西天山智博铁矿床黄铁矿成分特征及硫同位素研究  

Chemical composition and sulfur isotope of pyrite from Zhibo iron ore deposit in Western Tianshan Mountains

作　　者：王志华[1] 侯岚[1] 高永伟[1] 张振亮[1] 蒋宗胜[2] 张作衡 WANG ZhiHua;HOU Lan;GAO YongWei;ZHANG ZhenLiang;JIANG ZongSheng;ZHANG ZuoHeng(Xi’an Center of Geological Survey,CGS,Xi’an 710054,Shaanxi,China;MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;China Geological Survey,Beijing 100037,China)

机构地区：[1]自然资源部岩浆作用成矿与找矿重点实验室中国地质调查局西安地质调查中心,陕西西安710054 [2]中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室,北京100037 [3]中国地质调查局,北京100037

出　　处：《矿床地质》2018年第6期1319-1336,共18页Mineral Deposits

基　　金：国家自然科学青年基金(编号:41402079;41602096;41502088);国土资源部公益性行业科研专项课题(编号:201211073-02);国家重点基础研究发展计划(编号:2012CB416803)联合资助

摘　　要：智博大型磁铁矿床位于新疆西天山阿吾拉勒铁铜成矿带东段,主要矿石矿物为磁铁矿,主要共生金属矿物为黄铁矿。文章通过对黄铁矿进行矿物成因研究来推测矿床成因及特征。本次研究选择2个成矿期的矿石及围岩中的黄铁矿进行电子探针及硫同位素研究。电子探针数据显示岩浆期黄铁矿w(Co)平均为4703×10^(-6),大于热液期w(Co)(735.71×10^(-6)),Co/Ni比值(平均18.53)也大于热液期黄铁矿Co/Ni比值(平均0.96);S/Se比值多数集中于1000～8000之间。部分Co/Ni、Se/Te、S/Se比值落入热液成因范围内,暗示了热液流体参与成矿的可能性。而Co-Co/Ni图解显示岩浆期矿石和热液期矿石具有一定的继承性。黄铁矿中δ^(34)S值介于-1.2‰和0.3‰之间,表明硫主要来源于幔源硫。智博铁矿床矿石主要为岩浆成因,但岩浆期后热液及其他热液流体也参与了晚阶段的成矿作用。The Zhibo iron deposit is located in the eastern section of the Awulale iron metallogenic belt in Western Tianshan Mountains,Xinjiang.Magnetite is the major ore mineral and pyrite is the major associated metal mineral.In this paper,the genesis and characteristics of the iron deposit are inferred by studying the genesis of pyrite.The pyrite in ores of two metallogenic periods and surrounding rock was chosen to be studied by electron microprobe and sulfur isotope analysis in this study.EPMA data show that the average Co content(4703×10^-6)of pyrite from the magmatic phase in the Zhibo mining area is higher than that of the hydrothermal phase(735.71×10^-6),and the Co/Ni ratio(average18.53)is also higher than that of hydrothermal period(average0.96).The S/Se ratio of pyrite is mainly concentrated in the range of1000~8000.Partial Co/Ni,Se/Te and S/Se ratios fall within the hydrothermal origin,suggesting the possibility of hydrothermal fluids participating in ore formation.The Co-Co/Ni diagram indicates that the ore from the magmatic phase and hydrothermal phase probably have certain inheritance.The value ofδ^34S in pyrite is between-1.2‰and0.3‰,indicating that sulfur mainly originated from magmatic sulfur.The authors hold that the ore of Zhibo iron deposit was mainly of magma origin,however,the postmagmatic hydrothermal and other hydrothermal fluids also participated in the late stage of mineralization.

关 键 词：地球化学 黄铁矿 成分特征 硫同位素 智博铁矿 

分 类 号：P618.31[天文地球—矿床学]