扬子地块北缘秋树坪金矿锆石U-Pb测年及成矿流体特征研究
发布时间:2018-04-22 08:24
本文选题:秋树坪金矿 + U-Pb定年 ; 参考:《矿物岩石》2017年04期
【摘要】:秋树坪金矿位于杨子地块北缘汉南-米仓山隆起的汉南推覆隆起带。在矿区内采集含金石英脉样品一件,运用ICP-MS U-Pb锆石测年方法,获得热液锆石的加权平均年龄为90.2 Ma±1.5 Ma,为金矿的成矿年龄。含金石英脉内继承锆石年龄为1 160 Ma±33 Ma,1 746 Ma±23 Ma,与基底火地垭群火山岩年龄相近。采集不同成矿阶段的含金石英脉样品6件,进行成矿流体特征研究。流体包裹体测温研究,获得秋树坪矿床成矿热液温度为205.06℃~444.9℃、盐度为2.88%~7.38%,密度为0.56g/cm3~0.87g/cm~3,具中-高温、低盐度、低密度特征。通过激光拉曼光谱分析,流体包裹体气相成分主要由CH_4,CO_2,H_2S,H_2和N_2组成,液相成分主要为H_2O,CH_4和CO_2;含金石英脉氢氧同位素分析,δ~(18)O_水变化范围为3.11‰~15.42‰,δD值为-62.4‰~-84.2‰,认为原始成矿热液为变质热液,后期混入大气降水,使δ~(18)O_水值大幅下降。结合成矿流体特征与陆陆碰撞造山运动的构造背景,认为秋树坪金矿为该地区首次厘定的燕山期造山型金矿。
[Abstract]:Qiusuping gold deposit is located in the Hannan-Micang mountain uplift in the northern margin of Yangzi block. Using ICP-MS U-Pb zircon dating method, the weighted mean age of hydrothermal zircon is 90.2 Ma 卤1.5 Ma, which is the metallogenic age of gold deposit. The age of inherited zircon in gold-bearing quartz vein is 1 160 卤33 Ma 卤1 746 Ma 卤23 Ma, which is similar to that of volcanic rocks in Huodiya Group, basement. Six samples of gold-bearing quartz veins at different metallogenic stages were collected and the characteristics of ore-forming fluids were studied. The study of fluid inclusion temperature shows that the ore-forming hydrothermal temperature of Qiusuping deposit is 205.06 鈩,
本文编号:1786360
本文链接:https://www.wllwen.com/kejilunwen/kuangye/1786360.html