摘要
广东玉水铜矿是一个以斑铜矿、黄铜矿为主的高品位铜矿床,主矿体呈层状沿中石炭统白云岩/下石炭统石英砂岩界面产出。本文在详细的野外地质工作基础上,确认了块状矿体下盘存在石炭纪凝灰岩、火山丘状体及火山通道;确认了以红色赤铁矿-菱铁矿-碧玉岩为组合的喷气沉积岩,其稳定覆盖在块状矿层的顶部,并延伸出矿体外围。层状矿体层序由下往上为:(含砾)石英砂岩夹凝灰岩→块状铜铅锌硫化物矿层→赤铁矿-菱铁矿-碧玉岩等喷气沉积岩→白云岩,证实含矿岩系具有火山岩—矿体—喷气岩“三位一体”特征。层状矿体具有典型的“双层”结构:上部为块状矿体;下部为筒状含矿蚀变体,由呈漏斗状的流体通道系统及其浸染状、网脉状矿化体组成。围绕主流体通道发育扇形含硫化物石英细脉,且不穿过上覆块状矿体和上盘白云岩。本文还首次报道了控制矿体和凝灰岩厚度及铜矿体塑性流变的同生断层(同火山断层)。综合矿床地质及地球化学研究表明玉水铜矿是形成于浅海环境下的喷流沉积块状硫化物矿床。这一新认识表明VMS型矿床可以形成于浅海水环境下,这对丰富和完善VMS型矿床的成因模式具有重要的科学价值;同时可为华南寻找类似地质背景区的隐伏VMS型铜多金属矿床提供借鉴。
The Yushui deposit is a high-grade copper(bornite and chalcopyrite)deposit with main orebodies occurring between the dolomite of the Upper Carboniferous and quartz sandstone of Lower Carboniferous.The detailed field geological survey confirmed the existence of Carboniferous tuff in the footwall of the massive orebodies,and newly discovered volcanic mounds and volcanic conduits and vents.We also confirmed that the red hematite-siderite-jasperite combination is an exhalative-sedimentary rock,which covers the top of the massive orebodies and extends well beyond the margins of massive sulfide.Therefore,the sequence of the stratiform orebody is determined from bottom to top:quartz(gravelbearing)sandstone interbedded with tuff→massive copper-lead-zinc sulfide orebody→hematite-sideritejasperite and other exhalative-sedimentary rocks→dolomite,showing that the ore-bearing rock series has the characteristics of“trinity”:volcanic rocks-massive orebody-exhalite combination.The stratiform orebodies show typical“double-layer”structure:the upper part is a massive orebody,and the lower part is a cylindrical ore-bearing alteration body,which composed of a funnel-shaped fluid conduit system and its disseminated and network mineralization.Fan-shaped sulfide-containing quartz veins are developed around the main fluid conduit,and do not cut through the overlying massive orebody and dolomite of hanging wall.Synsedimentary faults(synvolcanic faults)that control the thickness of the orebody and tuff and the plastic flow of the copper orebodies have been newly discovered.The above geological evidence demonstrates that the Yushui deposit is a submarine exhalative sedimentation massive sulfide deposit which formed in shallow water environments.This conclusion will inspire VMS deposit studies,has important scientific value globally,and can be used as a reference for prospecting for concealed VMS copper polymetallic deposits in similar geological background areas in South China.
作者
陈懋弘
柯昌辉
田永飞
陈港
马克忠
马收先
彭永新
张威
CHEN Maohong;KE Changhui;TIAN Yongfei;CHEN Gang;MA Kezhong;MA Shouxian;PENG Yongxin;ZHANG Wei(MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,CAGS,Beijing 100037,China;Yushui Sulfur-copper Mining of Jinyan Industry Group Co.,Ltd,Meizhou,Guangdong 514200,China)
出处
《地质学报》
EI
CAS
CSCD
北大核心
2021年第6期1774-1791,共18页
Acta Geologica Sinica
基金
中国地质调查局地质调查二级项目(编号DD20201173)
广东金雁工业集团有限公司玉水硫铜矿委托科研项目《广东梅州玉水铜矿矿床成因及成矿预测研究》资助的成果。
关键词
石炭纪火山岩
流体通道
同生断层(同火山断层)
浅海VMS型矿床
广东玉水铜矿
Carboniferous volcanic rocks
fluid conduit
synsedimentary fault(synvolcanic faults)
shallow marine VMS deposits
Yushui copper deposit
