藏南扎西康Pb-Zn-Sb-Ag多金属矿床典型矿物标型研究  

A Study on the Typomorphic Characteristics of Typical Mineral from Zhaxikang Pb-Zn-Sb-Ag Polymetallic Deposit in Southern Tibet

作　　者：代鸿章[1] 程文斌[2] 李关清[1,3] 陈翠华[2] 张兴国 朱黎宽[4] 

机构地区：[1]地质过程与矿产资源国家重点实验室中国地质大学(北京)地球科学与资源学院,北京100083 [2]成都理工大学地球科学学院,四川成都610059 [3]西藏地勘局区域地质调查大队,西藏拉萨850004 [4]中国地质科学院郑州矿产综合利用研究所,河南郑州450006

出　　处：《矿物学报》2014年第1期72-82,共11页Acta Mineralogica Sinica

基　　金：西藏自治区矿产资源潜力评价项目(编号:1212010813025);国家自然科学基金项目(批准号:41171302);教育部高校博士点基金项目(编号:20125122120013);高等教育质量工程项目<矿相学>优秀教材建设(编号:XJC1105)

摘　　要：扎西康矿床地处雅鲁藏布江缝合带(ITS)与主边界逆冲断层(MBT)之间,是藏南Au-Sb成矿带内以富含硫盐矿物为特征的Pb-Zn-Sb-Ag多金属矿床。通过对该矿床典型硫化物热电系数、晶胞参数及化学成分等标型特征的研究,得到黄铁矿导电类型以P型为主,α值介于17.4~384.6μV/℃之间,占总数的92%;所有方铅矿导电类型为N型,热电系数变化范围为-372.1^-419.9μV/℃。黄铁矿晶胞参数a介于0.54195~0.54239 nm,As置换S是其增大的主要因素;闪锌矿a值为0.54111~0.54210 nm,Fe、Cd进入闪锌矿使其晶胞参数增大;方铅矿中普遍含Ag而使晶胞参数低于理论值。黄铁矿、闪锌矿、方铅矿等矿物化学成分标型均指示地层为矿源层,成矿过程与热液改造作用紧密相关;银矿物及硫盐矿物多以微细连晶形式产出,反映成矿的多阶段性。综合分析认为扎西康Pb-Zn-Sb-Ag矿床为多期次多阶段中低温热液改造型矿床。Zhaxikang Pb-Zn-Sb-Ag polymetallic deposit located in southern Tibet metallogenic belt between the ITS and MBT is rich in sulfosalt minerals. In this paper, we studied some research on the typomorphic characteristics of pyrite including thermoelectric coefficients, cell parameters and chemical composition. The results are as follows. Firstly, the main conductivity type of pyrite is N type accounting for 92% and the values of a are between 17.4 μV/℃ and 384.6 μV/℃. All the galenas show N type with values of ct ranging from -372.1 μV/℃ to -419.9μV/℃.Secondly, the crystal parameter of pyrites （0.54195- 0.54239 m） are higher than theoretical value for As displaced S. The value of sphalerite＇ a （0.54111-0.54210 nm） are also higher because of Fe and Cd fixed into the sphalerite crystal texture, however, galena is generally lower than the theoretical value for containing Ag. Therefore, these dates above indicates that the forming of the deposit is related to the hydrothermal deformation and controlled by the layer which is acted as the source beds. Silver mineral and sulfosalt mineral occur in the form of fined joined crystal showing the different stages. All these reveals Zhaxikang Pb-Zn-Sb-Ag polymetallic deposit is formed in mid-low temperature hydrothermal deformation experiencing different stages.

关 键 词：扎西康Pb-Zn-Sb-Ag多金属矿床 典型硫化物 标型特征 矿床成因 

分 类 号：P571[天文地球—矿物学] P611.1[天文地球—地质学]