平江万古金矿床地球化学研究

Geochemistry of Wangu Gold Deposit

平江万古金矿床，成矿物质来源于容矿地层中元古界冷家溪群坪原组，矿床继承了容矿地层富Ａｓ、Ｓｂ、Ｗ等微量元素的特点，成矿流体为与区域浅变质作用有关的ＨＣＯ＿３－－Ｃｌ－－Ｎａ￣＋－Ｃａ￣（２＋）型建造水热液，成矿过程中Ａｕ主要以ＡｕＡｓＳ＿２、ＡｕＡｓＳ＿３￣（２－）络合物形式迁移，矿床形成于中一低温，弱碱性、还原环境。

Ore-forming material of Wangu gold deposit in Pingjiang comes from ore-storing stratum,Ping-yuan formation of Mid-proterozoic Lengiiaxi group.The deposit inherits the characteristics of ore-stor- ing stratum rich in As,Sb and W. Ore-forming solution is HCO_3--Cl--Na￣+-Ca￣(2+) type formation thermal water related to regional metamorphism. In the process of mineralization, Au migrates mainly in complex forms of AuAsS_2 and AuAsS_3￣(2-) .The deposit forms under the circumstance of middle-low temperature,weak alkali and reduction.