The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage miner...The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage mineralization due to shearing, middle-stagemineralization due to hydrothermal alteration, and late-stage mineralization due toweathering, leaching and concentration at shallow depths. Shearing played a dominant role inthe formation of gold orebodies.展开更多
Based on detailed geologic study, the important role of structuring in the formation of gold deposits in the area is discussed with special reference to structural evolution. Syngenetic faulting contemporaneous with t...Based on detailed geologic study, the important role of structuring in the formation of gold deposits in the area is discussed with special reference to structural evolution. Syngenetic faulting contemporaneous with tectonic-volcanic events is thought to be responsible for providing the ore-forming material at depth. The lithofacies formed by highly alternating deposition of terrestrial and carbonate detritus is chemically characterized by the assemblage of Au-Sb-As,constituting a favorable source bed for the activation and enrichment of gold. This gold source bed has undergone four major stages of structural deformation, accompanied by multi-staged alteration and mineralization.展开更多
陕西青木川—苍社地区位于勉略宁三角区的南带,区内金的矿化类型有蚀变岩型、石英脉型及磁铁石英岩型等。金矿体均赋存于碧口群地层中,其空间定位和富集严格受N E和N E E向韧性剪切带的控制。对该成矿带旧房梁、小燕子沟、金厂沟及火峰...陕西青木川—苍社地区位于勉略宁三角区的南带,区内金的矿化类型有蚀变岩型、石英脉型及磁铁石英岩型等。金矿体均赋存于碧口群地层中,其空间定位和富集严格受N E和N E E向韧性剪切带的控制。对该成矿带旧房梁、小燕子沟、金厂沟及火峰垭金矿的流体包裹体、硫同位素及稀土元素进行分析。研究结果表明：含金石英脉中仅见富液相水溶液包裹体,其均一温度集中在1 8 0～3 4 0℃之间,盐度（质量分数）一般小于5%,成矿流体属中温低盐度的N a C l-H2O体系,成矿压力范围峰值为4 5～8 5 M P a,成矿深度较浅,达1.6 7～3.1 5 k m,可能代表韧性剪切带中浅部脆性变形域中的矿化。不同类型矿石的稀土配分模式与其围岩极为相似,暗示成矿流体和成矿物质来源可能来自地层。金矿石中黄铁矿的硫同位素组成一般为负值,均接近陨石硫,暗示成矿物质可能来源为碧口群地层。该区韧性剪切带型金矿中不同类型的金矿化在同一矿床中叠加出现可能与矿化形成过程中韧性剪切带不断被抬升剥蚀有关。展开更多
基金This paper represents partial results of a major project(No,49290100)supported by the National Natural Science Foundation of China.
文摘The Baguamiao gold deposit in Fengxian County, Shaanxi Province, is a recentlyexplored super-large gold ore deposit. A comprehensive and deep-going study has revealedthat it is a polygenetic deposit: early-stage mineralization due to shearing, middle-stagemineralization due to hydrothermal alteration, and late-stage mineralization due toweathering, leaching and concentration at shallow depths. Shearing played a dominant role inthe formation of gold orebodies.
文摘Based on detailed geologic study, the important role of structuring in the formation of gold deposits in the area is discussed with special reference to structural evolution. Syngenetic faulting contemporaneous with tectonic-volcanic events is thought to be responsible for providing the ore-forming material at depth. The lithofacies formed by highly alternating deposition of terrestrial and carbonate detritus is chemically characterized by the assemblage of Au-Sb-As,constituting a favorable source bed for the activation and enrichment of gold. This gold source bed has undergone four major stages of structural deformation, accompanied by multi-staged alteration and mineralization.
文摘陕西青木川—苍社地区位于勉略宁三角区的南带,区内金的矿化类型有蚀变岩型、石英脉型及磁铁石英岩型等。金矿体均赋存于碧口群地层中,其空间定位和富集严格受N E和N E E向韧性剪切带的控制。对该成矿带旧房梁、小燕子沟、金厂沟及火峰垭金矿的流体包裹体、硫同位素及稀土元素进行分析。研究结果表明：含金石英脉中仅见富液相水溶液包裹体,其均一温度集中在1 8 0～3 4 0℃之间,盐度（质量分数）一般小于5%,成矿流体属中温低盐度的N a C l-H2O体系,成矿压力范围峰值为4 5～8 5 M P a,成矿深度较浅,达1.6 7～3.1 5 k m,可能代表韧性剪切带中浅部脆性变形域中的矿化。不同类型矿石的稀土配分模式与其围岩极为相似,暗示成矿流体和成矿物质来源可能来自地层。金矿石中黄铁矿的硫同位素组成一般为负值,均接近陨石硫,暗示成矿物质可能来源为碧口群地层。该区韧性剪切带型金矿中不同类型的金矿化在同一矿床中叠加出现可能与矿化形成过程中韧性剪切带不断被抬升剥蚀有关。
