塞拉利昂中部马卡利地区金矿特征及成矿远景

Characteristics and potential of gold deposit in the Makali region of central Sierra Leone

塞拉利昂中部马卡利地区出露有大片的太古界花岗-绿岩带地质体,其金矿资源丰富。通过矿产勘查和成矿规律研究表明,金的来源与太古界花岗-绿岩带地体密切相关。岩金矿床类型为含铁建造金矿床,主要赋存于绿岩带的绿片岩中及含铁建造的片岩中,受褶皱和断裂构造控制;砂金矿的类型为河流冲积型砂金矿,主要分布在花岗-绿岩带内及其周边河流中的全新统冲积层中下部砂砾石层中。重砂异常和地球化学异常区内具备良好的岩金、砂金成矿地质背景和找矿前景,实施砂金-岩金综合找矿方法,找矿潜力巨大。

Large area exposure of Archean granite-green stone terrain occur in Makali region of central Sierra Leone and is abindant with gold mineral resources.The mineral exploration and metallogenic regularity study show that the source of the gold in the region is closely related to Archean granite-green stone terrain.The primary gold deposit is BIFtype gold deposits occuring mainly in the green schist in greenstone belt and schist in BIF.They are controlled by fold and fracture.Placer gold deposit is mainly fluvial type distributed grnerally in sandy gravel layers at middle-lower holocene strata.Heavy mineral and geochemical anomly areas are of good background for formation of placer gold and primary gold deposits thus potential for integrated prospecting of placer gold and primary gold deposits.