江西省朱溪钨(铜)多金属矿床流体包裹体及H-O同位素特征  

Characteristics of Fluid Inclusions and Hydrogen-Oxygen Isotopes in the Zhuxi W-Cu Polymetallic Deposit,Jiangxi Province

作　　者：李岩 潘小菲[2] 欧阳永棚[3] 饶剑峰 赵苗 张天福 LI Yan;PAN Xiaofei;OUYANG Yongpeng;RAO Jianfeng;ZHAO Miao;ZHANG Tianfu(Research Institute of Mineral Resources,China Metallurgical Geology Bureau,Beijing 101300;Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037;912 Geological Team,Bureau of Geology and Mineral Resources of Jiangxi Province,Yingtan,Jiangxi 335001;Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037;Tianjin Center of China Geological Survey,Tianjin 300170)

机构地区：[1]中国冶金地质总局矿产资源研究院,北京101300 [2]中国地质科学院地质研究所,北京100037 [3]江西省地质矿产勘查开发局912大队,江西鹰潭335001 [4]中国地质科学院矿产资源研究所,北京100037 [5]中国地质调查局天津地质调查中心,天津300170

出　　处：《地质与勘探》2020年第2期315-327,共13页Geology and Exploration

基　　金：深地项目国家重点研发计划项目(编号:2016YFC0600207);国家科技支撑计划项目(编号:2011BAB04B02)联合资助。

摘　　要：为了探讨江西朱溪钨多金属矿床的成矿流体性质及演化特征,本文对不同成矿阶段的矿石矿物和脉石矿物开展了流体包裹体以及H-O同位素研究。流体包裹体显微测温结果显示,该矿床矽卡岩期矿物流体包裹体的均一温度范围为231~358℃,盐度范围为3.87%~5.86%NaCl eqv,氧化物期和石英硫化物期矿物流体包裹体温度范围分别为167~403℃和114~351℃,盐度范围分别为1.57%~6.45%NaCl eqv和0.88%~8.00%NaCl eqv。激光拉曼探针测试表明,朱溪钨矿床流体包裹体组分主要为H 2 O,此外还含有少量CH 4、N 2和C 2 H 4。石英H-O同位素结果显示,δD v-SMOW值变化范围为-53‰^-87‰,δ18 O H 2O值介于2.58‰~5.68‰。自成矿早期到晚期,该矿床总体呈现缓慢降温的演化过程,钨在进入流体相后很可能以钨杂酸的络合物形式迁移,含钨的流体与碳酸盐岩围岩发生反应而引发流体酸碱度的变化,或后期大气水的加入导致的温度降低可能是朱溪钨矿床中钨沉淀成矿的主要机制。This work studied the properties and evolution of mineralization fluid in the Zhuxi W-Cu ploymetallic deposit,Jiangxi Province.The inclusions and H-O isotopes in ore and vein minerals in every mineralization stages were examined.Measurements by micro thermometry show that the homogenization temperature and salinity of the fluid inclusions in the skarn stage range in 231~358℃and 0.35%~5.26%NaCl eqv,respectively,while the temperature in the oxide stage and quartz sulfide stage varies from 167℃to 403℃and 114℃to 351℃,the salinity varies from 1.57%to 6.45%NaCl eqv and 0.88%to 8.00%NaCl eqv,respectively.Raman microspectroscopic tests of the fluid inclusions show that the main component is H 2 O,containing a certain amount of CH 4,N 2 and C 2 H 4.Analysis of H-O isotopes indicates thatδD v-SMOW varies from-53‰to-87‰,δ18 O H 2O varies from 2.58‰to 5.68‰.From the early to the late mineralization stages,a slow cooling process might have occurred in the deposit.Very likely the tungsten might migrate as a form of complex of tungstenic acid after becoming fluid,and the reaction of W-bearing fluid with carbonate country rock led to variation of the pH value in the fluid.And the temperature decrease caused by the atmospheric water added in the later period might be main mechanism of tungsten precipitation mineralization of the Zhuxi deposit.

关 键 词：流体包裹体 氢氧同位素 矽卡岩 朱溪钨矿 江西省 

分 类 号：P611.13[天文地球—矿床学] P597.2[天文地球—地质学]