Abstract Myanmar, the third largest global tin supplier, is an important component of the Southeast Asian tin province. We have conducted laser ablation-inductively coupled plasma-mass spectrometry U-Pb dating of cassiterite, wolframite, and zircon and Re-Os dating of molybdenite from six primary and two placer Sn deposits in Myanmar. A combination of our geochronological data with previous studies revealed that three episodes of Sn mineralization in the Western tin belt of Southeast Asia formed during the closure of multiple Tethys oceans, namely the Late Triassic (~218 Ma) mineralization in a collisional setting after closure of the Paleo-Tethys, the Early Cretaceous (~124–107 Ma) mineralization during subduction of the Meso-Tethys, and the Late Cretaceous to Eocene (~90–42 Ma) mineralization related to the Neo-Tethys subduction. Recurrent Sn mineralization is recorded not only in the Western tin belt but also in the Central and Eastern tin belts in Southeast Asia. Compilation of currently available cassiterite U-Pb ages from all over the world revealed that durations of regional Sn mineralization events are typically in the range of ~5–30 m.y., whereas the Neo-Tethys subduction in Southeast Asia generated prolonged Sn mineralization lasting up to ~50 m.y. The Southeast Asian tin province, as a whole, has the longest cumulative episodes of mineralization, compared to other Sn provinces. The Sn mineralization ceased in the late Eocene when the tectonic setting changed from Neo-Tethys subduction to dextral motion along a series of strike-slip faults and extrusion of the Indochina block in Southeast Asia.

中文翻译：

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缅甸 Sn 矿化的年代学：成矿意义

摘要 缅甸是全球第三大锡供应国，是东南亚锡业省的重要组成部分。我们对缅甸六个原生锡矿和两个砂矿锡矿的锡石、黑钨矿和锆石进行了激光烧蚀-电感耦合等离子体-质谱法 U-Pb 测年和辉钼矿的 Re-Os 测年。我们的地质年代学数据与之前的研究相结合，表明东南亚西部锡带的三期 Sn 矿化是在多个特提斯洋关闭期间形成的，即晚三叠世（~218 Ma）在古特提斯，中特提斯俯冲期间的早白垩世（~124-107 Ma）矿化，以及与新特提斯俯冲相关的晚白垩世至始新世（~90-42 Ma）矿化。不仅在西部锡带，而且在东南亚的中部和东部锡带也有反复出现的 Sn 矿化。对来自世界各地的现有锡石 U-Pb 年龄的汇编表明，区域 Sn 矿化事件的持续时间通常在 ~5-30 my 范围内，而东南亚的新特提斯俯冲作用产生了持续时间长达~50 my 与其他锡省份相比，整个东南亚锡省份的矿化累积事件最长。晚始新世，当构造背景从新特提斯俯冲转变为沿东南亚印度支那地块的一系列走滑断层和挤压的右旋运动时，锡矿化停止。