| 摘要: |
| 云南南角河银多金属矿床石英包裹体的均一温度为100~148℃,δDH2O值为-91.9‰~-69.0‰,δ18OH2O值为-15.60‰~-5.66‰,成矿流体主要来源于古大气降水,可能也混入少量岩浆水。矿石中δ34S值分布范围为-2.18‰~5.95‰,平均为2.15‰,偏离陨石硫的范围,而与基性岩类硫非常接近,矿石硫来源于深源热液流体。临沧花岗岩体铅同位素组成反映其来源的不均匀性和复杂性,包含有上地壳、下地壳及上地幔等组分。矿石铅同位素组成主要落入Zartman和Doe的铅构造模式造山带演化线附近及其上方,表明其来源为壳幔混合铅。矿石铅与临沧花岗岩体铅的对比显示,矿石铅组成由临沧花岗岩体混染澜沧群变质岩构成。 |
| 关键词: 银多金属矿 同位素 地球化学 南角河 云南 |
| DOI： |
| 附件 |
| 投稿时间：2002-12-30 |
| 基金项目: |
|
| Isotopic geochemistry of the Nanjiaohe silver polymetallic ore deposit in Yunnan |
| WANG Feng, JIN Jing-fu |
| (Department of Nuclear Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, China) |
| Abstract: |
| The study of isotopic geochemistry of the minerals from the Nanjiaohe silver polymetallic ore deposit in Yunnan shows that the quartz inclusions have the homogenization temperatures ranging from 100 to 148℃, δDH2O values ranging from -91.9 to -69.0‰, δ18O values ranging from -15.60 to -5.66‰. The ore-forming fluids are derived chiefly from fossil meteoric water, with a small amount of magmatic water. The ores have the δ34S values ranging from -2.18 to 5.95‰, with an average of 2.15‰, that is deviated from the fields of meteoritic sulphur but closer to those of the sulphur in basic rocks. The sulphur in the ores is originated from deep-seated hydrothermal fluids. The study of lead isotopic compositions indicates that the Lincang granite masses consist of the upper and lower crust and upper mantle material. The lead isotopic compositions in the ores fall mostly into or near the fields of the orogenic zones indicated by the model from Zartman and Doe, suggesting a mixed crust-mantle origin of lead. |
| Key words: silver polymetallic ore deposit isotope geochemistry Nanjiaohe Yunnan |
