多龙矿集区控矿构造信息提取、识别与融合

西藏多龙矿集区近年来发现了大量的铜、金矿床,具有可观的资源潜力而倍受关注。通过对区内地质调查及矿产勘查数据的系统梳理与二次开发,利用基于分形理论的空间分析方法对该区成矿背景、构造格架等方面进行了深入细致的研究与探索。通过主成分分析方法,将水系沉积物地球化学数据中与斑岩铜金成矿相关元素和构造活动指示元素进行融合,并利用S-A(能谱-面积)模型对元素组合异常进行信息挖掘工作。结果表明,与区内构造格架相关的地球化学异常空间分布模式在指示矿化的同时,还对其与区域断裂构造之间的成生关系具有相当程度的指示意义。此外,区内开展的空间定量研究同时表明,S-A(能谱-面积)模型对描述由特定地质作用所造成的异常空间分布模式的自相似性有效,特别是针对地球化学背景模式的空间定量化描述,能更加深刻地刻画区内的构造格架并反映成矿背景。其结果推断了控制区内斑岩成矿系统的网格状断裂体系。此外,数据分析建模过程为在该区开展进一步的多元信息提取与融合提供了思路和借鉴经验,有利于找矿新靶区的发现与圈定。

Geo-information Extraction and Integration of Ore-controlling Structure in the Duolong Ore Concentration Area of Tibet

The study area, Duolong ore concentration area of Tibet, is not a well-developed area; nevertheless, it has received attention in recent years due to its considerable production of Cu-Au resources. In this study, the authors utilized fractal/multifractal analytical techniques to gain insights into the geological environment and metallogenesis of ore deposits so as to guide mineral exploration in this area. Porphyry Cu-Au mineralization related elements and fault-activity indicator elements from geochemical data of stream sediments were integrated by principal component analysis, and the results were further analyzed by spectrum-area model. Identified geochemical anomalies spatially coincident with structural framework not only imply the presence of mineralizdation but also suggest genetic relationship between mineralization and regional fault structures. This study inferred network structural control on porphyry mineralization, and identified background geochemical patterns of multi-element association by fractal/multifractal analyses, which further provides indirect and/or proxy geo-information of the network structure for supporting mineral exploration in the Duolong ore concentration area.