Research Opportunities on the Metallogenesis of Sediment-hosted Base Metals within the Coastal Branches of the Damara Orogenic Belt in Namibia

摘要

The present literature review on sediment-hosted base metals in Namibia, conducted as one of BGR's university research projects, has revealed that the subject holds a number of highly challenging research opportunities. This country in southern Africa has a particularly long and successful mining history of this wide and complex group of ore deposits, thus providing good case studies and excellent data base. Two base-metal districts (Zn-Pb-Cu-A) in the coastal region of Namibia, the Rosh Pinah/Skorpion district in the southwest and the Tsongoari/Rendezvous district in the northwest, are host to significant mines or prospects of disputed metallogenetic origin. One of the deposits, the Skorpion mine, contains Zn silicates, oxides, and carbonates and is a prominent example of the recently rediscovered group of "nonsulphide" Zn deposits. These ore deposits have become the focus of international scientific and industrial attention, since they are economically, environmentally, and politically more attractive than the conventional Zn sulphide deposits, which face problems due to their waste of sulphur and lead, which are increasingly undesirable by-products.The sediment-hosted base-metal deposits of the coastal region of Namibia are hosted by Pan-African mobile belts and have not been fully investigated by the latest isotope, geochemical, mineralogical, and geophysical techniques. The metallogenetic evolution of both Namibian metal districts still waits to be fully explained and especially the identification of geochemical and mineralogical vectors (proxies) to ore requires a modern approach to metallogenetic research. The identification of those vectors, which are the least modified by the metamorphism, poses one of the currently most challenging scientific problems.