The worlds most important gold district is the witwatersrand, transvaal, south africa, which, however, only rarely produces crystalline material. Models and exploration methods for major gold deposit types robert, f. Witwatersrand mountain ridge, south africa britannica. It holds the worlds largest known gold reserves and has produced over 1. It has produced some 2 billion ounces over a century of mining and at an average grade of 15 gt au with a current head grade of 610 gt au and they still have estimated reserves of some 1,161 billion ounces. Exploration is mainly preoccupied with defining the footprints of known gold deposits and with integrating various techniques with geology for their efficient identification and detection. Nov 14, 2016 the gold fields of the witwatersrand basin in south africa are, by a landslide, the largest single gold producing district in the world. Department of geology, rand afrikaans university, johannesburg, south africa the witwatersrand deposits, which contain the largest known gold and uranium accumulations on earth, are located within a basinshaped sequence of sedimentary rocks. Witwatersrand gold pyriteuraninite deposits do not support a reducing archean atmosphere evolution of early earths atmosphere, hydrosphere, and biosphere constraints from ore deposits origin of hydrothermal fluids and gold mineralization associated with the ventersdorp contact reef, witwatersrand basin, south africa. Structural controls on witwatersrand gold mineralization. Department of geology, rand afrikaans university, johannesburg, south africa. Gold mineralization within the witwatersrand basin, south africa. Gold mineralization within the witwatersrand basin, south.
Apr 20, 2017 at a first glance, the witwatersrand basin, the largest known gold resource on our planet, is not automatically related to ocean research. Witwatersrand, ridge of goldbearing rock mostly in gauteng province, south africa. Discover witwatersrand basin in hartbeespoort, south africa. Ser thesis submitted for the degree of doctor of philosophy at the university of the witwatersrand, johannesburg january, 1969.
Onset of crustal gold cycle triggered by first oxygenic. Request pdf gold mineralization within the witwatersrand basin, south africa. Mode of deposition and timing of witwatersrand gold mineralization has been a source of extreme controversy. Hydrothermal gold mineralization in the witwatersrand. Epithermal gold deposit model showing spatial relationship between low and highsulfidation epithermal mineralization with porphyry copper and intrusion. One of the main problems in understanding the origin of the witwatersrand basin mineralization concerns the source of the prodigious concentrations of gold and uranium in the basin. The xrays anu scattered radiation trom the rock matrix are detected cy. Ages of altered granites adjoining the witwatersrand basin. Nov 03, 2014 ore deposit is a natural concentration of one or more minerals within the host rock. Macdonald i, boyce aj, butler ib, herrington rj, polya da eds mineral deposits and earth evolution.
Quartzpebbleconglomerate gold deposits usgs publications. The gold fields of the witwatersrand basin in south africa are, by a landslide, the largest single gold producing district in the world. The origin of gold in south africa ancient rivers filled with gold, a spectacular upwelling of magma and a colossal meteor impact combined to make the witwatersrand basin a very special place jason kirk, joaquin ruiz, john chesley and spencer titley perfectly understood and the ideas about how all this gold came to be here are quite controversial. Introduction the gold fields of the witwatersrand basin in south africa are, by a landslide, the largest single gold producing district in the world. The witwatersrand is a large basin of metamorphosed conglomerates that forms the greatest goldfield in the world. Because the gold ore in the witwatersrand basin is located in ore reefs, these deposits have also been coined quartzpebble reef deposits.
Hydrothermal gold mineralization in the witwatersrand basin nature. In burkina faso studies completed by feybesse et al. However, in its 3 billion years old geological history. Here we present the results of an extensive geological study of witwatersrand rocks which show that the gold and associated uranium. Upb detrital zircon shrimp, and is made up of coarse clastic. Largest gold deposits in the world witwatersrand gold fields. Neoarchaean tectonic history of the witwatersrand basin and. Gold is relatively scarce in the earth, but it occurs in many different kinds of rocks and in many different geological environments. Evidence for a modified placer origin, and the role of the vredefort impact event the chemical composition of gold. The witwatersrand basin is a largely underground geological formation which surfaces in the witwatersrand, south africa. Visualizing the formation of uranium and gold ore related to fossil hydrocarbons in the witwatersrand basin. It stretches for 350 km long by 200 km wide with a thickness that can exceed.
Jul 11, 2014 as a partial answer to whether or not gold mineralization in the pilbara basin can be compared to that of the witwatersrand basin, this is what dr. Michael meyer i department of geology, university of the witwatersrand, private bag 3, wits 2050, south africa received 19 december 1994. Two notable observations were made during the deportment study, both relating to the style of mineralization at beatons creek. Models and exploration methods for major gold deposit types. Hayward cl, reimold wu, gibson rl, robb lj 2005 gold mineralization within the witwatersrand basin, south africa. Significance of granitegreenstone terranes in the formation. The fossil gold placers of the witwatersrand pdf paperity. The witwatersrand basin is the largest goldfield in the world having yielded. Metal anomalies pathfinders for gold exploration using thermo scientific portable xrf analyzers example from the blackwater gold deposit, british columbia, canada figure 1. The gold mineralization was formed under conditions of partially closed systems, where various mineralforming processes developed metasomatism. Neoarchaean tectonic history of the witwatersrand basin. Please use one of the following formats to cite this article in your essay, paper or report.
South africa has produced some 50 000 tonnes of gold since mining began in the late 1880s. Hydrothermal gold mineralization in the witwatersrand basin. Recycling of witwatersrand sediments corroborates with the primary mechanism of gold concentration in the black reef formation, and thus serves to establish multiple lines of evidence that favours the mechanical concentration of gold from granitegreenstone terranes and gold rich clastic sequences into the younger sedimentary succession. Witwatersrand basin hartbeespoort, south africa atlas obscura.
The highland, which forms the watershed between the vaal and limpopo rivers, is about 62 miles 100 km long and 23 miles 37 km wide. Temporal distribution of orogenic gold deposits is closely linked with periods of enhanced crustal growth between 2. The witwatersrand basin and its gold deposits springerlink. Its estimated that half of the worlds gold was mined from south africas golden arc. Largest gold deposits in the world witwatersrand gold fields, 14 nov 2016. Geological framework and mineralization processes laurence j. Studies of the morphology and other properties of the gold particles in the fossil placer gold deposits of the witwatersrand provide fascinating glimpses of the. The witwatersrand deposits, which contain the largest known gold and uranium. Proterozoic boundaries on a global scale and highlighted the witwatersrand gold uranium mineralization and the iron ore deposits of west africa, specifically mauritania and liberia. Structural controls on the distribution of gold in the witwatersrand basin can be seen at scales ranging from that of thin sections up to regional seismic data sets. Structural controls on witwatersrand gold mineralisation. Visualizing the formation of uranium and gold ore related to.
In south africa, witwatersrand type gold, pyrite, and uranium mineralization is sporadically represented over a considerable period of time from local occurrences in the archean greenstone basement, through the dominion reef, witwatersrand supergroup, and black reef formation of the transvaal sequence. Explorer and prospector jan gerrit bantjes 18401914 was the first and original discoverer of a witwatersrand gold reef in june 1884 having prospected the area since the early 1880s, as well as cooperating the kromdraai gold mine in 1883 to the nw of presentday johannesburg together with his partner johannes stephanus minnaar in an area. Gold mineralization within the witwatersrand basin. Pdf gold mineralization within the witwatersrand basin. At the thin section scale, gold occurs largely in fractures with hydrocarbons. India, and west australia, with a particular emphasis derry 1961 considered archeanon gold and copper. The origin of the gold mineralization in the witwaterstrand basin of south africathe largest known gold provincehas been controversial for decades, with arguments favouring detrital1,2.