湘中包金山金矿床地球化学垂向分带特征及指示意义

Geochemical Vertical Zonation Characteristicsand Indication of geochemistryin Baojinshan Gold Deposit in the central area of Hunan

通过运用格里戈良指数分带法分析包金山金矿床构造地球化学样品测试数据,总结了湘中包金山金矿床地球化学垂向分带特征。包金山金矿床原生晕垂向分带序列由浅到深依次为Ag-Sn-As-Mo-Pb-Zn-Hg-Tl-Mn-W-Au-Cu-Sb,整体呈现出(前—尾—近)—(前—尾—近)—(前—)的叠加分布规律。结果表明,金矿床较早期成矿尾晕以叠加晕的形式叠加于较晚期前缘晕和近矿晕之上,反映了该矿床至少存在3期成矿作用叠加。矿床主成矿期近矿晕(Au、Cu)出现,但未结束,晚期仅出现前缘晕(Sb),近矿晕和尾矿晕还未出现,因此,矿床边深部找矿工作应重点围绕该两期成矿作用形成的矿化富集带部署。

This paper analyzed and summarized the geochemical vertical zonation characteristics of primary halos in the Baojinshan gold deposit,central area of Hunan Province,using the C·B·Gregorian’s zoning index method. The vertical zonation elements sequence from shallow to depth is Ag-Sn-As-Mo-Pb-Zn-Hg-Tl-Mn-W-Au-Cu-Sb. It presented( front-rear-sub ore)-( frontrear-sub ore)-( front-) superposition distribution characteristics. The results showed that the rear halos of early stagemineralization superimposed on the front halos and sub-ore halos of late stage mineralization.Sub-ore halos( Au、Cu) in the main mineralization period had appeared,but it is not the end. And there are only front halos( Sb) in the late mineralization period andthe sub-ore halos and rear halos still did not appear. It is proved that there is a superposition of three mineralization periods at least. Meanwhile we should consider these two mineralization enrichment zones as targets of future depth and margin prospecting.