投稿时间：2015-03-26
修订日期：2016-05-16
网络发布日期：2016-06-30
中文摘要:柿竹园W-Sn-Mo-Bi-Pb-Zn-Ag矿田是南岭地区典型多金属矿田,其具有显著的蚀变-成矿分带特征:近接触带矽卡岩-云英岩型W-Sn-Mo-Bi矿床(如柿竹园、金船塘、柴山地区)和远接触带脉状Pb-Zn-Ag矿床(如蛇形坪、横山岭、百步窿、枞树板地区)。通过对远-近接触带中主要蚀变岩石和矿石样品的C、H、O、Pb同位素研究,发现在近接触带块状矽卡岩中方解石的δ13C和δ18O值分别在-6.5‰~-3.6‰和4.8‰~8.4‰之间,远接触带Pb-Zn-Ag矿脉中团块状和脉状方解石的δ13C和δ18O值分别在-3.5‰~-1.5‰和8.1‰~15.8‰之间,表明矽卡岩形成于岩浆热液流体的渗滤交代作用,而远接触带碳酸盐脉的形成与热液流体沿灰岩裂隙充填过程中的水岩反应相关。近接触带块状云英岩中石英的δDH2O和δ18OH2O值分别为-77‰和5.1‰,矽卡岩中石榴子石的δDH2O值为-97‰,δ18OH2O值范围在9.2‰~9.4‰,网脉状云英岩中石英的δDH2O和δ18OH2O值分别为-83‰和-8.2‰,退化蚀变矽卡岩中石英的δDH2O和δ18OH2O值分别为-65‰和-4.2‰,远接触带石英脉中石英样品的δDH2O和δ18OH2O值分别为-83‰和2.8‰,表明近接触带的块状矽卡岩和云英岩与远接触带石英脉成矿流体具有岩浆水的特征,而网脉状云英岩和退化蚀变矽卡岩成矿流体具有岩浆流体与大气水混合的特征。远-近接触带中方铅矿的 206Pb/204Pb 值范围18.565~18.622, 207Pb/204Pb 值范围15.694~15.738, 208Pb/204Pb 值范围38.819~38.986,表明Pb等金属元素来源于上地壳。
中文关键词:地球化学 W-Sn-Mo-Bi矿床 Pb-Zn-Ag矿床 稳定同位素 柿竹园
Abstract:The Shizhuyuan W-Sn-Mo-Bi-Pb-Zn-Ag orefield is one of the typical polymetallic orefields in Nanling region and shows significant alteration and mineralization zonation for proximal skarn-greisen W-Sn-Mo-Bi deposits (such as Shizhuyuan, Jinchuantang, and Chaishan) and distal veined Pb-Zn-Ag deposits (such as Shexingping, Hengshanling, Baibulong, and Congshuban). The authors carried out C-O-H-Pb isotopic analysis of the alteration rocks and ores from proximal-distal mineralization areas. The δ13C and δ18O values of calcites from the proximal skarns are between -6.5‰ and -3.6‰ and between 4.8‰ and 8.4‰, respectively, and those from the distal Pb-Zn-Ag range from -3.5‰ to -1.5‰ and from 8.1‰ to 15.8‰, respectively, which suggests that skarn was formed by the infiltration metasomatism and distal carbonate veins were derived from water/rock reactions with limestone. The δDH2O and δ18OH2O values of quartz from proximal greisens are -77‰ and 5.1‰, respectively, δDH2O values of garnets from proximal skarns are -97‰, while δ18OH2O values of them range between 9.2‰ and 9.4‰, the δDH2O and δ18OH2O values of quartz from stockwork greisens are -83‰ and -8.2‰, respectively, the δDH2O and δ18OH2O values of quartz from retrograde skarns are -65‰ and -4.2‰, respectively, and the δDH2O and δ18OH2O values of quartz from distal quartz veins are -83‰ and 2.8‰. It is thus concluded that the hydrothermal fluids forming proximal skarn-greisen and distal quartz veins were probably magmatic water, while the fluids forming stockwork greisens and retrograde skarns were mixtures of magmatic and meteoric water. The 206Pb/204Pb values of galena from proximal-distal mineralization areas are between 18.565 and 18.622, 207Pb/204Pb between 15.694 and 15.738, and 208Pb/204Pb between 38.819 and 38.986, which confirm that ore-forming elements were mainly derived from the upper crust.
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中图分类号：P618.67
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基金项目:本文得到国家自然科学基金项目(编号:41303034、41430314)和中国地质调查局地质调查工作项目(编号:12120113093600)联合资助
引用文本：
吴胜华,戴盼,王旭东.2016.柿竹园钨多金属矽卡岩-云英岩与铅锌银矿脉C、H、O、Pb同位素地球化学研究[J].矿床地质,35(3):633~647WU ShengHua,DAI Pan,WANG XuDong.2016.C, H, O, Pb isotopic geochemistry of W polymetallic skarn-greisen and Pb-Zn-Ag veins in Shizhuyuan orefield, Hunan Province[J].Mineral Deposits35(3):633~647
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