Late Silurian to early Devonian development of the Chingiz accretion arc, West Junggar: insights into accretion arc evolution in the Central Asia Orogenic Belt
Late Silurian to early Devonian development of the Chingiz accretion arc, West Junggar: insights into accretion arc evolution in the Central Asia Orogenic Belt
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西准噶尔成吉思特增生弧晚志留世至早泥盆世的发育：中亚造山带增生弧演化的见解
DOI：
10.1080/00206814.2020.1824128
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发表时间：
2020-09
影响因子：
2.6
通讯作者：
Wu Chunming
中科院分区：
文献类型：
--
作者：
Chen Yichao;Zhang Ji'En;Xiao Wenjiao;Zhou Renjie;Song Shuaihua;Zhang Zhiyong;Ao Songjian;Sang Miao;Zhang Qian W. L.;Li Rui;Li Zhen M. G.;Liu Yin;Zhang Hui C. G.;Liu Jiahui;Wu Chunming
中亚造山带哈萨克斯坦造山带早古生代的演化是重建中亚古生代构造格局的关键。本文通过对西准噶尔北方乌拉斯台地区的野外地质填图、地球化学和年代学资料的分析，探讨了哈萨克斯坦造山带成吉兹弧早古生代的俯冲极性和主要构造事件。填图区域出露叠瓦状相干浊积岩片和混杂岩，由泥岩基质中的燧石、石灰岩、粉砂、砂岩和砾岩块组成，代表增生杂岩中的OPS（海洋板块地层学）混杂岩。这些地块的现有化石年龄范围从奥陶纪到志留纪，而我们新的碎屑锆石U-Pb样品从浊积岩基质产生的最大沉积年龄（MDT）为428 ± 2 Ma至450 ± 1 Ma。碎屑锆石年龄~510至430 Ma的混杂岩建议Chingiz弧南部的研究领域作为一个主要的沉积物源，提供了一个间接的约束俯冲的极性。我们认为，成吉兹弧北方部分可能受到向南俯冲的影响，增生杂岩位于西准噶尔北方乌拉斯台地区。乌拉斯台混杂岩被亏损HFSE、富集LILE、LREE的火山岩沉积覆盖。安山岩和凝灰岩的年龄分别为415 ± 5 Ma、414 ± 3 Ma和402 ± 6 Ma，反映了火山弧在俯冲杂岩上的发展。这一模型暗示了板块回滚和海沟后退过程中弧（增生弧）的产生，这可能在CAOB的演化历史中起着重要作用。
ABSTRACT Early Palaeozoic evolution of the Kazakhstan orocline in the Central Asian Orogenic Belt (CAOB) is key to reconstructing the Palaeozoic tectonic framework in Central Asia. This study presents field mapping, geochemistry, and geochronological data from the Wulasitai area of northern West Junggar to constrain the subduction polarity and major tectonic events in the Chingiz arc of the Kazakhstan orocline during the Early Palaeozoic. The mapping area outcrops imbricated coherent turbidite slices and mélanges that consist of chert, limestone, silt, sandstone, and conglomerate blocks in mudstone matrix, representing an OPS (Ocean Plate Stratigraphy) mélange in an accretionary complex. Existing fossil ages from these blocks range from the Ordovician to Silurian, while our new detrital zircon U-Pb samples from the turbiditic matrix yield maximum depositional ages (MDTs) from 428 ± 2 Ma to 450 ± 1 Ma. Detrital zircon ages of ~510 to 430 Ma in the mélange suggest the Chingiz arc to the south of the study area as a major sediment source, providing an indirect constraint on the polarity of subduction. We suggest that the northern part of the Chingiz arc may be underlain by southward subduction, with the accretionary complex located on the Wulasitai area of the northern West Junggar. The Wulasitai mélange is overlain depostionally by volcanic rocks carrying depleted HFSE and enriched LILE, LREE. The andesite and tuff are dated to 415 ± 5 Ma, 414 ± 3 Ma, and 402 ± 6 Ma, which we interpret as reflecting the development of the volcanic arc onto the previous subduction complex. This model implies the generation of the arc (accretion arc) as the slab rolling back and trench retreating, which may play an important role in the evolutionary history of CAOB.
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影响因子：
6.1
作者：
S. Buckman;A. Nutman;J. Aitchison;J. Parker;Sarah Bembrick;Tom Line;H. Hidaka;Tomoyuki Kamiichi-Tomoyuki-Kamii
通讯作者：
S. Buckman;A. Nutman;J. Aitchison;J. Parker;Sarah Bembrick;Tom Line;H. Hidaka;Tomoyuki Kamiichi-Tomoyuki-Kamii
影响因子：
2.6
作者：
J. Wakabayashi
通讯作者：
J. Wakabayashi
DOI：
10.1146/annurev-earth-060614-105254
发表时间：
2015-06
影响因子：
14.9
作者：
W. Xiao;B. Windley;S. Sun;Jiliang Li;Baochun Huang;Chunming Han;C. Yuan;Minjia Sun;Hanlin Chen-Hanli
通讯作者：
W. Xiao;B. Windley;S. Sun;Jiliang Li;Baochun Huang;Chunming Han;C. Yuan;Minjia Sun;Hanlin Chen-Hanli
影响因子：
1.8
作者：
Zhu Yong
通讯作者：
Zhu Yong
中亚造山带西部：增生造山作用和大陆生长的窗口
影响因子：
6.1
作者：
Wenjiao Xiao;M. Santosh
通讯作者：
M. Santosh