湖南桂阳县白沙子岭锡矿床地质地球化学特征及其成因  

Geological and geochemical characteristics and genesis of the Baishaziling tin deposit, Guiyang County, Hunan

作　　者：曾志方[1] 曾佐勋[1] 曾永红[2] 邹建林[2] 胡才志[1] 

机构地区：[1]中国地质大学研究生院,湖北武汉430074 [2]湖南省地质矿产勘查开发局四一八队,湖南娄底417000

出　　处：《中国地质》2008年第4期725-737,共13页Geology in China

基　　金：中国地质调查局地质大调查项目(199910200220);国土资源部矿产资源补偿费项目(200401422)资助

摘　　要：白沙子岭锡矿床赋存于大义山复式花岗岩体内,发育蚀变花岗岩型和云英岩脉型两个主要矿床类型,两类矿床在空间上相伴产出。通过矿床成矿地质背景和地质特征的研究,运用同位素和包裹体测试成果,探讨了矿床成因及成矿作用过程。铅同位素表明,锡成矿物质为幔、壳源混合来源。氢、氧同位素特征指示成矿流体主要为沸腾岩浆水。云英岩脉型和蚀变花岗岩型锡矿脉(体)在空间上的耦合性以及它们的流体包裹体和硫、铅同位素特征表明,构造作用和岩浆演化的联合作用是成矿的主要控制因素。成矿温度为130～425℃,盐度为1.40%～11.22%,成矿压力为67×105～537×105Pa。矿床属中高温岩浆热液矿床。The Baishaziling tin deposit is hosted in the Dayishan composite granite body. Two types of tin deposit, altered granite type and greisen vein type, are distinguished, and they occur in association with each other in space. The paper discusses the genesis and ore-forming processes of the deposit according to the geological setting and geological characteristics of the deposit and the results of isotope and inclusion analyses. Pb isotope study shows that ore-forming materials of tin were derived from the mixed source of mantle and crust. Hydrogen and oxygen isotope features indicate that ore-forming fluids were mainly boiling magmatic water. Coupling of altered granite-type and greisen vein-type tin ore veins and consistency of their fluid inclusion and sulfur and lead isotope features show that the combined effect of tectonism and magmatic evolution was the main controlling factor for mineralization. With temperatures of 180-425℃, a salinity of 1.40-11.22% and pressures of （67-537）× 10^5Pa, the Baishaziling tin deposit is a mesothermal-hypothermal deposit.

关 键 词：蚀变花岗岩型 云英岩脉型 地质地球化学 成因 白沙子岭 

分 类 号：P618.44[天文地球—矿床学]