西藏雄村矿区1号矿体黄铁矿标型特征及其地质意义  

Typomorphic characteristics and geological significance of pyrite from No.1 deposit in the Xiongcun district,Tibet

作　　者：吴昌益 郎兴海[1] 张赫 王旭辉[1] 张鹏 邓煜霖 娄渝明 姜楷 WU Chang-yi;LANG Xing-hai;ZHANG He;WANG Xu-hui;ZHANG Peng;DENG Yu-lin;LOU Yu-ming;JIANG Kai(College of Earth Science,Chengdu University of Technology,Chengdu 610059,China;Sichuan Academy of Land Science and Technology,Chengdu 610074,China;Tibet Tianyuan Minerals Exploration Ltd.,Xigaze Tibet 857000,China)

机构地区：[1]成都理工大学地球科学学院,成都610059 [2]四川省国土科学技术研究院,成都610074 [3]西藏天圆矿业资源开发有限公司,西藏日喀则857000

出　　处：《矿物岩石地球化学通报》2024年第2期372-386,共15页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家重点研发计划项目(2022YFC2905002);国家自然科学基金资助项目(41972084,42230813);中国地质调查局地质调查项目(KD-[2023]-XZ-013)。

摘　　要：为研究西藏雄村矿区黄铁矿的成因矿物学和找矿矿物学意义,本文对雄村矿区1号矿体主成矿阶段的黄铁矿开展了X射线衍射、热电性、电子探针和LA-ICP-MS分析。结果表明,1号矿体黄铁矿晶胞参数a0为5.41438×10^(-10)~5.41966×10^(-10)m,平均Δa0值为5.41747×10^(-10)m;体积V为158.7190×10^(-10)~159.1946×10^(-10)m^(3),ΔV平均值为158.9896×10^(-10)m^(3);热电系数α为-336.7~330.6μV/oC。黄铁矿S含量为51.34%~53.44%,平均值为52.92%;Fe含量为44.06%~46.90%,平均值为46.18%,Co/Ni值集中在10附近。结合前人研究成果,我们认为1号矿体主成矿阶段的黄铁矿为岩浆热液成因,主要为N型黄铁矿,形成于硫逸度较低的中高温环境。另外,黄铁矿不是1号矿体的主要载金矿物,预测该矿体处于成矿系统的中下部,在深部具有一定的延伸趋势,但是很可能被后期侵位的黑云母花岗闪长岩破坏,深部找矿潜力不大。In order to study the genetic mineralogy and prospecting significance of pyrites in the Xiongcun deposit in Tibet,the thermoelectric analysis,X-ray fluorescence diffraction analysis,electron microprobe analysis,and LA-ICP-MS analysis of pyrites from the No.1 orebody of the Xiongcun deposit have been carried out in this paper.The results display that pyrites in the No.1 orebody of the deposit have unit cell parameters varying form 5.41438×10^(-10) m to 5.41966×10^(-10) m(average 5.41747×10^(-10) m),volumes varying form 158.7190×10^(-10) m3 to 159.1946×10^(-10) m^(3)(with the average ΔV of 158.9896×10^(-10) m^(3)),thermoelectric coefficients varying form-336.7 to 330.6μV/℃,S contents of 51.34%~53.44%(average of 52.92%),Fe contents of 44.06%~46.90%(average of 46.18%),and Co/Ni ratios of about 10.Combined with previous research results,it is believed that pyrites of the main mineralization stage in the No.1 orebody mainly belong to the N-type pyrite.They are of magmatic hydrothermal origin and were formed in the medium to high temperature environment with relatively low sulfur fugacity.In addition,the pyrite is not the main gold-bearing mineral in the No.1 orebody.It is predicted that the No.1 orebody is in the middle-lower part of the original oreforming system.There could be a certain extension trend of the orebody in the depth.However,the deep part of No.1 orebody was more likely to have been destroyed by the later emplaced biotite granodiorite.Therefore,there is a relatively low prospecting potential of mineral resources in the depth of No.1 orebody.

关 键 词：西藏雄村矿区 黄铁矿 晶胞参数 热电性 斑岩型矿床 

分 类 号：P578.292[天文地球—矿物学]