津巴布韦马尼卡兰金刚石古砂矿地质特征及找矿意义

通过对南部非洲津巴布韦东部马尼卡兰金刚石古砂矿的矿体特征、矿石特征、赋矿规律、金刚石特征的研究,认为该区金刚石砂矿主要为固结砂砾岩型古砂矿与河流冲洪积砂砾层型金刚石砂矿。研究显明,2种金刚石矿床类型之间具有物质间的承生关系。在元古代,原生矿中的金刚石被风化剥离出来,经流水的搬运,在滨海地区沉积下来,并被后来沉积的灰岩覆盖,固结形成金刚石古砂矿床。该古砂矿的发现及研究,对于指导非洲乃至我国类似矿床的找矿工作具有重要的借鉴意义。

Geologic Characteristics and Exploration Significance of Diamond Paleoplacer in Manicaland of Zimbabwe

This thesis researches the ore body feature, ore feature, ore bearing rules, and diamond feature etc of diamond paleoplacer of eastern area Manicaland of Zimbabwe of southern Africa. The diamond placers of this area are mainly solidification glutenite paleoplacer and river alluvialdiluvial glutenite diamond placer, in total two types. The research shows that there is physical bearing relation between such two diamond ore deposits. The diamond in primary deposit was stripped by weathering and moved by river to deposit at coastal region, be covered by deposit limestone and solidify as diamond paleoplacer ore deposit during the Proterozoic era. The exploration and research of paleoplacer has great significance to guide similar exploration works of Africa and China.