投稿时间：2015-11-26
修订日期：2016-09-10
网络发布日期：2017-03-11
中文摘要:高通岭钼矿床位于海南岛中部的早白垩世-晚白垩世高通岭岩体中，是一个小型热液脉型钼矿床。作者对赋矿围岩黑云母钾长花岗岩进行了岩相学观察、LA-ICP-MS锆石U-Pb定年、锆石Lu-Hf同位素测试和锆石微量元素分析。结果显示：赋矿围岩矿物组合为钾长石（45%~60%）、石英（20%~30%）、斜长石（10%~20%）及黑云母（10%~15%）；矿石矿物以辉钼矿为主，矿石类型主要为石英脉型，次为蚀变黑云母钾长花岗岩型和碎裂岩型；高通岭岩体中的锆石，具有清晰的振荡环带，显示其岩浆成因；锆石U-Pb年代学研究获得206U/238Pb加权平均年龄为（102.5±1.8）Ma，锆石的176Hf/177Hf比值为0.282 349~0.282 663，εHf（t）为-12.8~-1.7，二阶段地壳模式年龄（TDMC）为1976~1271 Ma，峰值为1450~1400 Ma，锆石稀土元素配分模式显示高通岭岩体的陆壳源区属性。地表取样的黑云母钾长花岗岩（GTL-03和GTL-04）具有较低Ce4+/Ce3+比值（160左右），反映了较低氧逸度，钻孔取样的黑云母钾长花岗岩具有较高Ce4+/Ce3+比值（平均值377）。高通岭岩体总体上氧逸度较低，暗示其大规模成矿潜力较低。
中文关键词:地球化学 锆石U-Pb定年 Hf同位素 Ce4+/Ce3+比值 高通岭钼矿床
Abstract:The Gaotongling molybdenum ore deposit classified as the quartz vein type ore deposit is located in the central area of the Hainan Island. It is hosted in the Cretaceous granite named Gaotongling terrace. In order to investigate mineral composition, metallogenic age and metallogenic source of the Gaotongling molybdenum deposit, the authors conducted petrographic observations, LA-ICP-MS zircon U-Pb dating, zircon in situ Lu-Hf isotope analysis and trace elements analysis of the ore-hosting rocks. The ore-hosting rocks are medium-coarse grained biotite moyite, and the ore types can be divided into quartz vein type molybdenite ore, altered moyite type molybdenite ore and cataclastic rock type molybdenite ore. LA-ICP-MS zircon dating of biotite moyite rock yielded 206U/238Pb ages varying from 105.10 Ma to 99.89 Ma with weighted average age of (102.5±1.8) Ma. LA-ICP-MS zircon Hf isotopic analyses show εHf(t) values of biotite moyite rocks from -12.8 to -1.7. The two-stage crust model ages (TDMC) of Gaotongling terrace vary from 1976 Ma to 1271 Ma, with the peaks from 1450 Ma to 1400 Ma. Combined with REE characteristics of zircons, the authors hold that the Gaotongling rocks belong to continental crust. Early Gaotongling granite rocks have low Ce4+/Ce3+ ratios (around 160), reflecting a low oxygen fugacity, whereas Gaotongling granite samples collected from the drill hole have high Ce4+/Ce3+ ratios (377 on average), showing a higher oxygen fugacity. Gaotongling granites possess confined metallogenic capacity.
文章编号：
中图分类号：P618.65
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基金项目:本文受到国家重点研发计划"深地资源勘查开采"（编号：2016YFC0600401）重点专项和国土资源部全国矿产资源潜力评价项目（编号：1212010881625）资助
引用文本：
朱昱桦,于亮亮,于得水,许德如,付王伟.2017.海南岛高通岭钼矿床赋矿岩体LA-ICP-MS锆石U-Pb年龄、Hf同位素和Ce4+/Ce3+特征[J].矿床地质,36(1):185~199ZHU YuHua,YU LiangLiang,YU DeShui,XU DeRu,FU WangWei.2017.LA-ICP-MS zircon U-Pb dating, Hf isotopic composition and Ce4+/Ce3+ characteristics of Gaotongling molybdenum ore deposit in Hainan Province and their implications for metallogeny[J].Mineral Deposits36(1):185~199
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