【作者】 王可新；

【导师】 王建平；

【作者基本信息】 中国地质大学(北京) ， 矿物学、岩石学、矿床学， 2012， 硕士

【摘要】 陕西双王金矿床位于西秦岭凤太矿集区东部，为一大型含金钠长角砾岩型金矿床。矿床赋矿地层为上泥盆统星红铺组，为一套由钙质粉砂岩、粉砂质绢云板岩和灰岩组成的类复理石沉积建造。金矿体明显受角砾岩体控制，呈断续带状分布，矿石硫化物主要为黄铁矿，主要围岩蚀变类型为钠长石化。本文在矿床地质特征研究基础上，系统分析了该矿床岩（矿）石的主量元素、微量元素、稀土元素和稳定同位素的组成特征，取得以下主要成果和认识：双王金矿床含金角砾岩体为气液隐爆作用形成。其形成与区内晚印支期岩浆活动有密切关系，属于气液隐爆角砾岩。双王成矿带由若干个构造活动较强烈的热液活动中心—隐爆中心控制成矿。双王金矿带由西向东分布四个隐爆中心，隐爆中心地质特征表现为热液活动较强烈，野外宏观地质现象显示隐爆中心由西向东逐渐加深。将矿床成矿过程分为隐爆前交代成矿期和隐爆后充填成矿期两大成矿期，其中隐爆前交代成矿期以热液交代作用为主，隐爆后充填成矿期以充填成矿作用为主，金成矿主要发生在隐爆后充填成矿期的铁白云石-黄铁矿阶段。岩（矿）石的主量元素、微量元素和稀土元素特征显示， Au可能在星红铺组地层中有预富集，构成金的初始矿源层；西坝岩体和围岩在矿石形成过程中可能均提供了部分成矿物质。稳定同位素研究表明：成矿流体由早期岩浆热液和建造水热液的混合热液向晚期岩浆热液、大气降水热液演化；碳可能主要来源于深部，部分来源于地层；硫源即有深部岩浆硫源，也有地层硫源的加入；铅主要来源于上地壳，并混有地幔物质，具有多来源混合铅的结构特征。探讨了双王金矿床的成因类型并建立了成矿模式，认为双王金矿床属于气液隐爆角砾岩型金矿床。矿床主要形成于晚印支期扬子板块和华北板块全面碰撞之后的后造山环境，矿床的形成经历了早期的热液对围岩的交代作用和气液隐爆作用之后的充填成矿作用。更多还原

【Abstract】 The Shuangwang gold deposit, located in the east of the Fengtai ore concentrationarea of the West Qinling, is a large gold deposit of auriferous albite breccias type. The oredeposit occurs in the weakly metamorphosed upper Devonian Xinghongpu Group,dominated by calcareous siltstone, sericite silty slate and carbonate that comprise flyschoidformation. Gold mineralization is strictly controlled by auriferous breccia bodies. Pyrite isthe most important ore sulfide and the main wall-rock alteration is albitization. Based onthe research of the geological features of the deposit, this paper has systematicallyanalyzed the composition characters of the major elements, the trace elements, the rareearth elements and the stable isotope. The main achievements and conclusions that we gotare as follow:The breccia bodies of Shuangwang gold deposit were formed by the effect ofgas-liquid’s hidden exploding. The formation of the breccia bodies has close connectionwith the magatic activities of the Late Triassic, so we classified the breccia to the hiddenexploding breccia. The mineralization of Shuangwang metallogenic belt was controlled byseveral centers of hydrothermal activities which we called hidden exploding centers. Theare four hidden exploding centers in Shuangwang metallogenic belt from the west to theeast, which explored the geological features of strong hydrothermal activities. From thewest to the east, the hidden exploding centers were deeper as we saw from the filedgeological features.The gold mineralization could be divided into two stages, which we called themetasomatism stage before blasting action and the filling stage after blasting action. Theformer stage was mainly by the metasomatism and the latter stage by the filling, themineralization of gold mainly happened in the stage of ankerite-pyrite. The main elements,trace elements and REE elements analysis indicated that Au may had preconcentration inthe formation of Xinghongpu Group and this composed the source bed of gold deposit.Systematic stable isotope analysis results show that the ore-forming fluids of early andmain stages came from mixture fluids and the late mainly came form magmatichydrothermal fluids with little meteoric water. Carbon was mainly derived from the great depth and partly from dissolution of carbonate strata. Sulfur is the mixture sulfur of crustand magma. Lead mainly came from upper crust and mixed little mantle lead.Based on this study, we investigated the genetic type and established the metallogenicmodel of Shuangwang gold deposit. We think that The genetic type of the Shuangwanggold deposit is hidden exploding breccia type gold deposit. The mineralization of theShuangwang gold deposit relates to the post-orogenic environment after the collisionbetween of the North China Plate and the Yangtze Plate in Late Triassic. The early stagemineralization was mainly caused by hydrothermal metasomatism and the main goldmineralization occurred in the hydrothermal filling stage after blasting action.更多还原