关键词: 控矿因素, 勘探大数据, 定量分析, 胶东金矿, 大尹格庄金矿床, 胶东半岛

Abstract: The Jiaodong gold deposit typically occurs in an extensional fault system and often exhibits obvious structural ore-control characteristics. However, the step metallogenic model of the Jiaodong gold deposit is inadequate to delineate the structural features that essentially control the formation of the deposit. The big data technology has provided a new approach to mine exploration data and explore minerogenetic regularities. In this paper, we studied the Dayingezhuang gold deposit in the Jiaodong peninsula. Based on the collected exploration data and using the spatial analysis method, we performed quantitative assessment of different features of ore-controlling factors to determine their association with gold mineralization. The results show a bimodal distribution between either gold grade or quantity and the fault distance factor. The bimodal distribution is consistent with the occurrence of two ore types in the gold deposit and directly indicates the relative spatial positions between the two ore types. Plot of gold grade vs. fault slope showed a near Gaussian distribution peaking at a slope range for large gold accumulation, suggesting that ore-forming fluids prefer to converge and remain at certain sloped sections. We observed that slope change and undulation of fault have significant effects on ore distribution and can clearly distinguish the locations of orebodies in terms of ore quality. We also observed sharp increase of gold accumulation in the intense alteration zone, where continuous hydrothermal process or multiple mineralization most likely had occurred. We conclude that the morphological features of the Zhaoping fault played key roles in the formation of the Dayingezhuang gold deposit. This conclusion may be applied to other Jiaodong gold deposits.

Key words: ore-controlling factor, exploration big data, quantitative analysis, Jiaodong gold deposit, Dayingezhuang gold deposit, Jiaodong Peninsula