Tethyan suturing in Southeast Asia: Zircon U-Pb and Hf-O isotopic constraints from Myanmar ophiolites
Tethyan suturing in Southeast Asia: Zircon U-Pb and Hf-O isotopic constraints from Myanmar ophiolites
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东南亚特提斯缝合带：来自缅甸蛇绿岩的锆石 U-Pb 和 Hf-O 同位素约束
作者：
Yang Xu;Jian-Gang Wang;Yi Chen;Shun Guo
出现在东南亚的蛇颈龙代表了特提斯洋的遗迹，特提斯洋在中生代的大部分时间里存在于冈瓦纳大陆和劳亚大陆之间。缅甸的两条蛇绿岩带，东带和西带，传统上被认为是与青藏高原雅鲁藏布缝合带相连的单一缝合带的一部分，并被右行走的实皆市断裂所取代。本文首次对缅甸两条蛇绿岩--缅甸西部卡拉缪蛇绿岩和缅甸东部密支那蛇绿岩进行了锆石二次离子质谱U-Pb年龄和Hf-O同位素联合分析。研究结果表明，卡拉缪蛇绿岩的时代为早白垩世（约1000年）。与雅鲁藏布江缝合带的新特提斯蛇绿岩沿着。而密支那蛇绿岩则形成于中侏罗世（约1000年）。东带是中特提斯班公湖-怒江缝合带在青藏高原的南延。因此，我们认为，这两个缅甸蛇绿岩带属于两个不同的中特提斯和新特提斯缝合线，Sibumasu和缅甸西部之间的边界是一个侏罗纪缝合线，而不是一个横向剪切带。
Ophiolites that crop out in Southeast Asia represent the relics of the Tethys Ocean, which existed between the continents of Gondwana and Laurasia during much of the Mesozoic. Two ophiolite belts in Myanmar, i.e., the Eastern Belt and the Western Belt, have been conventionally regarded as parts of a single suture connecting with the Yarlung-Tsangpo suture in the Tibetan Plateau and displaced by the dextral Sagaing fault. Here we present for the first time a combined analysis of zircon secondary ion mass spectrometry U-Pb ages and Hf-O isotopes of two Myanmar ophiolites, the Kalaymyo ophiolite from the Western Belt and the Myitkyina ophiolite from the Eastern Belt. Our results show that the Kalaymyo ophiolite has an Early Cretaceous age (ca. 127 Ma), coeval with Neo-Tethyan ophiolites along the Yarlung-Tsangpo suture. In contrast, the Myitkyina ophiolite was formed during the Middle Jurassic (ca. 173 Ma) and thus the Eastern Belt is the southern continuation of the Meso-Tethyan Bangong-Nujiang suture in the Tibetan Plateau. Consequently, we argue that the two Myanmar ophiolite belts belong to two different sutures of the Meso-Tethys and Neo-Tethys, and that the boundary between the Sibumasu and west Burma blocks is a Jurassic suture rather than a transcurrent shear zone.
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西藏那曲蛇绿岩碳质球粒状地幔来源的骨同位素证据及其意义
影响因子：
--
作者：
LIU DeLiang;ZHANG XiaoRan;FAN ShuaiQuan;DING Lin
通讯作者：
DING Lin
影响因子：
2.7
作者：
A. Mitchell
通讯作者：
A. Mitchell
DOI：
10.1144/gsl.sp.1988.037.01.09
发表时间：
1988
期刊：
Geological Society, London, Special Publications
影响因子：
--
作者：
A. Şengör;D. Altıner;A. Cin;T. Ustaömer;K. Hsü
通讯作者：
A. Şengör;D. Altıner;A. Cin;T. Ustaömer;K. Hsü
影响因子：
3.1
作者：
J. Rubin;C. Henry;J. G. Price
通讯作者：
J. Rubin;C. Henry;J. G. Price
DOI：
--
发表时间：
2008
期刊：
Acta Geological Sinica
影响因子：
--
作者：
X. Bin
通讯作者：
X. Bin