安徽省兆吉口铅锌矿床成矿地球化学机制研究

自20世纪30年代起, 勘查地球化学就在矿产资源勘查领域发挥着重要作用。目前, 矿业界对勘查地球化学回归到基础勘查理论研究有着明确的需要。多维异常体系应用基础理论的提出是我国学者在该领域的积极响应。多维异常体系定义为“在特定的成矿地质时期, 成矿系统中存在的空间有序共存、成因机理各异、成矿指示递进的多属性异常体系”。其中, 多属性异常的形成机制及其在成矿空间中的结构关系, 是探讨矿床成矿地球化学机制和指导矿产勘查的基础, 同时也是勘查地球化学研究的前沿方向。本论文以位于安徽省东至县的兆吉口浅成低温热液型铅锌矿床为研究对象, 通过元素质量迁移定量计算, 研究典型剖面上元素活动规律, 构建矿致异常结构模式, 揭示矿床成矿地球化学机制; 利用图示方法展现不同水平断面上元素异常分布形态, 为深部成矿预测指明方向; 利用分形模型和基于成分数据理论的主成分分析、因子分析等方法, 研究地表岩屑中元素分布特征及影响因素, 指导研究区外围矿床地球化学勘查。

The Ore-forming Geochemical Mechanism of the Zhaojikou Pb-Zn Ore Deposit, Anhui Province

Geochemical exploration has been playing a very important role in the field of mineral resources pros-pecting and evaluation. At present, the mining indus-try has a clear demand that the study of geochemical exploration should return to the focus of the basic theory. The multi-dimensional anomaly system (MAS) is one of Chinese responding in this regarding. MAS means that anomalies of many attributes which formed in different ways during a specific ore-forming period co-exist sequentially in space and indicate the ore bodies/deposits progressively. The spacial structure and formation processes of multi-attribute anomaly in MAS are the foundation to study ore-forming geochemical mechanism and pros-pect new ore bodies/deposits. Meanwhile, it is also the cutting edge of exploration geochemistry. In this dissertation, we selected the Zhaojikou epithermal Pb-Zn ore deposit, Anhui Province, as the object of study. First of all, the method of mass-transfer balance was used to study the elemental mobility in the ore- forming process, to construct an ore-forming anomaly model, and to reveal the ore-forming geochemical mechanism. Then, the distributions of elements of interest in different levels were visualized to show the ore prospecting direction in the deep. Fi-nally, fractal model and PCA and factor analysis based on the compositional theory were used to study the distributions, anomalies, and controlling factors of elements of interest in the surface to help the geo-chemical exploration projects in the periphery of the Zhaojikou District.