贵州天柱云洞铅锌矿地质特征及成矿作用分析

Geological Characteristics and Mineralization Analysis of Yundong Lead-zinc Deposit in Tianzhu,Guizhou

云洞铅锌矿床位于南华裂谷盆地之雪峰次级裂谷盆地,赋矿地层为震旦系陡山沱组,容矿围岩主要为碳酸盐岩,少量为碎屑沉积岩,矿体呈层状、似层状产出,矿物以闪锌矿、黄铁矿及少量方铅矿,矿石结构主要有晶粒、交代残余结构,矿石构造主要为星点状、条纹状、角砾状、细粒浸染状、脉状,围岩蚀变为碳酸盐化、硅化、重晶石化。硫同位素为δ^(34) S在+13.5‰-+22.9‰之间,碳同位素为δ^(13) C_(PDB)=-4.7‰--8.42‰之间;氧同位素为δ^(13)O_(PDB)=-13.31‰--14.64‰,成矿温度142℃-255℃,属中低温成矿流体,铅锌矿床受地层、岩相及构造热液双重因素控制,矿床成因属中低温沉积改造型矿床。成矿作用经历了沉积成岩和后期热液改造阶段。

Yundong lead-zinc deposit located in Xuefeng secondary rift basin of Nanhua rift basin,the ore hosting strata is Doushantuo formation of Sinian system,the host rock mainly is carbonate rock,little is clastic sedimentary rock,the orebody appears in bedded and near bedded,the mineral include sphalerite,pyrite and some galena,the ore texture mainly are grain and metasomatic relict texture,the ore structure mainly are stellate,streak,brecciform,grained Disseminated and vein,the wall rock alteration are carbonation,silication and baratization.The sulfur isotopeδ^(34) S is+13.5‰to+22.9‰,Cisotopeδ^(13) C_(PDB) is-4.7‰to-8.42‰,Oisotopeδ^(13) O_(PDB) is-13.31‰to-14.64‰,the ore forming temperature is 142℃to 255℃and belong to medium and low temperature ore forming fluid,the lead-zinc deposit are controlled by stratum,lithology and structural hydrothermal,the genesis of deposit is medium and low temperature reworked deposit.The mineralization experienced diagenesis stage and hydrothermal alteration stage in the late period.