滇西北衙超大型斑岩-矽卡岩-浅成低温热液成矿系统关键金属及其成因分析

作为高新产业重要原材料的关键金属，在地壳内平均含量低和分布不均匀，使得其优势矿床类型尚不清晰，尤其是多类型多金属的共存储库—斑岩-矽卡岩-浅成低温热液成矿系统内共(伴)生的关键金属值得深入关注。北衙多金属矿是金沙江-哀牢山成矿带内与喜山期富碱斑岩有关的斑岩型铜金钼-矽卡岩型铁金铜-浅成低温热液型铅锌银金复合成矿系统。在系统梳理前人有关主体金属矿物原位微量元素研究的基础上，本次研究初步查明共伴生的关键金属包括四种：(1) Re：赋存于斑岩型和矽卡岩型矿化的辉钼矿中，含量为2.51×10^-6～62.64×10^-6;(2) Co：以类质同象替代形式赋存于矽卡岩型矿化的磁铁矿中，含量为0.13×10^-6～41.1×10^-6;(3) Bi：以铋化物形式赋存于斑岩型和矽卡岩型矿化中，包括铋铅矿、Bi-Cu硫盐、Bi-Pb硫盐、Bi-Ag硫盐、Bi-Cu-Pb硫盐、Bi-Pb-Ag硫盐和含Bi硫族化合物，其中辉铋矿是主要含铋矿物；(4) Te：赋存于斑岩型、矽卡岩型和浅成低温热液型矿化的硫化物(碲含量：80×10...

Key metals in the Beiya giant porphyry-skarn-epithermal metallogenic system of western Yunnan Province and their genesis

Key metals are important raw materials to support the development of high-tech industries. Due to their low average and uneven distribution in the crust, their metallogenesis remains unclear. Porphyry-skarn-epithermal polymetallic mineralization systems, as the coexistence reservoir of multi-types of mineralization and metals, is worth paying more attention to the key metals of it. The Beiya gold polymetallic deposit is a significant metallogenic system, from porphyry Cu-Au-Mo mineralization through skarn Fe-Au-Cu mineralization to epithermal Pb-Zn-Ag(Au) mineralization, which was related to the Himalayan alkali-rich porphyry in the Jinshajiang-Ailaoshan metallogenic belt. Based on previous mineral insitu trace-element studies on the main metals, the associated key metals are divided into four types: (1) Re: occurs in the molybdenite of porphyry and skarn mineralization, with a content of 2.51×10-6 ~62.64×10-6 . (2) Co: occurs in the magnetite of skarn mineralization, with a content of 0.13×10-6 ~ 41.1×10-6 . (3) Bi: occurs in the bismuth minerals of the porphyry and skarn mineralization, including bismuth-lead mineral, Bi-Cu sulfosalt, Bi-Pb sulfosalt, Bi-Ag sulfosalt, Bi-Cu-Pb sulfosalt, Bi-Pb-Ag sulfosalt and Bi-bearing sulfides, of which the bismuthinite is the dominated Bi-bearing mineral. (4) Te: occurs in the sulfides (Te: 80×10-6 ~390 ×10-6 ) or telluride of porphyry, skarn and epithermal mineralization. The telluride minerals include tsumoite, joseite, volynskite, tetradymite and so on. Combined with previous geological and geochemical studies, it is inferred that the enrichment of key metals (Re, Co, Bi, and Te) in the Beiya polymetallic deposit was associated with the strong crust-mantle interaction in the deep part of the Jinshajiang-Ailaoshan metallogenic belt, which was under the post-collisional dynamic background of the Cenozoic India and Asian continental plates.