Geology of Zimbabwe

The geology of Zimbabwe in southern Africa is centred on the Zimbabwe Craton, a core of Archean basement composed in the main of granitoids, schist and gneisses. It also incorporates greenstone belts comprising mafic, ultramafic and felsic volcanics which are associated with epiclastic sediments and iron formations. The craton is overlain in the north, northwest and east by Proterozoic and Phanerozoic sedimentary basins whilst to the northwest are the rocks of the Magondi Supergroup.^[1] Northwards is the Zambezi Belt and to the east the Mozambique Belt. South of the Zimbabwe Craton is the Kaapval Craton separated from it by the Limpopo Mobile Belt, a zone of deformation and metamorphism reflecting geological events from Archean to Mesoproterozoic times. The Zimbabwe Craton is intruded by an elongate ultramafic/mafic igneous complex known as the Great Dyke which runs for more than 500 km along a SSW/NNE oriented graben. It consists of peridotites, pyroxenites, norites and bands of chromitite.^[2]

Economic geology

Zimbabwe's mineral resources include, amongst others, coal, chromium ore, nickel, copper, iron ore, vanadium, tin, platinum group metals (such as palladium) and diamonds. Globally it is a significant producer of lithium, chrysotile asbestos and vermiculite. Gold, platinum group metals and chromium are Zimbabwe's key mineral resources. The Great Dyke provides most of Zimbabwe's chromium reserves. Zimbabwe experienced a decline in the mining of many minerals in the period to 2008 including the closure of several gold mines. However, diamond production increased making the country Africa's seventh largest producer by 2008.^[3]

The country has considerable coal reserves which are used in power generation. Its coal-bed methane field, the largest in southern Africa has not yet been exploited to the full.^[4]

References