西藏雄村铜金矿矿集区Ⅰ号矿体磁黄铁矿矿物特征及指示意义

Typomorphic Characteristics and Significance of Pyrrhotite in Xiongcun Cu-Au Deposit

雄村铜金矿是近年来西藏发现的又一大型斑岩铜金矿床,矿体中主要的金属矿物为黄铜矿、黄铁矿、磁黄铁矿、磁铁矿、方铅矿、闪锌矿。磁黄铁矿在矿石中含量较高,并常与黄铜矿紧密共生,电子探针分析结果表明,磁黄铁矿存在六方和单斜两种晶型,分析结果表明,雄村铜金矿矿物生成顺序为cp+py+mag→cp+py+pyr→py+sph+gal,成矿温度始于360℃,成矿系统温度下降缓慢,成矿时间较长。

Xiongcun Coper-gold deposit is one of the large porphyry copper-gold mines discovered in Tibet,with ore minerals including chalcopyrite,pyrite,pyrrhotite,magnetite,galena and sphalerite.The pyrrhotite is high in ore and usually accretes to chalcopyrite.It is indicated with the electron microprobe that the pyrrhotite has two crystal forms,hexagonal and monoclinic.The ore-forming sequence is following the order of cp＋py＋mag,cp＋py＋pyr and py＋sph＋gal.According to the result of micropobe analysis,the formational temperature is about 360 ℃ and then drops slowly,suggesting the long time of mineralization.