博茨瓦纳东北部铜矿、铜镍矿成矿地质特征及典型矿床实例

Geological Characteristics and Examples of Typical Deposits of Copper,Copper-nickel Deposits in Northeast Botswana

博茨瓦纳东北部地区由北向南分布有津巴布韦克拉通、林波波活动带和卡普瓦尔克拉通等三个重要的成矿构造单元。从成矿地质条件和已发现的矿床看,博茨瓦纳东北部太古代地层是寻找铜矿、铜镍矿的有利地区。在博茨瓦纳东北部分布有塞莱比—皮奎、马齐塔玛、赛尔科克三大铜镍矿化密集区,已发现铜镍矿床(点)多达40余个。该区具有广阔的铜矿、铜镍矿勘探前景。对博茨瓦纳的铜矿、铜镍矿的区域地质背景和矿床地质特征进行分析和总结,认为该区的铜矿、铜镍矿主要有热液型铜矿和与基性—超基性岩有关的岩浆型铜镍矿两种类型,前者往往与构造破碎带关系密切,后者与角闪岩和蛇纹岩相伴生。对本区典型矿床成矿地质特征研究与总结,以期为本区勘探工作起指导性作用。

The three most important metallogenetic tectonic units in southern Africa-the Zimbabwe Craton,the Kaapvaal Craton and Limpopo Mobile Belt extend through Botswana.From the view of metallogenic geological conditions and discovered deposits,the archean strata in northeastern Botswana are favorable for the exploration of copper and copper-nickel deposits.In the northeast of Botswana,there are three concentrated areas of copper and nickel mineralization,such as Selebi-Phikwe,Matsitama and Selkirk.More than 40 copper and nickel deposits (occurrences) have been discovered.The paper analyzed and summarized regional geological background and geological characteristics of copper,copper-nickel deposits in northeast Botswana,there are two mainly types of copper and copper-nickel deposit in this area:hydrothermal copper deposit and magmatic copper-nickel deposit related to basic and ultrabasic rocks.By studying and summarizing the metallogenic geological characteristics of typical deposits,this paper hopes to play a guiding role in the exploration of this area.