矿床地质2024，Vol.43Issue(1)：102-127,26.DOI:10.16111/j.0258-7106.2024.01.007
瑶岗仙花岗质岩浆演化与两类钨矿化成因关系研究:黑云母和石榴子石矿物化学证据
Genesis relationship between magma evolution and two types of tungsten mine-ralization in Yaogangxian deposit:Evidence from biotite and garnet chemistry
摘要
Abstract
The Yaogangxian W deposit in the Nanling region hosts quartz vein-type wolframite orebody and skarn-type scheelite orebody,which both reach large scale sizes and together to make this deposit to be one of the largest W deposits around the world.Both quartz-vein-and skarn-type orebodies occur in the contact zones between the Yaogangxian granitic complex and the country rocks.The Yaogangxian complex massif mainly consists of medi-um-grained biotite monzogranite and fine-grained two-mica monzogranite,but the genetic relationship between multi-stage magmatic evolution and different types of tungsten mineralization has been debated intensively.In this study,we examined the geochemical characteristics of biotite and garnet from the medium-grained biotite monzogranite and fine-grained two-mica monzogranite,in order to figure out chemical conditions during the for-mation of different granitic phases.Biotite from the fine-grained two-mica monzogranite has lower XMg value,closer to Fe2+ end members,lowerⅣ(F)and higher log(f HF/f HCl)fluid value than that from the medium-grained bi-otite monzogranite,indicating that the former formed in more reduced environment with higher F contents com-pared to the latter.Garnet from both phases are typical magmatic origin,and are in spessartite compositions.MnO contents in garnet grains increase with the decrease of CaO,FeO,and MgO contents,and Mn/(Mn+Fe)values,and Sc,Zn,Y,and HREE concentrations gradually increase with the decrease of MgO contents from medium-grained biotite monzogranite to fine-grained two-mica monzogranite,suggesting that the magmatic differentiation of fine-grained two-mica monzogranite is higher than that of medium-grained biotite monzogranite,which is con-ducive to the enrichment of W.The formation of quartz vein-type wolframite and skarn-type scheelite ores are proposed to be characterised by low oxygen fugacity and high F content,which is consistent with that of the fine-grained two-mica monzogranite.Accordingly,in combination of the geophysical,geochemical,and drilling infor-mation,we propose the exploration model for the deep part of the Yaogangxian deposit,and define quartz vein-type wolframite prospecting target in the deep Dagenlong area,greisen-type W prospecting target in the deep Yan-meiling area,and skarn-type scheelite prospecting target in the southeast of the Heshangtan area.关键词
黑云母/石榴子石/氧逸度/挥发分/结晶分异/勘查模型/瑶岗仙钨矿Key words
biotite/garnet/oxygen fugacity/volatiles/fractional crystallization/exploration model/Yao-gangxian W deposit分类
天文与地球科学引用本文复制引用
郭聪,赵正,刘战庆,吴小辉,刘洋..瑶岗仙花岗质岩浆演化与两类钨矿化成因关系研究:黑云母和石榴子石矿物化学证据[J].矿床地质,2024,43(1):102-127,26.基金项目
本文得到国家自然科学基金地质联合基金重点项目(编号:U2344207)、国家重点研发计划项目(编号:2022YFC2905101)、国家自然科学基金(编号:41973046)、中国地质调查局地质调查项目(编号:DD20190713)联合资助 （编号:U2344207）
