摘要
云南马关都龙锡锌多金属矿床是我国最大的锡石硫化物矿床之一。都龙矿区绿泥石分布广泛,与成矿关系密切。本文对矿区铜街—曼家寨矿段中部F;断层不同深度的绿泥石进行了电子探针主量元素以及LA-ICPMS微量元素分析。结果表明,根据矿石类型、矿物组合不同,矿区绿泥石可分为3类。第1类绿泥石(Chl-Ⅰ)产于矽卡岩型矿石中,常与黑云母、闪锌矿和石英共生;第2类绿泥石(Chl-Ⅱ)产于石英萤石脉内,常与锡石密切共生;第3类绿泥石(Chl-Ⅲ)产于碳酸盐型矿石,常与方解石和闪锌矿密切共生。垂向上至下而上具有从Chl-Ⅰ→Chl-Ⅱ→Chl-Ⅲ分带的特点,这3类绿泥石均为三八面体结构富铁-镁种属绿泥石,暗示其形成于较还原的环境。Mg;与Fe;替代以及Tschermark替代是矿区绿泥石中主量元素替代方式。绿泥石地质温度计计算结果为203~289℃,表明成矿作用发生在中低温环境,3类绿泥石温度从Chl-Ⅰ至Chl-Ⅲ温度逐渐降低。结合其产出特征,推测这3类绿泥石可能是岩浆热液成矿过程不同阶段的产物。3类绿泥石中,随着与隐伏岩体的距离增加,Ca、Mn、Sr含量逐渐升高,而Sc、Ti、Ga逐渐降低,这可能与热液流体运移过程温度变化以及与围岩水岩反应有关。这些特征元素含量的变化具有指示绿泥石形成与岩体远近关系的潜力,深入研究绿泥石微量元素在矿区空间上的分布规律对深部探矿找矿工作具有重要的指导意义。
The Dulong Sn-Zn polymetallic deposit,located in Maguan County,Yunnan Province,is one of the largest Sn-polymetallic deposits in China.In the Dulong ore district,chlorite is widely distributed and is closely related to the tin mineralization.In this paper,the major elements and trace elements of chlorites at different depths of the F;fault in the central part of the Tongjie-Manjiazhai ore block have been analyzed by using EPMA and LA-ICPMS.Based on different ore types and mineral assemblages of the Dulong deposit,the chlorite can be classified into three types.The first type of chlorite (Chl-Ⅰ) occurs in skarn ores and is often co-existed with biotite,sphalerite,and quartz;The second type of chlorite(Chl-Ⅱ) occurs in quartz-fluorite veins and is often closely associated with cassiterite;The third type of chlorite (Chl-Ⅲ)occurs in carbonate type ores and is often closely associated with calcite and sphalerite;Three types of chlorites are distributed at a vertical profile from the bottom to the top with the chlorite zones varying from the Chl-Ⅰ,to the Chl-Ⅱ,to the Chl-Ⅲ subsequently.The Dulong chlorites are all Fe-rich or Mg-rich chlorites with trioctahedral structure,indicating that they were formed in a relatively reduced environment.The substitution mechanisms of major elements in the Dulong chlorite are mainly represented by the Fe;-Mg;and Tschermark substitutions.The calculated results using the chlorite geothermometer range from 203℃to 289℃,indicating that the mineralization occurred under a medium-low temperature condition.From the Chl-Ⅰ to the Chl-Ⅱ,to the Chl-Ⅲ,their temperatures are gradually decreased,suggesting that these three types of chlorites could represent products of different stages of the magmatic hydrothermal mineralization.With the increase of distance away from the concealed granite,the Ca,Mn,and S contents of these three types of chlorites are gradually increased,while their Sc,Ti,and Ga contents are gradually decreased.This may be related to the temperature change of
作者
刘仕玉
刘玉平
叶霖
韦晨
陈威鸿
胡宇思
LIU Shi-yu;LIU Yu-ping;YE Lin;WEI Chen;CHEN Wei-hong;HU Yu-si(State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academic of Science,Guiyang 550081,China;University of the Chinese Academy of Sciences,Beijing 100049,China)
出处
《矿物学报》
CAS
CSCD
北大核心
2022年第1期1-13,共13页
Acta Mineralogica Sinica
基金
云南华联锌铟股份有限公司科研项目(编号:ZY-201807-03)
贵州省自然科学基金(编号:黔科合基础-ZK[2021]213)。
