广西龙湾铅锌矿床矿石矿物组构特征及成矿阶段划分

通过井下的详细勘查和显微镜下鉴定,对广西龙湾铅锌矿床的矿石组构特征进行了系统研究.矿区矿石构造主要为块状构造、浸染状构造、网脉状构造和斑杂状构造;结构主要为结晶作用和交代作用形成的结构,其次为固溶体分离作用、结晶物质重结晶作用和压力作用形成的结构.同时将成矿期次分为沉积成岩期、中低温热液成矿期和表生氧化期,其中热液成矿期是矿床的主要成矿期.根据矿物组合特征,将成矿划分为五个成矿阶段,分别是黄铁矿-石英-方解石阶段、闪锌矿-方铅矿-黄铁矿阶段、黄铁矿-闪锌矿-方铅矿-黄铜矿阶段、石英-方解石阶段、氧化物阶段.矿物的生成顺序为黄铁矿1-闪锌矿(黄铜矿1)-方铅矿-黄铁矿2-黄铜矿2.最终确定龙湾矿床为受构造活动控制的中低温热液充填交代-叠生改造型多金属矿床.

Ore Minerals Fabric and Mineralization Stage Division of Pb-Zn Deposit in Longwan Guangxi

Ore-fabric characteristics of Pb-Zn deposit systematic study in Longwan,Guangxi by detailed exploration of mine and the microscopic identification. Ore structure is mainly massive structure,dissemination structure,stockwork structure and taxitic structure. The texture is mainly formed in metasomatism and crystallization ,secondly for solid solution separation,crystallized matter recrystallization and pressure effect. Mineralization periods into sedimentary diagenesis,in epithermal mineralization period and supergene oxidation stage,the hydrothermal mineralization period mainly is the deposit metallogenic period. According to the characters of mineral composition,the mineralization is divided into five stages of mineralization,which is pyrite-quartz-calcite stage,sphalerite-galena-pyrites stage, pyrite-sphalerite-galena-chalcopyrite stage,quartz-calcite stage,oxide stage.Mineral equence is pyrite 1-sphalerite （chalcopyrite1）-galena-pyrite 2-chalcopyrite2. It is determined that Longwan ore deposit is low-temperature hydrothermal filling account-storeyed reworked polymetallic deposits control by tectonic activity.