The Okiep Copper District situated in the north-western Cape Province, covers some 3 000 km and is the oldest mining area in the Republic of South Africa. The O'okiep Copper Company Limited commenced production in 1940 with a proven ore reserve of 9 million tons at 2,45 % cu. Production since 1940 and present ore reserves total some 93 million tonnes at 1,08 % Cu. The rocks comprising the Okiep Copper District are of Proterozoic age and have been subdivided into a meta-volcanosedimentary succession, intruded by various sub-horizontally emplaced granitoid intrusions. The various intrusions occurred at different stages relative to the main structural and metamorphic events. The copper deposits are confined to basic rocks which are the youngest major group of intrusives in the District. They occur as swarms of generally easterly-trending, steep northdipping, irregular dyke-like bodies consisting of diorite, anorthosite and norite. The dominant silicate constituents are andesite ranging to labradorite, hypersthene, biotite and phlogopite. Copper sulphides are preferentially associated with the more basic varieties. The copper sulphides are mainly chalcopyrite, bornite and subsidiary chalcocite. The copper content of the basic rocks is erratic ranging over small distances from a mere trace to several percent. Emplacement of the cupriferous basic rocks is predisposed to a large extent by enigmatic structural features locally referred to as steep structures. The most common manifestation of steep structure deformation is typically a narrow antiformal linear feature along which continuity of the country rocks has been interrupted by piercement folding and shearing. In places, pipelike bodies of megabreccia occur along steep structures, and also act as hosts to the basic rock. Areas of steep structure are thus prime exploration targets, due to their close spatial association with the cupriferous basic rocks. Exploration techiques employed in the Okiep Copper District in~ elude regional and detailed geological mapping, geophysical surveys utilizing magnetic, gravimetric and electrical methods, as well as limited application of soil and stream-sediment geochemistry. Final evaluation is by surface and underground diamond drilling. Exploration has to date discovered 18 new mines with individual ore reserves ranging from 200 000 to 37 000 000 tonnes. All are underground operations, and the sub-level open stoping method of mining is standard.

D.Phil. (Geology) / Please refer to full text to view abstract

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The strained commodity price environment has triggered strong measures of cost containment and control by global and South African mining industries with workforce reductions, mine closures and shelved projects. Added to this, the South African mining industry is facing an unparalleled number of challenges, including an uncertain regulatory environment, infrastructure constraints, frequent industrial actions, rising costs and shortages of skills. The dynamism of discontinuous change has increased considerably and the South African mining industry is today facing an uncertain future with a blurred outlook. The results of the detailed analysis of future studies theory and practice in this research study support the argument that there is a strong need to fundamentally change the ways of planning for the future of the South African mining industry. The practice of developing new insight through the application of futures studies is central to this process. Today, collective decisions and strategies are progressively more founded on and informed by futures studies. The research study sought to develop insight regarding the future of the South African mining industry through the construction of four scenarios towards 2055: Divided We Fall, where a confident industry is threatened by social divisions as industry transformation is disregarded; Rock Bottom, where weak global economic conditions coincide with lacklustre industry innovation; Rising from Ashes, with similar economic conditions, but the industry responding positively through accelerated industry innovation; and Renaissance, set against positive global economic conditions with the South African mining industry adopting a collaborative, innovative approach to industry transformation. The research study further strived to uncover the preferred future for the South African mining industry as basis for the South African Mine of the Future Vision towards 2055. Throughout the research study, Inayatullah’s pillars of futures studies were applied as a guideline in mapping the present and future, deepening the future, broadening the future through the development of scenarios, and transforming the future by narrowing it down to the preferred. The study provides valuable insight into the driving forces relevant to the South African mining landscape. In addition, it provides insight on how to anticipate the changes these driving forces may bring about for the industry over the next 40 years from a decision-maker’s point of view. It is up to the mining industry to select the road to follow in terms of progress and sustainable development. Through an innovative approach, the creation of an environment of trust, the sharing of values, purposes and benefits, the South African Mine of the Future Vision is attainable. The South African mining industry must commit itself to working in collaborative partnerships with local communities, government, society and labour; stepping boldly into a world of social, environmental, technological and commercial innovation.

M.Sc. (Geology) / The Witwatersrand Supergroup is host to a number of auriferous and uraniferous conglomeratic reefs, which have been extensively exploited along the Witwatersrand Basin margins. The current study investigates the Vaal Reef, in the Klerksdorp gold field with particular focus on conducting a geometallurgical characterization of the ore which may ultimately enhance the recovery of gold and uranium and our understanding of how the ore responds to processing. Six samples were collected from AngloGold Ashanti’s Moab Khotsong mine and prepared for a chemical and mineralogical deportment study. These samples were milled and crushed down to 80% passing -75μm and processed for head chemistry assays, grading analysis as well as heavy liquid separation analysis as part of the chemical deportment. The samples were also submitted for gold cyanide, acid uranium and diagnostic leach tests.....