摘要
通过对齐求Ⅰ号金矿床地质地球化学特征及控矿条件的研究,认为该矿床的成矿热液和矿质主要来源于附近海西晚期至印支期的花岗岩。岩浆中析出的岩浆热浪携带成矿物质,沿断裂通道上升,在大断裂附近的次级断裂和有利的围岩中成矿。在此过程中可有部分地下水加入成矿热液,而容矿围岩玄武岩是起到了促进矿质沉淀的作用。据此提出了该矿床为中温岩浆热液成因。
The Qiqiu No.1 gold deposit betongs to quartz vein type and the auriferous quartz veins fill in the secondary fractures in the hanging wall of Anqi Fault, The country rocks of the ore bodies mainly consist of basalt.Native gold,arsenop-yritc and pyrite are the main ore minerals of a content of 3-5% in average and often below l%.The native gold usually fills in the cracks of the quartz veins. Au/Ag ratio of ores ranges from 2.70 to 35.42.The homogenization temperature of the fluid inclusions in the Au-bearing vein quartz ranges from 320℃ to 160℃, largely from 270℃ to 200℃ . Comparison of the fluid components and stable isotope (S,H,O, C) composition of the fluid inclusions between the vein quartz from the ore bodies and from the granite pluton exhibits obvious consistency and/or similarity, which is convincing that the ore-bearing fluids were largely derived from the granites near the deposit.It is also recognized granites in this area bear a high gold content of 10.39 ppb.REE distribution patterns between the Au-bearing quar-tz veins and the granite are also consistent or similar.Therefore, the suthor believes that the Qiqiu No.l gold deposit is of a moderate temperature magmatic hydro-thermal origin.
关键词
金矿床
矿床
成因
岩浆热液
gold deposit, magmatic hydrothermal fluid, origin of deposit, Xin Jiang
