摘要
广西丹池成矿带五圩矿田三排洞矿床由早期Sb-Au矿化和晚期Pb-Zn-Sb矿化组成,而五圩矿田其它矿床则仅见Pb-Zn-Sb矿化。本文对比分析了三排洞矿床两类矿化控矿构造产状、包裹体均一温度、盐度、气液相组成、矿物组合、闪锌矿铁含量等差异,探讨两类矿化成因联系,论证其是否为复合成矿作用形成的矿床。早期Sb-Au矿化主要产于走向320°断裂带中,矿体倾向NE,倾角50°~60°,主要由辉锑矿、雄雌黄、辰砂及自然金组成(Au>2×10-6),银含量低(<20×10-6);Pb-ZnSb矿化产于走向350°断裂带中,矿脉倾向SWW,倾角70°~80°,主要由闪锌矿、脆硫锑铅矿、特硫锑铅矿、硫锑铅矿等组成,富银(>100×10-6),贫金(<0.1×10-6)。早期和晚期矿化脉中流体包裹体温度峰值分别在160~200℃和180~230℃之间,富CO_2包裹体数占总包裹体数分别约为8%和45%;早期和晚期矿化闪锌矿Fe含量分别为小于0.12%和在1.40%~3.65%之间;早期矿化锑矿物主要为辉锑矿,晚期矿化锑矿物则主要为脆硫锑铅矿、特硫锑铅矿及硫锑铅矿。上述差异表明早期矿化成矿热液具Sb-Au-As-Hg元素组合,相对贫CO_2及Fe,而晚期矿化成矿流体具Pb-Zn-Sb-Ag元素组合,富CO_2及Fe。据五圩矿田其它Pb-Zn-Sb矿床未发生Au成矿作用、三排洞矿床两期矿化受控于不同产状断裂构造、晚期矿化成矿温度高于早期矿化成矿温度、两期矿化成矿热液元素组成尤其是Au和Ag含量及CO_2含量的明显差异等,可以认为三排洞矿床早期Sb-Au和晚期Pb-Zn-Sb矿化为不同成矿作用的产物,两者没有成因联系,三排洞矿床发生了复合成矿作用。同一矿区不同成矿作用可形成不同元素组合矿体。
The Sanpaidong polymetal deposit in the Danchi ore zone consists of Pb-Zn-Sb and Sb-Au ore bodies. Here the faults controlling occurrences of ore bodies,homogeneity temperature,salinity and gas composition of fluid inclusions,iron content in sphalerite,mineral assemblage of the two different types of mineralization are comparative analyzed to elucidate if the two different types of mineralization are genetic related or not. The Sb-Au mineralization which was cut through by the Pb-Zn-Sb mineralization occurs in the faults striking 320° and dipping NE with angles varying from 50° - 60°,while the Pb-Zn-Sb mineralization was controlled by faults striking 350° and dipping SWW with angles about 70° - 80°. The primary fluid inclusions in quartz from the early stage Sb-Au mineralization have peak value interval of homogenization temperature varying from 160 - 200℃,with salinity in the main range of 3. 5% - 5. 5% NaCleqv,while the primary fluid inclusions in sphalerite from the late stage of Pb-Zn-Sb mineralization have the peak value interval of homogenization temperature varying from 180℃ to 230℃ with salinity in the range of 8% - 10% NaCleqv. The ore forming fluid of the early stage Sb-Au mineralization is poor in CO2,while the ore forming fluid of the second stage Pb-Zn-Sb mineralization rich in CO2; Sphalerite from the early and late stage mineralization has Fe content less than 0. 12% and in the range of 1. 4% - 3. 65%,respectively,suggesting that the late stage mineralization of ore forming fluids contain high concentration of iron given their mineralization temperature is similar to each other. The early and late stage antimony minerals differ greatly from each other,antimony mineral of early stage mineralization is mainly stibnite,while the late stage jamesonite,twinnite and boulangerite,suggesting that the early and late stage main mineralization were formed in different geochemical environment. The above differences between the early and late stage mineralization in Fe content in sphalerite,gas comp
作者
伍静
农仕华
黄文婷
张健
梁华英
苑金涛
陈玲
WU Jing;NONG ShiHua;HUANG WenTing;ZHANG Jian;LIANG HuaYing;YUAN JinTao;Chen Ling(College of Resource, Environment and Materials, Guangxi University, Nanning 530004, China;Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Gaangzhou 510640, China;University of Chinese Academy of Sciences, Beijing 100049, China;Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Qinzhou College, Qinzhou 535011, China)
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2018年第5期1327-1334,共8页
Acta Petrologica Sinica
基金
"973"项目(2015CB452602)
国家自然科学基金项目(41772065
41421062)联合资助
