多元统计分析在紫金山铜金矿床研究中的应用

The application of multivariate statistical analysis to study of the Zijinshancopper gold deposit

紫金山铜金矿床为典型的高硫化型浅成低温热液矿床。文章以矿山地质调查工作为基础,通过岩相学、矿相学、岩化学分析等方法对紫金山铜金矿中的赋矿围岩以及金属矿石进行了系统研究;应用多元统计分析法对蚀变围岩的岩石地球化学数据进行分析,借助SPSS系统研究了Cu-Au元素变量与控矿微量元素变量的聚类关系,建立了Cu-Au元素变量与其它变量的回归方程,验证与解释了紫金山Cu-Au高硫化型矿床的成矿作用是由多期次的岩浆热液活动引起的。另外,通过聚类分析研究发现紫金山的成矿过程主要有中温Cu-Au矿化、低温Pb-Zn矿化以及少量高温W-Sn矿化三种矿化类型,其中W-Sn矿化形成于燕山早期的赋矿围岩形成阶段,而Pb-Zn、Cu-Au矿化为主矿化成矿阶段、形成于燕山晚期,且与富潜火山热液活动有关。

The Zijinshan copper-gold deposit is the first typical high-sulfide epithermal deposit in mainland of China.Based on the geological survey,petrographic,mineralographic data,whole-rock chemical analysis and so on the host rock and the metal ore are systematiclly studied.Multivariate statistical analysis is applied to analysis of petro-geochemical data of altered wall rock.SPSS mathematical statistics software is used to study the clustering relations between Cu-Au variables and ore-controlling trace element variables systematically.Then the regression equation of Cu,Au and other variables is established and it can verify and explain the metallogenesis of Cu-Au high sulfide deposit is caused by multi-stage magmatic hydrothermal activity.In addition the clustering analysis shows that the metallogenic process of Zijinshan Cu-Au deposit includes the three main stages,i.e.the medium-temperature Cu-Au mineralization,low-temperature Pb-Zn mineralization and high-temperature W-Sn mineralization among which the W-Sn metallogenic stage is correspondent to formation stage of the host rock during the early Yanshan Period,the Pb-Zn and Cu-Au stages the main mineralization stage to the late Yanshanian Period stage and related to ore-material-rich latent volcanic hydrothermal fluid activity.