黔西南泥堡金矿床容矿火山岩系中“粉砂岩”夹层的岩石类型归属研究  

Study on Petrologic Classification of“Siltstone Sandwich”in Ore-bearing Volcanic Rocks of Nibao Gold Deposit,Southwest Guizhou

作　　者：祁连素 QI Liansu(Ghozhou Institute of Geopysical and Geochemical Prospecting,Guiyang 550018,Guizhou,China)

机构地区：[1]贵州省地矿局地球物理地球化学勘查院,贵州贵阳550018

出　　处：《贵州地质》2021年第1期22-28,64,共8页Guizhou Geology

基　　金：贵州省地矿局地质科技项目《贵州普安泥堡地区峨眉火山活动与金成矿关系研究》资助。合同编号:黔地矿科合〔2019〕10号。

摘　　要：原先认为泥堡金矿床容矿火山岩系中间的“粉砂岩夹层”,研究发现其具有与火山碎屑岩的成分与结构构造特征,包括熔蚀石英晶屑和长石板状晶假象,局部还出现大量生物化石碎片,应归属为蚀变凝灰岩。火山岩系的原“粉砂岩夹层”并不存在,只是短暂的火山喷发间隙,整个容矿火山岩系形成从偏基性火山碎屑岩到中基性火山角砾岩的晚二叠世火山喷发旋回。火山岩旋回的早期到晚期,金矿成矿作用强度逐渐增强,印证金成矿作用与火山岩的密切成因联系。In the study,the formerly deduced“siltstone sandwich”in ore-bearing volcanic rocks of Nibao gold deposit should be a kind of altered tuff,because it possesses the volcaniclastic composition,texture and structure,including melting quartz crystal fragment,feldspar plate crystal pseudomorph,as well as lot of fossils fragments.The former“siltstone sandwich”is not exist,only a short gap of volcanic eruption.The whole volcanic rock series become a late Permian volcanic eruption cycle frompartially basic volcaniclastic rock to intermediate basic volcanic breccia.From early stage to late stage of volcanic cycle,the strength of gold mineralization enhanced gradually,it proves the closed relationship between gold mineralization and volcanic rock.

关 键 词：蚀变凝灰岩 火山喷发间隙 晚二叠世火山作用 泥堡金矿床 贵州 

分 类 号：P618.51[天文地球—矿床学] P588.1[天文地球—地质学]