Flexural partitioning of the late archaean witwatersrand foreland. The witwatersrand mining basin is composed of the far east basin, central rand basin, western basin, far western basin, kosh and the free state gold mines a remotesensing and gisbased integrated approach for risk based prioritization of gold tailings facilities witwatersrand, south africa. Detection of potential methane gas pathways in deep south african. Geological society, london, special publications, 2005. Chlorite geothermometry, in conjunction with fluid inclusion microthermometry and the thermodynamic modeling of equilibrium mineral assemblages, was applied to siliciclastic rocks to set constraints on the geothermal gradients. Location and general geology karoo supergroup removed of the witwatersrand basin, south africa after mccarthy et a.
The witwatersrand basin of south africa is an elongate structure of archean age 2. Download full the geology of the witwatersrand book or read online anytime anywhere, available in pdf, epub and kindle. Discover witwatersrand basin in hartbeespoort, south africa. This elliptical basin stretches over an arc of roughly 400 km traversing across the free state, north west and gauteng provinces in south africa as shown in fig. The witwatersrand basin is part of a retroarc foreland system formed during the. However, in its 3 billion years old geological history.
Sediments in the basin include a lower flyschtype sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. Stable isotope composition of quartzcalcite veins in the. The gold ores of the witwatersrand basin figure 1, inset are no exception and contain elevated concentrations of lead pb, copper cu, nickel ni, cobalt co, zinc zn and uranium u, amongst others. The witwatersrand basin, south africa caracle creek. Mining has been taking place within the wbp area since the discovery of the goldfields in 1886. Gold mining in the witwatersrand basin has been responsible for the creation. Variables affecting the impact of acid mine drainage. Witwatersrand basin hartbeespoort, south africa atlas.
Geotechnical areas associated with the ventersdorp contact. Largest gold deposits in the world witwatersrand gold. Archean foreland basin tectonics in the witwatersrand. Witwatersrand basin is a classic example of where a variety of geological processes have coincided in time. Tectonosedimentary model for the central rand goldfield. The presence of kerogen and bitumen in the witwatersrand sedimentary rocks, together with a wealth of observations on the spatial distribution of the carbon seams. Bumby et al 1998 and hartzer 1995 recognised prebushveld deformation and that various transvaal supergroup sedimentary inliers may be floor projections. Neoarchaean tectonic history of the witwatersrand basin and ventersdorp supergroup. Witwatersrand basin are the worlds two largest precious metal ore deposits ryder and jager, 2002. Outside of the witwatersrand basin significant quantities of gold have been recovered from archaean greenstone belts of the 3500 to 2700 ma kaapvaal craton as well as from various occurrences in the 2600 to 2200 ma transvaal supergroup. Economic geology research institute wits university. Gold occurs most commonly as free gold and as inclu sions within.
Gold on the kaapvaal craton, outside the witwatersrand basin. Pdf gold mineralization within the witwatersrand basin. Download full witwatersrand book or read online anytime anywhere, available in pdf, epub and kindle. The basin is located in the northeastern part of the republic of south africa, within the provinces of the transvaal and the orange free state. Chlorite thermometry in the witwatersrand basin jstor. Photomicrographs of gold grains from witwatersrand basin deposits, south africa. Gold accumulation in the archaean witwatersrand basin, south. The application of geophysics to gold exploration in south. Archean foreland basin tectonics in the witwatersrand, south africa. The low ph associated with amd enhances the mobilisation of these metals, resulting in their. The witwatersrand basin of south africa is the best.
The witwatersrand basin is roughly oval in shape, approximately 350km in a north east to south west direction and stretching over 150km across fig. Gold on the kaapvaal craton, outside the witwatersrand. Schweitzer synopsis the approximately 2800 ma old ventersdorp contact reef is a unique witwatersrand orebody, from which about 6% of the worlds gold production is derived. Pdf gold mobilizing fluids in the witwatersrand basin. Horscroft 22 ingram house, park road, hampton wick, surrey, kingstonuponthames, kt1 4ba, uk d. Thus the witwatersrand is apparently unique because two unusual factors combined. Archean foreland basin tectonics in the witwatersrand, south africa the witwatersrand basin of south africa is the bestknown of archean sedimentary basins and contains some of the largest gold reserves in the world. The western faultbounded boundary of the witwatersrand basin is 200km long pretorius, 1974 to zero at the pole or vertex of opening in the evander region the eastcurved colesberg linear or asperity favours releasing bend over the witwatersrand basin the regressive hinge migration south in southern orocline is at least 200km. We cannot guarantee that witwatersrand book is in the library. The witwatersrand basin of south africa is an elongate structure of archean.
Similar to the west rand group, this group is composed of a series of cycles, each comprising fluvially dominated coarse grained siliciclastics overlying an. Pdf the geology of the witwatersrand download full. Then, an example is reported by gartz and frimmel 1999 of bitumennodulesinveinswhichcrosscutpseudotachyliteattributable to the vredefort impact event in the ventersdorp contact reef. These are locally, in the northwestern part of the basin, underlain by the. The mines were located in the witwatersrand basin and the bushveld igneous complex, south africa figure 1. Superplume versus farfield stress as geodynamic controls on. In the 1980s a detailed thermal investigation of the witwatersrand basin was conducted by the university of the witwatersrand wits in collaboration with the. Create free account to access unlimited books, fast download and ads free. The witwatersrand basin is the worlds oldest wellpreserved sedimentary basin and has been the worlds largest gold producer. The impact of gold mining on the witwatersrand on the. We cannot guarantee that the geology of the witwatersrand book is in the library. Neoarchaean tectonic history of the witwatersrand basin and. Geological setting university of the witwatersrand.
Click get books and find your favorite books in the online library. Ifthemine designation is followed by a number, it indicates the number of. The upper witwatersrand beds underlie an area of some 15,000 square miles in what is generally called the main witwatersrand basin. These data when considered together with earlier total conglomerate upb analyses from the dominion reef supergroup lead to the conclusion that the uraniferous minerals of the dominion reef, witwatersrand, ventersdorp and transvaal. Archean foreland basin tectonics in the witwatersrand, south. A major portion of this production is mined at depths exceeding 2500 m and deepest levels of mining are at. Mossman department of geography and environment, mount allison university, sackville, new brunswick e4l 1a7, canada email. The application of geophysics to gold exploration in south africa. Concerning syndepositional origin of some witwatersrand car. Neoarchaean tectonic history of the witwatersrand basin. These data, supplemented by oxygen isotope analyses of hydrothermal quartz and in. Pdf the mine woodlands project in the witwatersrand basin.
The witwatersrand mining basin is composed of the far east basin, central rand basin, western basin, far western basin, kosh and the free state gold mines. Tectonic setting of the witwatersrand basin modified from robb et al. Bumby et al 1998 and hartzer 1995 recognised prebushveld deformation and that various transvaal supergroup sedimentary inliers may be floor projections or domes resulting from prebushveld interference folding northwest and east. Samples from the upper witwatersrand of the orange free state give 207 pb 206 pb ages of ca. Superplume versus farfield stress as geodynamic controls. Pdf the witwatersrand basin in south africa has been the focus of gold. The main reef, main reef leader and composite reef. A remotesensing and gisbased integrated approach for risk based prioritization of gold tailings facilities witwatersrand, south africa.
Witwatersrand basin worlds biggest gold deposits produced over 40% of all gold 6 witwatersrand basin and the pilbara pilbara conglomerate hosted gold the gold rush of the 21st century for personal use only an exciting new province. The basin is represented by a 5 to 8 km thick succession of mostly clastic sediments divided into two main groups, namely the lower west rand group and the overlying central rand group. For both reasons, the basin has been the subject of intensive study. The nature of the western margin of the witwatersrand basin core. Crushleach data were obtained, using high performance gradient ionchromatography and capillary electrophoresis, on individual generations of aqueous fluid inclusions in hydrothermal quartz from three different auriferous conglomerate horizons reefs in the late archaean witwatersrand basin, south africa. Herein, the mines are designated as beatrix be, driefontein dr, evander ev, kloof kl, merriespruit ms, mponeng mp, masimongmm,tautonattandnorthamno. The basin straddles the old provinces of transvaal and the orange free state, and consists. Although the free state mines are within the witwatersrand basin, the close proximity of overlying coal seams differentiates them from most of the other high occurrence reporting gold mines. Within the basin, gold is found within horizons of conglomerates, also known as reefs. Shandthe pseudotachylyte of parijs orange free state and its. Educational media international, inc gazelle film productions a detailed geological history of the development of the lower proterozoic basin and the deposition of the famous gold and uraniumbearing quartz. Agangi and others published gold accumulation in the archaean witwatersrand basin, south africa evidence from concentrically laminated pyrite find, read and. For report purposes the witwatersrand gold mines are those between evander and klerksdorp. The witwatersrand basin and its gold deposits springerlink.
Mining has been taking place within these areas since discovery of the. Transvaal and orange free state have produced more than 55 percent of. Pdf evaluating the structural character and tectonic history of the. It contains and is overlain by four precambrian volcanosedimentary sequences, the dominion group, the witwatersrand supergroup, the ventersdorp. Alluvial fans in general are a rather uncommon environment for gold concentration. The witwatersrand basin project wbp comprises two historic mining centres on the northern edge of the witwatersrand basin in the central rand goldfield immediately southwest of the city of johannesburg.
Most of the mining activity in the east and central rand occurred between. Witwatersrand basin and bushveld complex and emerging technologies to manage the risk of rockbursting by r. Weiersbye ecological engineering and phytotechnology programme, school of animal, plant and environmental science, university of the. Educational media international, inc gazelle film productions a detailed geological history of the development of the lower proterozoic basin and the deposition of the famous gold and uraniumbearing quartzpebble conglomerates. An outlier, separated by structural deformation occurs 40 miles east of the main basin outcrop, whereas the outlier is entirely covered by younger rocks. Helena gold mine in the orange free state have lead. The witwatersrand basin project wbp comprises two historic mining centres known as the durban roodepoort deep and the rand leases on the northern edge of the witwatersrand basin in the central rand goldfield immediately southwest of the city of johannesburg figure 1. These deposits are inclined hard rock narrow tabular orebodies that extend over vast lateral extents and exceptional mining depths ryder and jager, 2002.
This study concentrates on three broad areas of basin analysis and sedimentary geology, to ascertain the controlling factors determining uniqueness of the witwatersrand basin i. The witwatersrand basin is a largely underground geological formation which surfaces in the witwatersrand. Determination and modelling of geochemical speciation of. The mesoarchaean witwatersrand basin represents the largest known gold anomaly and has produced more gold. The geochemistry of pseudotachylyte and its host rocks from the. The witwatersrand basin formed over a period of 360 ma between 3074 and 2714 ma. It holds the worlds largest known gold reserves and has produced over 1. West wits mining limited wwi or the company has released an. One property of the basin fill that has become apparent is that the clastic sediments are compositionally supermature. Quartzpebbleconglomerate gold deposits usgs publications. The witwatersrand basin fill was subjected to a series of alteration events, ranging from burial and regional lowgrade metamorphism to heating in the course of the emplacement of the 2054 ma bushveld igneous complex and catastrophic shattering during the 2023 ma vredefort impact, which enabled renewed fluid flow long after primary rock. Central rand group which is up to 2880 m thick in the central part of the basin around the vredofort structure and unconformably overlies the west rand group, covering an area of 9750 sq. Witwatersrand gold deposits formed by volcanic rain, anoxic rivers. 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 basin hartbeespoort, south africa atlas obscura. Brink synopsis the seismicity of the witwatersrand basin and bushveld complex has been analysed, revealing significant differences in source and damage mechanisms. Details of the selected sites are given in table 1. Pdf the worlds greatest deposit of gold is hosted by the archaean witwatersrand sedimentary basin, situated in the central portion of the kaapvaal. The witwatersrand basin however, remains unique in terms of its mineral wealth. Very little gold has been found in younger formations.
Gold accumulation in the archaean witwatersrand basin. The witwatersrand basin is one of the oldest wellpreserved stratified basins on earth, its presentday perimeter approximately being defined by the distribution of major gold mines figure 1. The witwatersrand basin is renowned for its gold production whereas the bushveld complex is. Pdf the geology of the witwatersrand download full ebooks. Its estimated that half of the worlds gold was mined from south africas golden arc. The witwatersrand basin of jr south africa is the bestknown of archean sedimentary basins and contains some of the largest gold reserves in the world. Thermal properties of stratified rocks from witwatersrand. Some materi als associated with the witwatersrand gold give ages older than the host conglomerates whereas others give younger ages. The witwatersrand basin hosts some of the largest and dee. Several investigations conducted between the late 1930s and late 1970s, for both geodynamic reasons and mine engineering purposes, established an initial database of rock thermal properties16.
A large proportion of the coal deposits and all of the gold deposits lie within the vaal river catchment. The effects of uranium mining on health case studies. Sediments in the basin include a lower flyschtype sequence and an upper molassic facies, both of which contain abundant silicic. Attenuation of pollution arising from acid mine authors. Transvaal crustal thickening, burial metamorphism and hydrothermal infiltration during crustal thinning and associated deposition of the 2. Durrheim a,c a school of geosciences, university of the witwatersrand johannesburg, pbag 3, wits, 2050, republic of south africa. The witwatersrand deposits occur in six alluvial fans disposed on an arcuate margin of the witwatersrand basin figure 1, right. Gold mineralization within the witwatersrand basin, south africa. Water balance determination in mine residue deposits. Witwatersrand basin is one of the betterstudied regions in the world from a geothermal perspective. The effects of uranium mining on health case studies from. Most of the mining activity in the east and central rand occurred between 1886 and the early 1970s, with.
Driefontein no 3a and old north complex no 3 tailings dams. The kopanang waste rock dump is approximately 80 m high and located at no. The witwatersrand basin in south africa is one of the bestpreserved records of fluvial sedimentation on an archaean continent. Pulses of sedimentation within the sequence and its precursors were episodic, occurring between 30863074 ma dominion group, 29702914 ma west rand. Complex and emerging technologies to a manage the risk of.
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