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黑尖山Fe-Cu(-Au)矿床位于新疆东天山阿齐山-雅满苏岛弧带。黑尖山矿体赋存于上石炭统马头滩组火山岩和火山碎屑岩中。根据脉体穿切关系和矿物共生组合类型,可将黑尖山的矿物生成顺序划分为7个阶段,分别为铬铁矿阶段(Ⅰ)、绿帘石蚀变阶段(Ⅱ)、磁铁矿阶段(Ⅲ)、黄铁矿阶段(Ⅳ)、铜(金)阶段(Ⅴ)、后期脉阶段(Ⅵ)和表生蚀变阶段(Ⅶ)。阶段Ⅰ以在磁铁矿的核部出现铬铁矿为特征;阶段Ⅱ主要为绿帘石化;阶段Ⅲ为Fe矿化,以磁铁矿与角闪石共生为主,伴有少量钾长石化;阶段Ⅳ以石英-黄铁矿-磁黄铁矿±黄铜矿为共生矿物组合;阶段Ⅴ为Cu(-Au)矿化,以石英-黄铜矿-赤铁矿和黄铜矿-银金矿-绿泥石脉为特征;阶段Ⅵ主要为后期的热液脉体;阶段Ⅶ主要出现一些铜的表生矿物。磁铁矿阶段(Ⅲ)和铜(金)阶段(Ⅴ)分别为黑尖山的Fe和Cu(-Au)矿化阶段。H、O同位素研究结果显示:黑尖山在Fe矿化之前,大量晚石炭世海水与黑尖山矿区围岩在基性岩浆所产生的区域热作用下发生反应,形成大面积的绿帘石蚀变(阶段Ⅱ:δ18Ofluid=6.3‰~7.8‰,δDfluid=-12.3‰~-7.3‰);Fe矿化主要受高温(约590℃)的岩浆热液控制(阶段Ⅲ磁铁矿、石英和阳起石的δ~(18)Ofluid分别为8.8‰,9.5‰~9.7‰和8.9‰~9.3‰;阳起石的δD_(fluid)=-102.5‰~-87.6‰),并受其他因素(围岩及围岩中残留海水和有机质)的影响;外来的低温盆地卤水可能是形成硫化物和Cu(-Au)矿化的主要控制因素;后期大气降水的加入与大量后期热液脉体的形成相关(阶段Ⅵ:δ18Ofluid=1.4‰~3.5‰;δD_(fluid)=-76.1‰~-57.2‰)。黑尖山Fe-Cu(-Au)矿床在蚀变、矿化共生组合和成矿流体来源等方面与安第斯中生代IOCG型矿床相似,且黑尖山矿床Fe和Cu(-Au)矿化阶段成矿流体的显著不同可能是东天山阿齐山-雅满苏岛弧带其他Fe-Cu矿床的普遍特征,从而区别于典型矽卡岩型和海相火山岩型矿床。
The Black Jianshan Fe-Cu (-Au) deposit is located in the Azimut-Yaman Su island arc belt of the East Tianshan, Xinjiang. Black tip mountain ore body occurs in Upper Carboniferous Matoutan Formation volcanic rocks and pyroclastic rocks. According to the relationship between vein-type cuttings and mineral assemblages, the sequence of mineral formation in Mount Blackwater can be divided into seven stages: chromite stage (Ⅰ), epidotis alteration stage (Ⅱ), magnetite stage (Ⅲ), pyrite phase (Ⅳ), copper (gold) phase (Ⅴ), late pulse phase (Ⅵ) and epigenetic alteration (Ⅶ). Stage I is characterized by the presence of chromite in the core of magnetite; stage I is mainly epidote; stage III is Fe mineralization with the coexistence of magnetite and amphibole together with a small amount of potassium feldspar ; Stage IV quartz - pyrite - pyrrhotite ± chalcopyrite as a symbiotic mineral combination; Stage V Cu (-Au) mineralization, quartz - chalcopyrite - hematite and chalcopyrite - silver Gold ores - chlorite veins; stage Ⅵ mainly for the late hydrothermal veins; stage Ⅶ mainly copper epigenetic minerals. The magnetite stage (Ⅲ) and the copper (gold) stage (Ⅴ) are the Fe and Cu (-Au) mineralization stages of Mount Blackhead, respectively. H and O isotope studies show that before the Fe mineralization, a large amount of Late Carboniferous seawater reacted with the surrounding rock of the Blackjianshan deposit in the region of the basaltic magma to form a large-scale green-curtain alteration (Stage II: δ18Ofluid = 6.3 ‰ ~ 7.8 ‰, δDfluid = -12.3 ‰ ~ -7.3 ‰); Fe mineralization is mainly controlled by magmatic hydrothermal fluids of high temperature (about 590 ° C) (Stage Ⅲ magnetite, quartz, The δ 18 O of the rocks is 8.8 ‰, 9.5 ‰ ~ 9.7 ‰ and 8.9 ‰ ~ 9.3 ‰, respectively. The δD fluid of the rock is from 102.5 ‰ to -87.6 ‰, and is influenced by other factors And the residual seawater and organic matter in the surrounding rock). The brine from low-temperature basins may be the main controlling factor for the formation of sulfide and Cu-Cu mineralization. The addition of later-stage precipitation is related to the formation of a large number of late-forming hydrothermal veins (Stage VI: δ18Ofluid = 1.4 ‰ ~ 3.5 ‰; δD_ (fluid) = -76.1 ‰ ~ -57.2 ‰). The Heijianshan Fe-Cu (-Au) deposit is similar to the Andean Mesozoic IOCG deposit in terms of alteration, mineralization and mineralization, and the ore-forming fluids of the Fe and Cu (-Au) mineralization stages of the Blackjianshan deposit The significant difference may be the general characteristics of the other Fe-Cu deposits in the Aqishan-Yaman Su Island arc belt in the East Tianshan, which is different from the typical skarn-type and marine volcanic-type deposits.