷的开始时代和构造成因等关键地质问题,还缺乏详细的沉积学研究,且存在较大争议。本文通过大比例露头剖面和钻井岩芯测量以及详细的沉积相分析对比,对开江-梁平裂谷的构造沉积过程进行了深入细致的研究。调查发现,在开江-梁平裂谷北缘,中二叠统栖霞组上段至茅口组2段发育大规模斜坡相碳酸盐岩滑塌堆积,揭上扬子地块四川盆地区于中二叠世栖霞晚期开始发生伸展裂解。茅口组3段至上二叠统长兴组为超覆于滑塌堆积之上的硅质岩和碳-硅质泥岩等深水盆地相沉积,表明开江-梁平裂谷从中二叠世茅口晚期开始由伸展裂解转变为区域沉降,即开江-梁平裂谷经历了伸展裂解和区域沉降两个构造沉积阶段。伸展裂解阶段,开江-梁平裂谷是一个发育于碳酸盐岩台地内的不对称海相半地堑盆地,北侧为发育大规模碳酸盐岩滑塌堆积的下盘断斜坡带,南侧为发育缓斜坡生物碎屑滩和礁灰岩的上盘缓斜坡带;区域沉降阶段,开江-梁平裂谷表现为东翘西降的不均匀沉降,发育自东向西不断进积的潮坪-潟湖相和高能浅滩相沉积等。本文研究成结果对分析和圈定四川盆地区中-晚二叠世油气储集相带的时空分布具有重要科学意义,也为研究碳酸盐岩滑塌堆积提供了一个新范例。 相似文献
5.
扬子地块北缘晚古生代-早中生代裂谷系统的分布及成因分析 总被引：5，自引：4，他引：1
晚二叠世长兴期-早三叠世印度期,在扬子地块的西北缘发育了一系列北西向展布的深水盆地区。根据成因分析证实,它们为伸展背景下形成的裂谷系统或者裂谷盆地群。平面上各裂谷盆地彼此近于平行,与北侧的南秦岭造山带在走向上呈正交和大角度斜交的排列,自西向东依次为开江-梁平裂谷、城口-鄂西裂谷和荆门-当阳裂谷。其中的开江-梁平裂谷东西两侧发现了巨大的天然气田而引起石油勘探家和地质学家的关注。本文对于这些控制油气资源储备的裂谷体系的分布和形成机制进行研究后,认为它们形成于南秦岭洋闭合时的碰撞作用,是南秦岭造山带和扬子地块拼合时同生的巨型"碰撞裂谷系统"。 相似文献
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南秦岭勉略古缝合带非史密斯地层和古海洋新知 总被引：12，自引：3，他引：9
南秦岭勉略古缝合带是一个构造混杂岩型非史密斯地层区,由不同时代的原地地层系统和异地地层系统的构造岩片构成。泥盆纪—石炭纪硅质岩的常量元素、稀土元素分析结果指示了勉略小洋盆的存在。区域背景分析表明晚震旦世到早寒武世,南秦岭为扬子板块北部边缘的一部分,中、晚寒武世以后开始分裂形成南秦岭裂陷槽。该海槽于中、晚志留世萎缩但未关闭,泥盆纪又进一步开裂逐渐形成大陆边缘裂谷盆地,晚泥盆世后期到早石炭世早期形成一开放小洋盆。早石炭世后期出现洋壳俯冲,从而转化为活动大陆边缘盆地。该洋盆可能持续到二叠纪,并于印支期最终关闭、碰撞和造山。 相似文献
8.
北秦岭元古代构造格架与演化 总被引：9，自引：1，他引：9
秦岭造山带是经历了多阶段的多陆块长期裂解、拼合的复合型造山带。最新的地质、地球化学和同位素年代学综合研究共同揭示沿商丹带分布有中新元古代蛇绿岩,并伴生有与板块俯冲碰撞作用相关的弧后盆地、岩浆弧、高压变质作用,表明北秦岭于中元古代末—新元古代初曾发展成为类似于现代板块构造体制的活动大陆边缘,出现板块向北俯冲消减、弧后盆地的生成和蛇绿岩构造侵位及其后的碰撞造山作用。 相似文献
9.
秦岭三叠系分带及印支期发展史 总被引：7，自引：0，他引：7
秦岭及共邻区的三叠系自北而南可分为四带.北秦岭三叠系具有富含植物化石的陆相上三叠统,其下的优地槽型细碧角斑岩系时代未定.中秦岭下三叠统为复理石夹多层砾状灰岩,后者系斜坡沉积,物源可能来自北方,安尼期为复理石.南秦岭北带在二叠纪晚期已裂陷接受复理石及以砾状灰岩为代表的斜坡沉积.早三叠世至安尼期为深水相黑色板岩、薄层灰岩、复理石并夹火山岩.南秦岭南带及巴顿喀喇从早三叠世至安尼期为扬子地台的一部分,岩相及化百群与之一致,具有发育良好的安尼期陆棚边缘生物滩.从拉丁期开始裂陷．出现鱼鳞蛤页岩、砾状灰岩及巨厚复理石,后者延续至晚三叠世,有放射虫为证.整个中,南秦岭呈现一个由二叠纪晚期开始,延续于印支期的裂陷槽发育史.它的北部—中秦岭和南秦岭北带于二叠纪末及三叠纪初先后裂陷,并于拉丁期褶皱回返.它的南部—南秦岭南带及巴颜喀喇于拉丁期裂陷,并于三叠纪末回返.这个裂陷槽是否构成印支期秦岭的主体,抑或它仅是“北秦岭小洋盆”在扬子大陆边缘的弧后扩张盆地,取决于北秦岭是否存在早、中三叠世优地槽沉积.后者尚未证实. 相似文献
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11.
秦岭及其邻区地处华北地台南缘、秦岭地槽、松潘 甘孜地块、扬子地台北缘 ,可划分皖鄂、鄂西、陕南、什 (邡 )绵 (竹 )等 4个磷矿密集区。成矿时代自元古宙至泥盆纪 ,以震旦纪、寒武纪为高峰期。矿床以沉积型为主 ,次为沉积变质型及岩浆型。特大型、大型矿床成矿受海盆地控制 ,中、小型矿床则受海沟、海槽或海湾制约。区内可归纳出 3级成矿远景区 ,8个成矿域 相似文献
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扬子地块与南秦岭造山带的盆山系统与构造耦合 总被引：12，自引：3，他引：9
本文重新厘定了扬子地块西北缘晚古生代至早中生代沉积盆地的原型,在综合分析南秦岭造山带和勉略缝合带形成规律的基础上,对于南秦岭造山带与扬子地块北缘的拼合演化历史以及盆山耦合关系进行了研究。指出在晚二叠世晚期(长兴组沉积上段)和早三叠世早期(飞仙关组沉积下段)发生点式碰撞,在两个不同的大地构造单元之间形成了与碰撞相关的裂谷盆地群(包括开江-梁平裂谷、城口-鄂西裂谷和东部的当阳裂谷等),碰撞裂谷群的持续演化时间为5~6Ma,这一阶段典型的沉积标志为水下早期阶段形成的海相磨拉石层序。至早三叠世的嘉陵江二段沉积时期,两个不同地块的持续拼合导致大巴山和米苍山地区与周缘前陆盆地相关的古冲断带的形成,该阶段在缝合带接触部位发育角度不整合和河流相沉积,扬子地块其余大部仍然是保持连续的海相碳酸盐岩沉积。晚三叠世南秦岭造山带与扬子北缘之间的残余大洋消失,为整体闭合的碰撞后期阶段,沉积了须家河组开始的陆相碎屑岩系,大巴山和米苍山地区进入到了以陆相磨拉石为主的前陆盆地阶段,在扬子北缘形成了神农架-黄陵隆起和米苍山隆起。晚三叠世以后大巴山和米苍山地区进入了比较复杂的后期改造阶段,产生了多期的收缩性构造活动,包括以形成区域性的假整合和小角度不整合为特征的晚侏罗世-早白垩世早期(J3-K1)的低幅度活动期;以大巴山和米苍山冲断带的强烈改造为主,形成薄皮冲断构造系统的早白垩世晚期变形和以形成大巴山弧形冲断带和米苍山基底卷入的冲断带为特征的新生代晚期变形。 相似文献
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广西钦防地区位于扬子地块和华夏地块结合带的西南段,是华南唯一的海相志留系与下泥盆统连续沉积出露区.对钦防地区志留系地层中的沉积岩展开了精细的LA-ICP-MS锆石U-Pb年代学分析和测试.分析结果表明,7个代表性沉积岩样品的年龄频谱图显示出了~2.5 Ga、~1.0 Ga、~0.47 Ga 3个明显的年龄峰值,暗示太古代全球地壳生长事件（~2.5 Ga）、格林威尔期造山运动（~1.0 Ga）以及早古生代构造事件（~0.47 Ga）在华南地区保存有记录.结合锆石的阴极发光图像特征和相关区域地质资料,推测~2.5 Ga、~1.0 Ga和~0.47 Ga碎屑锆石均主要来源于钦防地区东北侧的云开地块,钦防地区与华夏地块具有亲缘性,早古生代时期钦防地区可能为一夭折的裂谷,这一时期华夏与扬子地块西南端的分界线至少位于钦防地区的西北侧. 相似文献
14.
Geochemistry of the Caledonian basic volcanic rocks at the south margin of the Qinling orogenic belt, and its tectonic implications 总被引：1，自引：0，他引：1
The geochemistry of the basic volcanic rocks at the south margin of the Qinling orogenic belt(SMQOB) suggests that they were formed in an intraplate tectonic setting.The REE distribution patterns show these rocks are strongly enriched in LREE with high ∑REE, and their trace elements geochemistry is similar to that of contimental flood basalt.All the above evidence suggests that the Caledonian basic volcanic rocks in the SMQOB were tholeiitic basalts formed in an intraplate spreading-initial rift tectonic setting.The characteristics of regional geology and geochemistry indicate that there was an intraplate spreading-rift tectonic setting between the South Qingling block and the Yangtze block in the Caledonian epoch.The dynamic spreading in this district began in the Early Caledonian and then the intraplate spreadinginitial rifts were formed in the Late Caledonian.As a result of spreading of the Tethys and geodynamic processes in deep mantle ,the Mianlue-Huashan oceanic basin was formed between the Qinling block and the Yangtze block in Devonian,and the Qinling microplate was separated from the northern part of the Yangtze plate. 相似文献
15.
秦岭造山带以商丹断裂带为界分为南秦岭和北秦岭。南秦岭在早古生代是扬子板块的被动大陆边缘,在志留纪末曾因垂向隆升变为古陆。因其南缘长期处于地幔上涌的构造薄弱带,所以到泥盆纪首先从这里开始扩 张,并逐渐演化成有限洋盆,与扬子板块分离,成为独立的板块,内部也因拉张形成裂陷盆地与块断隆起相间的环境格局。其自南而北依次为安康古陆→旬阳-镇安盆地→小磨岭古陆→刘岭盆地。在盆地内堆积了从陆相到海相,从浅水到深水的各种沉积体系,组成向上变细和变深的充填序列。而在北侧,该板块仍在向华北板块下面俯冲。北秦岭南缘的弧前沉积体系记录了这种俯冲作用的演化。这种与早古生代十分不同的古地理格局标志秦岭造山带已进入了新的演化阶段。 相似文献
16.
安徽沿江中新生代盆地位于大别山造山带南缘，为先挤压、后伸展形成的叠合盆地，是探讨扬子板块陆内深俯冲—大别山造山带隆起与中、下扬子盆地沉降的耦合关系的理想场所。在早中生代，大别山为华南和华北大陆碰撞造山带，华南地壳向深处俯冲并承受超高压变质作用，超高压变质岩不断向上折返，沿江坳陷具有前陆盆地性质，盆地充填有晚三叠世—中侏罗世磨拉石层序；在晚中生代，在中国东部整体的拉张背景下，大别山变质带完全折返上隆，处于变质核杂岩隆升状态，而沿江坳陷具有裂陷盆地性质，充填有晚侏罗世—早白垩世、晚白垩世—古近纪两个红色碎屑构造层序，起因于地壳拆沉而产生的均衡隆升和伸展断陷的构造耦合。 相似文献
17.
秦岭早古生代沉积作用与构造演化 总被引：3，自引：0，他引：3
根据对秦岭及其两侧地台区沉积体系与旋回沉积的分析，认为该区在早古生代总体上处于板块的扩张阶段，其中巨厚的台地碳酸盐岩的广布的远洋沉积是其典型岩相。早奥陶世阿伦尼克中期华北地台南的一度隆升与剥蚀，标志着俯冲作用开始，但未发现加里东期碰撞造山作用的证据。该区晚奥陶世一志留纪大规模的海退主要是全球海平面下降的结果，与碰撞造山人关系不大。 相似文献
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南秦岭中,新元古代地层划分对比新认识 总被引：6，自引：0，他引：6
在运用板块动力学模式研究晚前寒武纪地层划分对比问题的基础上,根据南秦岭构造带区域地质的实际情况,提出在中、新元古代南秦岭曾经历了晋宁期造山作用和澄江期裂解作用两次重大构造事件,它们控制了区内不同岩石建造的形成和时,空分布,据此对区域内中,新元古代地层的划分对比提出了新的认识。 相似文献
19.
A new concept on tectonic correlation between Korea, China and Japan: Histories from the late Proterozoic to Cretaceous 总被引：11，自引：2，他引：11
Chang Whan Oh 《Gondwana Research》2006,9(1-2):47
The Dabie–Sulu collision belt in China extends to the Hongseong–Odesan belt in Korea while the Okcheon metamorphic belt in Korea is considered as an extension of the Nanhua rift within the South China block. The Hongseong–Odesan belt divides Korea's Gyeonggi massif into northern and southern portions. The southern Gyeonggi massif and the Yeongnam massif are correlated with China's Yangtze and Cathaysia blocks, respectively, while the northern Gyeonggi massif is part of the southern margin of the North China block. The southern and northern Gyeonggi massifs rifted from the Rodinia supercontinent during the Neoproterozoic, to form the borders of the South China and North China blocks, respectively. Subduction commenced along the southern and eastern borders of the North China block in the Ordovician and continued until a Triassic collision between the North China and South China blocks. While subduction was occurring on the margin of the North China block, high-P/T metamorphic belts and accretionary complexes developed along the inner zone of southwest Japan from the Ordovician to the Permian. During the subduction, the Hida belt in Japan grew as a continental margin or continental arc. Collision between the North and South China blocks began in Korea during the Permian (290–260 Ma), and propagated westwards until the Late Triassic (230–210 Ma) creating the sinistral TanLu fault in China and the dextral fault in the Hida and Hida marginal belt in Japan. Phanerozoic subduction and collision along the southern and western borders of the North China block led to formation of the Qinling–Dabie–Sulu–Hongseong–Hida–Yanji belt. 相似文献
20.
根据大地构造单元及地质背景条件与磷矿特征,秦岭地区划分４个成磷区,即华北、秦岭、扬子与摩天岭区。磷矿主要形成于晚震旦世和早寒武世。其间发育着不同岩石,构成各种类型矿石。磷矿的形成与陆源物质、有机质及铀矿关系密切。磷矿层处于“继承陆源碎屑”建造或“造海蒸发岩碳酸盐”建造中,特别是两种建造过渡带。矿床形成在地壳比较平静时期与造海运动关系密切。在扬子区北缘磷矿床通常赋存于“古地形高地”或“水下隆起”周围,常呈带状。扬子地台区北缘（摩天岭区）比华北地台南缘对子磷矿床形成更为有利。 相似文献