摘要
赣南安前滩钨矿是于都-赣县钨多金属矿集区的重要组成部分,主要成矿类型为石英脉型黑钨矿和矽卡岩型白钨矿.采用电子探针对二云母花岗岩、含钨矿石英脉和矽卡岩进行岩相学观察和矿物成分分析,并通过显微测温和激光拉曼光谱对黑钨矿及共生石英中包裹体进行研究.结果表明,二云母花岗岩至少在岩浆晚期或岩浆-热液过渡阶段就发生了以含钨金红石和白钨矿为代表的钨初步富集;花岗岩演化晚期含F,CO2等挥发分的流体有利于钨的运移和富集,周围钙质围岩和断裂构造控制着含矿矽卡岩的展布;含矿石英脉中黑钨矿包裹体均一温度和盐度(262~375℃,5.56 wt.%~11.10 wt.%NaCleqv.)普遍高于共生石英(165~253℃,1.74 wt.%~10.73 wt.%NaCleqv.),表明在安前滩中-高温、中-低盐度流体体系下,黑钨矿的沉淀早于共生石英,流体混合作用可能是黑钨矿沉淀的主要机制.
Anqiantan tungsten deposit,as one of tungsten polymetallic deposits in the Yudu-Ganxian metallogenetic belt in southern Jiangxi Province,comprises quartz-vein type wolframite and skarn type scheelite mineralizations.Petrographical,mineralogical and fluid inclusion studies on two-mica granite,W-bearing quartz vein and skarn were conducted by electron probe micro-analyzer(EPMA),microthermometry and laser Raman spectrum analysis.Results show that the tungsten was initially enriched in late magmatic or magmatic-hydrothermal stage of two-mica granite,forming Nb-W-bearing rutile and scheelite.The F,CO2 and volatiles-bearing fluid exsoluted from granite plays an important role in tungsten transportation and precipitation.Ca-bearing wall-rocks and the faults nearby control the distribution of skarns in the Anqiantan tungsten deposit.In wolframite-quartz vein,the homogenization temperatures and salinities for primary inclusions in wolframite(262~375℃,5.56%~11.10% NaCleqv.)are generally higher than those in quartz(165~253℃,1.74%~10.73% NaCleqv.).These studies imply that wolframite formed earlier than coexisting quartz in the fluid system with medium-high temperature,and low-medium salinity.The fluid mixing is probably the principal tungsten depositional mechanim.
作者
邬斌
王汝成
李光来
廖益萱
Wu Bin;Wang Rucheng;Li Guanglai;Liao Yixuan(State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang,330013,China;School of Earth and Space Sciences,Peking University,Beijing,100871,China;School of Earth Sciences and Engineering,Nanjing University,Nanjing,210023,China)
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第6期788-799,共12页
Journal of Nanjing University（Natural Science）
基金
国家自然科学基金(41702033,41862008,41862004)
南京大学内生金属矿床成矿机制研究国家重点实验室开放基金(2017-LAMD-K07)
东华理工大学博士启动基金(DHBK2016124)
核资源与环境国家重点实验室自主基金(Z1907)联合资助。
关键词
高分异花岗岩
安前滩钨矿
黑钨矿
热液矿床
流体包裹体
highly fractionated granite
the Anqiantan tungsten deposit
wolframite
hydrothermal deposit
fluid inclusion
