Early Paleozoic magmatism in northern Kontum Massif, Central Vietnam: Insights into tectonic evolution of the eastern Indochina Block
Early Paleozoic magmatism in northern Kontum Massif, Central Vietnam: Insights into tectonic evolution of the eastern Indochina Block
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越南中部昆嵩地块北部早古生代岩浆作用：洞察印度支那地块东部的构造演化
DOI：
10.1016/j.lithos.2020.105750
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发表时间：
2020-12
期刊：
影响因子：
3.5
通讯作者：
Fangqian Wang
中科院分区：
文献类型：
--
作者：
Wei Jiang;Jin-Hai Yu;Xiaolei Wang;W.L. Griffin;TrungHieu Pham;DinhLuyen Nguyen;Fangqian Wang
越南中部北方Kontum地块（KTM）早古生代谭基-Dai Loc Son缝合带（TPSZ）两侧的Chu Lai和Dai Loc花岗质杂岩体。对它们的成因和构造背景的研究，为探讨印支地块东部的构造演化及其与华南地块的亲缘关系提供了新的认识。锆石U-Pb定年结果表明，朱来花岗岩和大禄花岗岩分别形成于445-452 Ma和415-420 Ma。楚来花岗岩具有较高的ASI、K2 O/Na 2 O和Rb/Sr值，锆石εHf（t）为负（-14.6 ~-2.9），继承性锆石成分复杂，具有典型的S型花岗岩特征。根据花岗岩的地球化学特征，楚来花岗岩可分为两类。然而，这两个群体具有相似的锆石Hf同位素和继承锆石年龄谱，这表明他们可能来自不同程度的部分熔融的同一晚新元古代变质杂砂岩源在不同的地壳水平。Dai Loc花岗岩的常量和微量元素含量、ASI、K2 O/Na 2 O、Rb/Sr和锆石Hf同位素组成变化较大，表明它们大多数为S型花岗岩，部分为I型花岗岩，表明其来源不均一。岩石学，地球化学，地质年代学和形成温度表明，Chu Lai花岗岩形成于同碰撞环境之间的KTM和Truong Son带（TSB）和Dai Loc花岗岩碰撞后的伸展环境中的软流圈地幔上涌触发。楚来花岗岩继承锆石的年龄谱和Hf同位素组成与西华夏地块和特提斯喜马拉雅新元古代沉积岩碎屑锆石的相似性表明，它们在新元古代晚期是相邻的。KTM和TSB之间的早古生代花岗岩的年龄和锆石Hf同位素组成与SCB一致，但与东冈瓦纳北方边缘的许多微大陆不同，表明SCB与KTM和TSB接近，经历了类似的早古生代构造事件。可以推断，有一个隐蔽的早古生代俯冲带南部的SCB，连接在越南中部的TPSZ，和一个未知的大洋板块俯冲的远场效应触发了早古生代陆内造山带中的SCB。
The Chu Lai and Dai Loc granitic complexes are distributed on two sides of the early Paleozoic Tam Ky – Phuoc Son suture zone (TPSZ) in the northern Kontum Massif (KTM), central Vietnam. Studies of their petrogeneses and tectonic setting provide new insights into the tectonic evolution of the eastern Indochina Block and its affinity with the South China Block (SCB). Zircon U-Pb dating indicates that the Chu Lai and Dai Loc granites formed at 445–452 Ma and 415–420 Ma, respectively. The Chu Lai granites have high ASI, K2O/Na2O and Rb/Sr as well as strongly negative zircon εHf(t) (−14.6 to −2.9) and complex inherited zircon components, characteristics of typical S–type granites. The Chu Lai granites may be subdivided into two groups based on their geochemistry. However, both groups have similar zircon Hf isotopes and inherited–zircon age spectra, suggesting that they probably were derived from different degrees of partial melting of the same late Neoproterozoic meta–greywacke source at different crustal levels. The Dai Loc granites have variable major– and trace–element contents, ASI, K2O/Na2O, Rb/Sr, and zircon Hf–isotope compositions, indicating that most of them are S–type granites and some are I–type granites, suggesting derivation from heterogeneous sources. The petrology, geochemistry, geochronology and formation temperatures suggest that the Chu Lai granites formed in a syn–collisional setting between the KTM and Truong Son Belt (TSB) and the Dai Loc granites in a post–collision extensional setting triggered by the upwelling asthenosphere mantle. Similarities of age spectra and Hf isotope compositions of inherited zircons from the Chu Lai granites with detrital zircons from the Neoproterozoic sedimentary rocks in Western Cathaysia Block and Tethyan Himalaya suggest they are adjacent each other during the late Neoproterozoic. The ages and zircon Hf–isotope compositions of early Paleozoic granites between the KTM and TSB are consistent with those in the SCB, but different from many other microcontinents from the northern margin of East Gondwana, suggesting that the SCB was close to the KTM and TSB and experienced similar early Paleozoic tectonothermal events. It can be inferred that there was a concealed early Paleozoic subduction zone south of the SCB, connecting with the TPSZ in central Vietnam, and that the far–field effects of the subduction of an unknown oceanic plate triggered the early Paleozoic intracontinental orogeny in the SCB.
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DOI：
--
发表时间：
2016
期刊：
--
影响因子：
--
作者：
Xu Hua;Ni Zhanxu;Huang Bingcheng;Han Shupeng;Wang Cuiyun;Chen Yang
通讯作者：
Xu Hua;Ni Zhanxu;Huang Bingcheng;Han Shupeng;Wang Cuiyun;Chen Yang
影响因子：
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影响因子：
2.6
作者：
Yiming Liu;Cai Li;Chao-Ming Xie;Jian‐Jun Fan;Hao Wu;Qingyuan Jiang;Xin Li
通讯作者：
Yiming Liu;Cai Li;Chao-Ming Xie;Jian‐Jun Fan;Hao Wu;Qingyuan Jiang;Xin Li
影响因子：
3.5
作者：
Feifei Zhang;Yuejun Wang;Aimei Zhang;W. Fan;Yuzhi Zhang;Jian-Wei Zi
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Feifei Zhang;Yuejun Wang;Aimei Zhang;W. Fan;Yuzhi Zhang;Jian-Wei Zi
影响因子：
5.8
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通讯作者：
A. Draut;P. Clift