陕西青山金矿床地球化学特征及成因

对青山金矿床的野外地质调查以及矿石与围岩的地球化学分析表明，成矿元素以Au-Ag-As-Sb-Ba组合为特征；赋矿地层中Au含量远大于背景值；围岩及矿石都具有较高的U/ Th值，其稀土元素配分形式基本一致，且存在Ce 负异常和Eu的正异常；成矿流体氢氧同位素值具明显的“氧漂移”现象；成矿流体温度介于160～220 ℃；流体包裹体中Ca^2＋，CO₂ 和HCO_-³含量较高，显示成矿流体为重碳酸盐-氯化钠型地下热卤水。因此矿床为泥盆系矿源层中的Au，在浅成低温条件下，经过雨水来源的地下热卤水长期循环改造、富集、沉淀在构造网络中，形成热泉型金矿床。

Geochemical Characteristics and Metallogenesis of Qingshan Gold Deposit in Shaanxi Province

The field geological investigation of Qingshang gold deposit and the geochemical analysis of its ore and country rock indicate that the ore-forming association is Au-Ag-As-Sb-Ba; the Au content in the ore occurrence stratum is far greater than the background value; both the country rock and ore have a high U/Th value, a basically identical rare earth element distribution, and Ce negative anomaly and Eu positive anomaly; the hydrogen and oxygen isotope values of the ore-forming fluid have an evident “oxygen drift”; the metallogenic temperature ranges between 160 ℃ and 220 ℃; and the fluid inclusions have high contents of Ca2＋, CO₂ and HCO_-³, indicating that the ore-forming fluid is underground thermal brine of bicarbonate-sodium chloride type. It is suggested that Qingshan gold deposit of hot spring type is formed by the chronically repeated recycling, transformation, enrichment and settlement of the Au from the source bed in the Devonian system by the underground hot brine originating from rainfall.