摘要
云南会泽铅锌矿床是扬子块西南缘川―滇―黔接壤区的铅锌银多金属矿集区已探明的唯一超大型铅锌矿床,矿床规模大(Pb+Zn探明储量超过500万吨)、品位高(Pb+Zn平均品位大于25%)、伴生元素多(Ag、Ge、Cd、Ga等),有很高的研究和经济价值。本文在总结该矿床地质特征、成矿流体性质及来源基础上,探讨了成矿流体迁移和沉淀机制。研究表明,低温(150～200℃)条件下,Zn主要以硫氢化物络合物迁移,少量呈氯化物络合物形式;Pb主要以氯化物络合物,少量以硫氢化物络合物形式进行迁移;高温(300～400℃)条件下,Pb、Zn主要以氯化物络合物的形式进行迁移。流体混合作用导致成矿流体温度降低,还原硫和Cl-浓度降低,pH值升高和氧逸度降低是成矿元素沉淀的主要机制。
The Huize Pb-Zn deposit in Yunnan Province,China,is the only super-large Pb-Zn deposit ascertained in Sichuan-Yunnan-Guizhou Pb-Zn-Ag polymetallic ore concentration area on the southwestern margin of the Yangtze Block.With the feature of large-scale（the proved reserves of Pb＋Zn is over 5.0 million tons）,high-grade（the average grade of Pb and Zn in ore deposit is higher than 25%）,and many kinds of associated elements（Ag,Ge,Cd,and Ga）,it has important research and economic value.In this study,we discusses the mechanism of transportation and precipitation of the ore-forming fluid by using thermodynamics combine with previous studies on geological characteristics and source and characteristics of ore-forming fluids of Huize Pb-Zn deposit.At low temperatures（150–250 ℃）,Zn transported mainly as hydrosulfide complex and only a few as chloride complex.While,Pb transported mainly as chloride complex and a few as hydrosulfide complex;At middle and high temperatures（300–400 ℃）,Pb and Zn both transported mainly as chloride complex.The main precipitation mechanism of mineralization elements is fluid mixing which causes the decrease of temperature of ore-forming fluid,concentration of reduced sulfur and Cl-,oxygen fugacity and the increase of pH.
出处
《矿物学报》
CAS
CSCD
北大核心
2012年第2期288-293,共6页
Acta Mineralogica Sinica
基金
中国科学院重要方向项目(KZCX2-YW-Q04-05)
“973”计划项目(2007CB411402)
关键词
成矿物理化学条件
成矿元素迁移和沉淀
会泽超大型铅锌矿床
中国云南
metallogenic physicochemical condition
transportation
precipitation
mineralization element
Huizesuper-large Pb-Zn deposit
Yunnan
China
