沉积与特提斯地质2024，Vol.44Issue(2)：411-420,10.DOI:10.19826/j.cnki.1009-3850.2023.09002
缅甸Wunto-Popa岩浆弧Shangalon铜金矿床辉钼矿Re-Os同位素测年及其地质意义
Re-Os isotope dating of molybdenite from Shangalon Cu-Au deposit in the Wunto-Popa magmatic arc,Myanmar and its geological significance
摘要
Abstract
The Shangalon copper-gold deposit is located in the northern segment of the Wunto-Popa magmatic arc in Myanmar.The research on this deposit is limited,and there is a lack of high-precision isotopic geochronological data regarding its ore-forming geological background and deposit genesis.In this study,five molybdenite samples from typical ores were selected to determine the mineralization age using the Re-Os isochron dating method.The obtained model ages range from 38.3±0.6 to 38.5±0.5 million years ago(Ma),with a weighted average age of 38.4±0.2 Ma.The corresponding isochron age is 38.0±1.6 Ma(MSWD=0.17).Both ages are in good agreement within the error range,indicating that the mineralization timing of the Shangalon copper-gold deposit is in the Eocene epoch.This age data corresponds well with the zircon U-Pb ages of 38 to 40 million years for the mineralized syenogranite and granodiorite in the mining area,suggesting a close relationship between the Shangalon Cu-Au-Mo mineralization and Eocene syenogranite-granodiorite intrusions,which are products of Eocene magmatic activity.The Re contents of molybdenite samples from the Shangalon copper-gold deposit range from 82.4 to 111.2 µg·g-1,with an average value of 98.88 µg·g-1,indicating a mixed source from the crust and mantle for the mineralizing fluids.Based on a comprehensive analysis of the regional metallogenic dynamics,it is suggested that the Eocene copper-gold mineralization in the Shangalon region possibly formed as a result of the fragmentation and faulting of the Neo-Tethys oceanic plate,triggered by the collision between the Indian and Eurasian continents,leading to upwelling of the asthenosphere and partial melting of the lower crust.关键词
辉钼矿/Re-Os同位素定年/Shangalon铜金矿床/Wunto-Popa岩浆弧/缅甸Key words
molybdnite/Re-Os isotopic ages/Shangalon Cu-Au deposit/Wunto-Popa magmatic arc/Myanmar分类
天文与地球科学引用本文复制引用
冷秋锋,吴松洋,刘书生,聂飞,张彬..缅甸Wunto-Popa岩浆弧Shangalon铜金矿床辉钼矿Re-Os同位素测年及其地质意义[J].沉积与特提斯地质,2024,44(2):411-420,10.基金项目
国家自然科学基金重点基金(92055314) （92055314）
东南亚和南亚国际合作地质调查(DD20230127) （DD20230127）
四川省"天府万人计划"杰出科学家项目(川万人第 023号) （川万人第 023号）
云南省科学技术奖-杰出贡献奖项目(2017001) （2017001）
