中文摘要:对采自西华山钨矿的大颗粒辉钼矿样品的不同部位进行了取样,并对 其年龄分别进行精确厘定,得到了不同的Re-Os模式年龄值,验证了失耦现象的存在。从原 理上对失耦现象及其成因进行了解释,并在前人成果的基础上,探索性地提出了187Os可能 的迁移模型。取样方式的不同会对辉钼矿的模式年龄产生很大影响,因此,在实际应用中一 定要严格遵循“多取样,细磨碎”的原则,这对于能获得科学真实的与地质背景相符的Re-O s同位素地质年龄,从而深入探讨矿床成矿作用具有重要意义。
Abstract:Different parts of coarse-grained molybdenite from the Xihuashan tungsten deposi t were sampled and dated, which yielded different Re-Os apparent ages and hence confirmed the decoupling of Re and 187Os within molybdenite. The decoupling phenomenon and its cause were explained, and a tentative migration model of 187Os within coarse-grained molybdenite was established. The results show that the difference in sampling methods might exert remarkable influence o n the Re_Os apparent age. In order to reduce the influence of decoupling on Re-O s dating, more molybdenite samples should be collected, and the samples should b e ground into homogeneous powder (200 meshes). Only in this way can scientific a nd accurate Re-Os ages be obtained.
keywords:geochemistry, Re-Os dating, decoupling, migration model, molybdenite, tungsten deposit, Xihuashan
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基金项目:国家科技支撑计划“南岭地区有色_贵重金属综合勘查技术研究”课题(2006BAB 01B03),中国地质大调查“我国重要矿产和区域成矿规律研究”项目(1212010633903), “中国成矿体系综合研究”项目(1212010634002)以及“我国西部重要成矿区带矿产资源 潜力评估” 项目(编号200420190004)
引用文本:
李 超,屈文俊,杜安道.2009.大颗粒辉钼矿Re-Os同位素失耦现象及187Os迁移模式研究[J].矿床地质,28(5):707~712.2009.Decoupling of Re and Os and migration model of 187Os in coarse-grained molybdenite [J].Mineral Deposits28(5):707~712
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