陕西镇安二台子金铜矿床表生地球化学异常特征

为查明二台子金铜矿床的表生地球化学异常特征，采用土壤地球化学综合剖面的研究方法，对其进行了详细的分析研究。结果表明，区域上二台子金铜矿床的表生地球化学异常元素组合为Au-As-Sb-Hg-Cu，并表现出与原生异常在组合，含量等特征上的一致性。矿区内金、铜等成矿及指示元素在土壤中的不同层位产生了一定程度的富集。土壤和岩石样品的Au，As，Hg，Cu均密切相关。该矿床上覆的土壤及氧化矿石中的金主要以自然金相，水溶相和硫化物相形式存在，金的这种赋存相态特征可以作为寻找掩埋和隐伏金矿床的标志。

Characteristics of Supergene Geochemical Anomalies in Ertaizi Gold-Copper Orefield, Zhen'an, Shaanxi Province

By means of comprehensive geochemical soil cross section, the authors studied in detail characteristics of supergene geochemical anomalies in the Ertaizi gold_copper orefield. The results show that the supergene geochemical anomalies in the gold orefield have the element association of Au_As_Sb_Hg_Cu, consistent with characteristics of the primary anomalies. The ore_forming elements and indicator elements are concentrated to some extent in different soil layers in this area: Au, As and Ag are relatively abundant in the C layer of soil, Cu in the B and C layers, and Sb, Hg also in the C layer. Furthermore, Au, As, Hg and Cu in soil are closely related to their content in rocks, as shown by R_cluster analysis. The main modes of occurrence of gold in overlying soil of the ore deposit and the oxidized ore are native gold, soluble gold and sulphide phase of gold. The modes of occurrence of gold can be regarded as indicators for exploring buried and concealed gold deposits. It can be concluded that the factors controlling the development of supergene geochemical anomalies include geographical landscape, chemical and physical environments of soil, geological background, types of ore deposits, and geochemical characteristics of ore_forming and indicator elements.