吉林小西南岔金铜矿床流体包裹体及成矿作用研究  

A STUDY OF FLUID INCLUSlONS AND ORE-FORMINGPROCESS OF THE XIAOXINANCHA GOLD-COPPERDEPOSIT, JILIN PROVINCE

作　　者：李荫清[1] 陈殿芬[1] 

机构地区：[1]中国地质科学院矿床地质研究所

出　　处：《矿床地质》1995年第2期151-173,T001,共24页Mineral Deposits

基　　金：国家自然科学基金

摘　　要：该矿床流体包裹体丰富，为２相气液、１相液体、少数含子晶多相和含液态ＣＯ＿２三相包裹体。包裹体液相中富Ｎａ￣＋、Ｃｌ￣－和ＳＯ，气相中Ｈ＿２Ｏ占优势，ＣＯ＿２次之。属ＮａＣｌ－Ｈ＿２Ｏ体系。包裹体同位素分析表明，成矿流体为岩浆水和大气降水的混合流体。在温度高于３６０～４００℃的中性—弱酸性热流体中，Ａｕ和Ｃｕ的络合物呈迁移状态，在温度低的弱酸—酸性的较还原环境下，围岩产生广泛的石英－绢云母化，导致Ａｕ、Ｃｕ络合物分解，沉淀出大量Ａｕ和Ｃｕ。The Xiaoxinancha large-size gold-copper deposit is located inside northeast HunchunCounty at the eastenmost end of Jilin Province, lying in Tumenjiang delta zone. The ore de-posit occurs on the western limb of the nearly SW-trending Wudao syncline, with the hostrocks being metamorphic rocks of the Lower Paleozoic Qinglongcun Group. Gold and coppermineralizations are closely related to the concealed early Yanshanian granite porphyry in thisarea. The orebody consists of gold- and copper-bearing quartz veins which fill the NNW-trending fissures as well as veinlet-disseminated mineralized bodies on their both sides. Its totalNNW-striking length is some 2. 5 km, its width is 0.8 km, and the downward extensionreaches 100￣700m.The ore deposit contains abundant fluid inclusions, which are mainly two phase gas-liquidand one phase liquid inclusions and , next , polyphase inclusions that contain daughter crystals ,with a few two phase gas-rich inclusions and three phase inclusions that contain liquid CO_2.The principal gold and copper mineralization stage is dominated by the first two types. Themost striking character of the fluid composition is that in cations , Na￣+ is most numerous and inanions, Cl￣- is slightly more than SO. In gas phase, H_2O is dominant, followed .by CO_2.Ore-forming fluids are basically of the NaCl-H￣2O system. δD values of inclusions vary in therange of -51‰ ￣80‰, and δ￣(18)O_(H_2O) in the range of + 0. 1 3‰￣+5. 61‰, falling into the re-gion between the magmatic water and the meteoric water line.δ￣(13)C_(co_2) values of CO_2 gas in in-clusions are 0. 5‰￣ -6. 8‰ , exhibiting character of deep carbon. All these data demon-strate that the ore-forming fluids are mixed fluids of magniatic hydrothermal solution derivedfrom the depth and meteoric water.At the early stage of the ore-forming process,magmatic hydrothermal solution played aleading role. When temperature was higher than 500℃. fluids reacted with wall rocks at thetop of the porphyry body and the contact zone

关 键 词：金矿床 铜矿床 液包体 成矿作用 

分 类 号：P618.510.4[天文地球—矿床学] P618.410.4[天文地球—地质学]