Witwatersrand basin pdf files

Today the greater witwatersrand basin encompasses a semicircular arc of 440 kilometers and includes 7 separate goldfields. Mossman department of geography and environment, mount allison university, sackville, new brunswick e4l 1a7, canada email. Abstract historically, there have been a range of diameter estimates for the large, deeply eroded vredefort impact structure within the witwatersrand basin, south africa. An outlier, separated by structural deformation occurs 40 miles east of the main basin outcrop, whereas the outlier is entirely covered by younger rocks. 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. The worlds 10 most prolific gold fields march 31st, 2011. The mesoarchaean witwatersrand basin represents the largest known gold anomaly and has produced more gold than any other ore province in the world. Largest gold deposits in the world witwatersrand gold fields.

Viljoen department of geology, university of the witwatersrand figure 1. Pdf the worlds greatest deposit of gold is hosted by the archaean witwatersrand sedimentary basin, situated in the central portion of the kaapvaal. Pdf secondary minerals from the carletonville gold mines. Gold mining is currently confined to narrow conglomerate reefs and carbon seams in the upper. Pdf the witwatersrand basin in south africa has been the focus of gold exploitation for more than 100 years, and the subject of hundreds of. Some reference is also made concerning the research bodies that have provided the pivotal role needed in formulating mitigation strategies by turning data into knowledge. The university of texas at austin bureau of economic geology university station, box x austin, texas 7878924 512 8690390 email address. Witwatersrand basin the first discovery of gold in the region is recorded as being in 1852 in the pardekraal farm 1 by j. The depositional facies grade from braided fluvial arkoses, through tidal flat sediments to mature sandy shelf deposits that consist primarily of shales and carbonate shales. 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.

If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a pdf plugin installed and enabled in your browser. The mesoarchaean witwatersrand basin represents the largest known gold anomaly and has produced more gold. However, in its 3 billion years old geological history. The gold mines in this area are possibly the deepest mines in the world mining operations at 3600 m and exploration coredrilling up to 4600m. However, in its 3 billion years old geological history, the witwatersrand basin in south africa has been covered by seawater, but experienced also episodes of drying out, flooding and erosion by rivers and the repeated coverage by seawater. The discrimination made here was much more distinct than that made within the witwatersrand basin, and this is considered to be due to a single source of gold compared to possible multiple sources, as is the case in the witwatersrand basin. Pulses of sedimentation within the sequence and its precursors were episodic, occurring between 30863074 ma dominion group, 29702914 ma west. Economic geology research institute wits university. 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.

Here is an update report with the most recent news. Witwatersrand goldpyriteuraninite 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. Witwatersrand goldbearing reefs, and to present an objective and balanced overview of theories on the formation of the gold ores. The following are the supplementary data related to this article. The effects of uranium mining on health case studies. Aug 06, 2017 the witwatersrand basin in south africa is the single largest gold district in the world, having produced 1.

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. Geological framework and mineralization processes laurence j. Iaea 20 classification of uranium deposits the 20 iaea classification is a combination between the iaea classification used in the red book since 1991 and the dahlkamp 1993, 2009 classifications. Flooding commenced when the last mine 1 the environmental critical level is defined as the highest water level within the mine void where no amd. The witwatersrand basin in south africa is one of the bestpreserved records of fluvial sedimentation on an archaean continent 1. The gold in this basin occurs in the coarse grained conglomerates forming the upper portions of the witwatersrand supergroup that hosts roughly. Pyrite zoning as a record of mineralization in the. The witwatersrand basin is the largest goldfield in the world having yielded over 52,000 tonnes of gold 1,672 moz. Neoarchaean tectonic history of the witwatersrand basin and ventersdorp supergroup. The clastic sediments were derived from a mountainous source to the northnortheast of the basin button, 1986. Provenance of illicit gold with emphasis on the witwatersrand. The witwatersrand rocks overlie rocks of the dominion reef system, underlie those of the ventersdorp system, and occur in an eastwest band.

Sediments in the witwatersrand are believed to be sourced. Horscroft 22 ingram house, park road, hampton wick, surrey, kingstonuponthames, kt1 4ba, uk d. Mining seismicity in the witwatersrand basin africa array. Mponeng gold mine, witwatersrand basin south africa. Wits basin since inception the basin has yielded over 50,000 tons of gold. Abstract the witwatersrand basin formed over a period of 360 ma between 3074 and 2714 ma. Pdf evaluating the structural character and tectonic history of the.

It is estimated that an inferred resource of about 30,000 tonnes. Discover witwatersrand basin in hartbeespoort, south africa. The upper witwatersrand beds underlie an area of some 15,000 square miles in what is generally called the main witwatersrand basin. With our present knowledge we perceive the paleo witwatersrand as a basin surrounded by mountains of moderate height which were geologically. Flexural partitioning of the late archaean witwatersrand foreland. With both projects, great basin is coming very close to reaching their first objective, to become a low cost, midtier gold producer. The witwatersrand basin remains the worlds largest gold resource.

It was formed two billion years ago by the largest, and the oldest, meteorite to strike our planet. Publications from south african mine research final. The sga was founded in 1965 in heidelberg and the 2015 sga biennial meeting. Geological setting university of the witwatersrand.

The life, death and revival of the central rand goldfied m. The witwatersrand basin and its gold deposits springerlink. The fossil gold placers of the witwatersrand pdf paperity. Each mine within the witwatersrand basin extracts gold from one or more reefs, so the variation within. The witwatersrand rocks overlie rocks of the dominion reef system, underlie those of the ventersdorp system, and occur in an eastwest band from randfontein to springs and from the vaal river in the region of. Pdf deep subsurface microbial biomass and community. Gold has long been one of mankinds most prized possessions. Witwatersrand basin, johannesburg, south africa outcome worlds largest gold rush ever led to the eventual boer defeat in the second boer war 18991902, the loss of boer autonomy and selfgovernment, and total british rule in south africa. Witwatersrand system, major division of precambrian rocks in south africa the precambrian began about 3. 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. Please use one of the following formats to cite this article in your essay, paper or report.

Molecular evidence for microbiallymediated sulfur cycling in. Hydrocarbon gases in the witwatersrand basin, south africa. 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. Major geological features of the witwatersrand basin stripped of younger cover and showing major goldfields and main remaining deep and shallow gold resource paper 77. Visualizing the formation of uranium and gold ore related to. Witwatersrand basin, south africa, methanogens contribute witwatersrand basin was formed. Neoarchaean tectonic history of the witwatersrand basin. The life, death and revival of the central rand goldfied. The growth and concentration of uranium and titanium. Sediments in the basin include a lower flyschtype sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. Visualizing the formation of uranium and gold ore related to fossil hydrocarbons in the witwatersrand basin.

Molecular evidence for microbiallymediated sulfur cycling. The witwatersrand basin is approximatly 350 km long and 200 km wide. It holds the worlds largest known gold reserves and has produced over 1. Past approaches to deciphering the history of mineralization in the. The witwatersrand supergroup, a 7 km thick goldbearing quartzite conglomerate with interbedded carbonrich layers, was deposited in the witwatersrand basin of south africa between 3000 and 2700 ma fig. Sulfur isotopic evidence of microbial activity during deposition of a neoarchean shale and in modern deep groundwater, witwatersrand basin, south africa. Witwatersrand basin as well as in the paragenetic sequence of mineralization recognized within the conglomeratic ore bodies which host the economic. The witwatersrand basin is a largely underground geological formation which surfaces in the witwatersrand, south africa. Gold mineralization is mostly concentrated in conglomerate horizons, or reefs, and is tightly associated with pyrite. Progressive mining engineers and the origins of the south african state keith breckenridge please do not cite, this is a work in progress.

Witwatersrand gold rush wikimili, the free encyclopedia. Pdf integrated interpretation of 3d seismic data to enhance. Pdf the worlds greatest deposit of gold is hosted by the archaean witwatersrand sedimentary basin, situated in the central portion of the. Pdf gold mineralization within the witwatersrand basin.

At the hollister project in nevada, 146,501 tons of ore have been extracted from which 101,380. Its estimated that half of the worlds gold was mined from south africas golden arc. As exposed today, witwatersrand style gold has been mined over a 300 km by 150 km area to depths of up to 4 kilometers. The theme for this th edition is mineral resources in a sustainable world. Scientists were able to figure out how parts of the earths largest gold deposits. The viability of using the witwatersrand gold mine. Witwatersrand gold deposits formed by volcanic rain. Witwatersrand basin hartbeespoort, south africa atlas.

Integrated interpretation of 3d seismic data to enhance the detection of the goldbearing reef. A contribution to recent debate concerning epigenetic. Michael meyer i department of geology, university of the witwatersrand, private bag 3, wits 2050, south africa received 19 december 1994. Neoarchaean tectonic history of the witwatersrand basin and. The worlds greatest deposit of gold is hosted by the archaean witwatersrand sedimentary basin, situated in the central portion of the kaapvaal craton of south africa. 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. The archean metasedimentary succession of the witwatersrand basin, south africa, hosts the largest au deposit in the world. These dams are mostly unlined and many are not vegetated, providing a source of extensive dust, as well as soil and water surface and groundwater pollution anglogold ashanti, 2004.

Deep subsurface microbial biomass and community structure in witwatersrand basin mines. Mine water management in the witwatersrand gold fields with. 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. Molecular evidence for microbiallymediated sulfur cycling in the deep subsurface of the witwatersrand basin, south africa leah morgan senior integrative exercise march 10, 2004 submitted in partial fulfillment of the requirements for a bachelor of arts degree from carleton college, northfield, minnesota. Flooding commenced when the last mine 1 the environmental critical level is defined as the highest water level within the. Mine water management in the witwatersrand gold fields.

Durrheim a,c a school of geosciences, university of the witwatersrand johannesburg, pbag 3, wits, 2050, republic of south africa. However, it does show that hydrocarbon liquids may have played an important role in remobilizing uranium from detrital uraninite and concentrating it to potentially economic levels in the witwatersrand basin. It is the worlds largest gold and uranium mining basin with the extraction, from more than 120 mines, of 43 500 tons of gold in one century and 73 000 tons of. The pollution and destruction threat of gold mining waste on.

Mining gold today often becomes monumental undertakings, truly some of mans greatest engineering feats. The application of geophysics to gold exploration in south. The witwatersrand basin is the heart of south africaa gold mining industry. The cluster of gold mines located in the witwatersrand basin generates a significant amount of mine tailings, which have adverse effects on the environment and ecological systems. Yet most people have little idea where gold comes from, other than from gold mines. There are more than 270 tailings dams in the witwatersrand basin, covering approximately 400 km 2 in surface area anglogold ashanti, 2004. Witwatersrand basin hartbeespoort, south africa atlas obscura. The witwatersrand basin in south africa is the worlds largest gold province. Witwatersrand basin here has been the source of about one third to one half of the gold. Pulses of sedimentation within the sequence and its precursors were episodic, occurring between 30863074 ma dominion group, 29702914 ma west rand group and 28942714 ma central rand group. Witwatersrand basin have concentrated on the hostrocks within the depository.

He classified the ore genetic theories into three types. Apr 20, 2017 the witwatersrand basin in south africa hosts the largest known gold repository on earth but how was it formed. Map of the witwatersrand basin showing mining areas from which shales were collected for this study and stratigraphic column of the witwatersrand succession showing the horizons of sampled shales. Witwatersrand basin, which contains nearly half the worlds gold, covers an area the size of west virginia in the northeastern part of south africa. Witwatersrand mining basin the witwatersrand has been mined for more than a century.

Mining iron and phosphates the third lesson explores the history of iron extraction and how iron has been used in europe and the far east. Thermal properties of stratified rocks from witwatersrand. This supergroup overlies a 3400 ma granitegreenstone basement complex. Hydrothermal gold mineralization in the witwatersrand basin. The witwatersrand basin in south africa is the single largest gold district in the world, having produced 1. However, if the witwatersrand basin was formed significantly prior to 2 700 ma ago, it may be related to tectonism associated with the implacement. Download fulltext pdf secondary minerals from the carletonville gold mines. An oligotrophic deepsubsurface community dependent on. Superplume versus farfield stress as geodynamic controls on.

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