南非Kalahari锰矿田地质特征及找矿方法

Geological characteristics and prospecting methods of the Kalahari manganese field in South Africa

南非Kalahari锰矿田内发育众多大小规模的锰矿床,其形成与早期海底热液喷气及后期沉积变质作用密切相关。通过对比研究,区内矿体分布广泛、厚度不均,以层状、似层状、透镜状近平行产出,具有明显的层状分带特征。根据矿石类型可将其划分为Wessels型和Mamatwan型,矿石主要矿物成分以黑锰矿、铁锰矿、褐锰矿为主,样品数据表明Fe、Mn总体含量较为稳定,存在较为明显的负相关性,与古元古代的沉积环境和Fe、Mn物理性质关系密切。结合区域以往地质勘探资料,对区内锰矿地质特征、矿床成因及找矿方向进行了探讨,认为其成因类型为沉积变质型铁锰矿床,成矿后期的逆冲推覆构造和正断层破坏了矿体的连续性和完整性,白云岩溶蚀构造是铁锰物质的赋存空间,Hotazel组条带状含铁锰建造是区内找矿的重点部位。

There are many manganese deposits in Kalahari ore field in South Africa,the formation of which is closely related to early hydrothermal vent and late sedimentary metamorphism.Through comparative study,the ore bodies in the area are widely distribu⁃ted with uneven thickness,and they are produced in stratiform,stratiform and lenticular near parallel,with obvious stratiform zonation characteristics.According to the ore types,it can be divided into Wessels type and Mamatwan type.The main mineral composition of the ore is black manganese ore,ferromanganese ore and brown-manganese ore.The sample data shows that the overall content of Fe and Mn is relatively stable and there is a relatively obvious negative correlation,which is closely related to the paleoproterozoic sedimentary environment and the physical properties of Fe and Mn.In combination with regional geological exploration data,the manganese ore geo⁃logical characteristics,ore genesis and prospecting direction are discussed in this paper,and its genetic type is sedimentary metamor⁃phic type iron manganese deposit,ore-forming later thrust nappe and normal fault destroyed the continuity and integrity of the ore bodies,dolomite karst structure is the occurrence of iron manganese material space,article Hotazel group banded iron manganese building is the key parts of prospecting in the area.