新疆西南天山布隆金矿床类型与成矿模式

摘要

布隆金矿是新疆西南天山的一座小型金矿床，金矿体主要赋存在层间滑脱断裂中，围岩为泥盆系紫红色、灰黑色砂岩和粉砂岩，成矿时代与中亚南天山金矿床的成矿时代一致，为晚二叠世。通过与中亚浅变质碎屑岩型金矿和新疆西南天山萨瓦亚尔顿金矿地质特征的对比研究可知，布隆金矿成矿特征基本符合浅变质碎屑岩型金矿的特点，其矿床类型应为浅变质碎屑岩型。矿区泥盆系克孜尔塔格组碎屑岩Au（Ba）元素浓集系数高、变化系数大，该地层为金矿的主要矿源岩；布隆断裂既是矿区已知矿脉的导矿断裂，也是容矿断裂。在分析控矿因素的基础上，建立了矿床成矿模式，指出泥盆系与石炭系不整合面和克孜尔塔格组千枚岩化灰黑色砂岩是下一步找矿的重要目标。%Bulong gold deposit formed in late-Permian is a small scale gold deposit in Southwest Tianshan, Xinjiang.Orebodies are mainly located in detachment fault belts between layers of Devonian purple,grey-black sandstones and siltstones.Through a comparative research on low metamorphic clastic rock gold deposit in Central Asia,Sawayardun gold deposit in Southwest Tianshan and Bulong gold deposit,a crucial conclusion is made that Bulong gold deposit is a low metamorphic clastic rock gold deposit type.Devonian Kezrtage formation clastic rock,which has a distinct geochemical feature of high Au coefficients of concentration and variation,is an origin of ore elements.Bulong fault is considered as a transport and precipitation fault.Metallogenic model is established according to analyzing ore-controlling factors and unconformable faults between Devonian and Carboniferous strata and gray-black phyllitic sandstones are advised to prospect ores.