微细浸染型金矿床矿体与围岩对比研究

The comparison between orebodies and wall rocks of the fine disseminated gold deposits

桂西北凤山金牙中三叠统微细浸染型金矿床产于浊积岩中。矿床中的有机质含有丰富的流体运移和载Au信息 ,这种信息可以通过矿体与围岩的对比分析进行揭示。有机与无机地球化学分析所揭示的矿体与围岩有机质丰度、氢指数、C有效 、降解率、生物标志物和Au含量等存在着差异 ,这些差异由含烃成矿流体活动引起。运移烃类的叠加不仅使矿体C有机 含量明显增加 ,而且对Au在矿体部位的富集也有直接的贡献。有机质在桂西北凤山金牙中三叠统浊积岩型金矿床的成矿过程中也起了重要作用。

The Jinya fine disseminated gold deposit in the northwestern Guangxi of Middle Triassic occurred in turbidites.The organic matter in gold deposit shows plentiful information on fluid's migration and Au-carrying.The information can be revealed by the analyses of comparison between orebodies and wall rocks.The abundance of organic matter,hydrogen index,effective carbon,degradation degree, biomarkers and gold content are different between orebodies and wall rocks, it is suggested to be caused by activities of hydrocarbon-bearing metallogenic fluid during diagenises.The migrated organic matter in the fluid not only caused the increase of organic carbon in orebodies but also made a contribution to the enrichment of gold in orebodies. It's suggested that the organic matter takes an important role in the formation of the Jinya gold deposits in Fengshan of the northwestern Guangxi.