作　　者： ; ; ; ; ; ; ;

机构地区： 中国地质大学北京地球科学与资源学院地质过程与矿产资源国家重点实验室

出　　处： 《岩石学报》 2013年第4期1203-1213,共11页

摘　　要： 云南香格里拉县红山铜矿是三江义敦岛弧带南端重要铜矿床,颇受关注,成因认识分歧大。矿区出露上三叠统板岩、变碎屑岩和灰岩夹中基性火山岩、火山碎屑岩以及少量侵入其中的中酸性和超基性岩脉、岩株,透镜状铜硫化物矿体产在顺层状矽卡岩体内或边部,成矿后断裂明显。矿石中普遍发育以黄铁矿为核部、黄铜矿为中间带、磁黄铁矿为边部带的硫化物环带,其中核部黄铁矿呈立方体自形-半自形晶,黄铜矿呈他形晶围绕黄铁矿沉淀,磁黄铁矿呈他形分布在黄铜矿外围,内带常被外带硫化物溶蚀交代。环带从内到外硫化物先后沉淀,矿物生成顺序为黄铁矿-黄铜矿-磁黄铁矿。环带中三种硫化物矿物的REE配分曲线和微量元素蛛网图极为相似,负Eu异常显著,富集U、Th、Zr、Hf,亏损Rb、Sr、Ba,与矿区超基性岩表现出较高相似性;环带从内到外,∑REE(0.17371×10-6、1.22626×10-6、5.25925×10-6)和微量元素含量依次升高,Co/Ni和Se/Te比值降低,指示矿石硫化物沉淀过程中,可能伴随热液体系内地壳物质不断增加。环带中硫化物矿物δ34SV-CDT=3.81‰～5.23‰,具有岩浆硫源特征,δ34SV-CDT边部带磁黄铁矿(4.47‰)<δ34SV-CDT中间带黄铜矿(4.58‰)<δ34SV-CDT核部黄铁矿(4.65‰),三种硫化物间没有达到同位素平衡分馏。红山铜矿石环带结构是岩浆热液为主成矿流体中黄铁矿、黄铜矿、磁黄铁矿先后晶出成因,伴随硫化物环带的形成,热液系统从早到晚H2S和O2逸度降低或pH升高过程。 The Hongshan copper deposit, located in Shangri-la, Yunnan, China, is tectonically situated in the southern part of Sanjiang Tethyan Zhongdian island arc. It is one of the most significant deposits in this district and gets very popular concerned since its discovery with hotly debated about the genesis. It occurs slate, metaclastics and limestone interbedding with medium-basic volcanic rock and volcanoclastic rock and intruded by intermediate-acidity and ultrabasic dykes or stocks. Lenticular copper sulfide ore-bodies occur in bedded skarn bodies or adjacent to it, and is disrupted by post-metallogenic faults. The copper ores develop sulfide zonal texture with pyrite as nuclear, chalcopyrite as intermediate zone and pyrrhotite as external zone. Pyrite in the core is usually euhedral or subhedral crystal while the coating chalcopyrite and pyrrhotite are anhedral. Chalcopyrite precipitate around the early-formed pyrite, pyrrhotite which acted as the main body of the sulfide zonal texture grows around the chalcopyrite. The inner sulfide is generally replaced by the outer one. The sulfide zonal texture precipitates from the inside out as the following order： pyrite-chalcopyrite-pyrrhotite. Analysis of trace elements and S isotopes exhibit similar characteristics from different sulfides of the zonal texture, for example, moderate REE and strong Eu depletion with a gentle seagull REE pattern; riched in HFSE as U, Th, Zr, Hf and depleted in LILE as Rb, Sr and Ba; both the REE and TE distribution patterns of sulfides are similar to those of ultrabasic rocks in Hongshan area; whereas from nuclear pyrite to intermediate chalcopyrite and to external pyrrhotite, the total trace elements and REEs （∑REE 0.17371×10-6, 1.22626×10-6 and 5.25925×10-6） shows gradually increasing meanwhile Co/Ni and Se/Te gradually decreasing pattern. The above features indicate the mineralizing fluid trapping more crustal component during evolution. The δ34SV-CDT of 24 sulfides have a magmatic feature ranging from 3.81‰ and 5.23‰, a

关 键 词： 硫化物环带 微量元素 硫同位素 红山铜矿 云南香格里拉

领　　域： [天文地球] [天文地球] [天文地球] [天文地球]