Late Palaeozoic tectonic evolution of the eastern Palaeo-Asian Ocean: new evidence from the early Permian arc magmatic suites in the Kulun region
Late Palaeozoic tectonic evolution of the eastern Palaeo-Asian Ocean: new evidence from the early Permian arc magmatic suites in the Kulun region
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古亚洲洋东部晚古生代构造演化：来自库伦地区早二叠世弧岩浆套的新证据
DOI：
10.1017/s0016756822000358
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发表时间：
2022-07
影响因子：
2.3
通讯作者：
Dehe Xing
中科院分区：
文献类型：
--
作者：
Yan Jing;Wen-chun Ge;Hao Yang;Yu Dong;Zheng Ji;Jun-hui Bi;Hong-ying Zhou;Dehe Xing
摘要 晚古生代火成岩组合对古亚洲洋东部俯冲、增生和最终闭合的响应对于理解中亚造山带东南部的地球动力学演化具有重要作用。先前的研究已经确定了一条二叠纪弧岩浆带，该岩浆带与古亚洲洋东部沿索伦克-长春缝合带向南倾斜的俯冲有关。成因机制和相关的地球动力学背景对于破译古亚洲洋东部的演化具有重要意义。本文介绍了库伦地区早二叠世闪长玢岩（约 281.0 Ma）、安山岩（约 276 Ma）和流纹岩（约 275 Ma）等岩浆岩的锆石 U-Pb-Hf 同位素和全岩地球化学分析。闪长玢岩和安山岩的SiO 2 和总碱含量较高，而MgO 含量和Mg 含量较低。值，大离子亲石元素富集，高场强元素耗尽。这些地球化学特征，加上低Sr和高Yb含量、中稀土元素呈弱凹向上形状以及Eu负异常，表明这些中间火成岩是由地壳深度30-40 km的角闪岩下地壳部分熔融生成的。流纹岩具有异质同位素组成，ε Hf ( t ) 值和 T DM2 年龄为 –20.8 至 +0.5 和 3578∼1494 Ma，这意味着它们可能源自以回收的古代地壳和少量新生地壳物质为主的混合来源的部分熔融。流纹岩与相对较高的K 2 O和非常低的Na 2 O表现出钾亲和力，这归因于长英质岩浆的液体不混溶性和随后的斜长石的有限分级结晶。索伦克-长春缝合带沿线的区域火成岩组合、变质事件和同时代沉积岩表明，早二叠世火成岩是在活跃的大陆弧环境中形成的，响应于东部古亚洲洋的南向俯冲。
Abstract Late Palaeozoic igneous rock associations in response to subduction, accretion, and final closure of the eastern Palaeo-Asian Ocean play a significant role in understanding the geodynamic evolution of the southeastern Central Asian Orogenic Belt. Previous studies have identified a Permian arc magmatic belt associated with the southward-dipping subduction of the eastern Palaeo-Asian Ocean along the Solonker–Changchun suture zone. The genetic mechanism and associated geodynamic settings are of great importance in deciphering the evolution of the eastern Palaeo-Asian Ocean. This paper presents zircon U–Pb–Hf isotope and whole-rock geochemical analyses for a suite of magmatic rocks including the early Permian diorite porphyrites ( ca . 281.0 Ma), andesites ( ca . 276 Ma) and rhyolites ( ca . 275 Ma) in the Kulun region. The diorite porphyrites and andesites have high SiO 2 and total alkali contents, and low MgO contents and Mg no. values, with enrichments in large ion lithophile elements and depletions in high-field-strength elements. These geochemical characteristics, together with low-Sr and high-Yb contents, a weak concave-upward shape of middle rare earth elements and negative Eu anomalies, suggest that these intermediate igneous rocks were generated by partial melting of amphibolitic lower crust at a crustal depth of 30–40 km. The rhyolites have heterogeneous isotopic compositions, with ϵ Hf ( t ) values and T DM2 ages of –20.8 to +0.5 and 3578∼1494 Ma, implying that they were likely derived from partial melting of a mixed source dominated by recycled ancient crust with minor juvenile crustal materials. The rhyolites show potassic affinity with relatively high K 2 O and very low Na 2 O, which was attributed to liquid immiscibility of felsic magma and subsequent limited fractional crystallization of plagioclase. The regional igneous associations, metamorphic events, and coeval sedimentary rocks along the Solonker–Changchun suture zone indicate that the early Permian igneous rocks were formed in an active continental arc environment in response to southward subduction of the eastern Palaeo-Asian Ocean.
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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：
3
作者：
Pei‐yuan Hu;Cai Li;Ming Wang;Chao-Ming Xie;Yan-wang Wu
通讯作者：
Pei‐yuan Hu;Cai Li;Ming Wang;Chao-Ming Xie;Yan-wang Wu
影响因子：
3.9
作者：
Yongsheng Liu;Xiaohong Wang;Dong-bing Wang;Detao He;K. Zong;Changgui Gao;Zhaochu Hu;H. Gong
通讯作者：
Yongsheng Liu;Xiaohong Wang;Dong-bing Wang;Detao He;K. Zong;Changgui Gao;Zhaochu Hu;H. Gong
佳木斯和松嫩-张广才岭地块的汇聚历史：中国东北依兰黑龙江杂岩碎屑锆石 U-Pb 年代学的见解
影响因子：
6.1
作者：
Dong Yu;Ge Wenchun;Yang Hao;Ji Zheng;He Yue;Zhao Di;Xu Wenliang
通讯作者：
Xu Wenliang
影响因子：
12.1
作者：
Jian‐Bo Zhou;S. Wilde;Guochun Zhao;Jie Han
通讯作者：
Jian‐Bo Zhou;S. Wilde;Guochun Zhao;Jie Han