Controversies on the Origin of World-Class Gold Deposits, Part II
The Witwatersrand deposits are regarded as remnants of a gold megaevent at 2.9 Ga when environmental conditions are suggested to have been suitable for intense gold flux off the Archean land ...
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Witwatersrand gold particle chemistry matches model of
particles, the mean gold composition at a given reef lo-cality may be used to distinguish di•erent source areas of the originally detrital particles. Introduction The genesis of the world-famous gold deposits in the Late Archaean Witwatersrand Basin in South Africa has been a highly contested issue for almost as long as these deposits have ...
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(PDF) Witwatersrand Basin: A Goldfield Review
To form the enormous high grade gold deposits of the Witwatersrand, three critical elements were essential. There needed to be a source of gold, concentrating mechanisms and preservation events. The primary source for the Witwatersrand gold was the surrounding Archaean granite-greenstone terrain of the Kaapvaal Craton.
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The formation of gold deposits in South Africa | ScienceDaily
In 1852, the English prospector J.H. Davis discovered the first gold in the Witwatersrand, leading to the South African gold rush and the discovery of much more gold …
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(PDF) Witwatersrand composite paleoplacers
The Witwatersrand gold province located in South Africa is the richest in the world. The Witwatersrand deposits are composite, where osmirids and diamonds are mined along with gold, silver and ...
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The Formation of Gold deposits in South Africa
In 1852, the English prospector J.H. Davis discovered the first gold in the Witwatersrand, leading to the South African gold rush and the discovery of much more gold deposits within the basin. Although the Witwatersrand has been subject for decades of research, the genesis of gold and uranium ore is still unclear.
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Tectonics' bounty of gold
Earth's largest known gold source in the Witwatersrand Basin of South Africa formed at about 2.9–2.75 Ga. Dating shows the gold is older than other lithologies in the basin 6, but evidence ...
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Gold mineralization within the witwatersrand basin
The world-class Witwatersrand gold deposit in South Africa has produced some 50 000 tonnes of gold since mining began in the late 1880s (Robb & Robb 1998). The gold is mostly hosted by lower greenschist grade Archaean metasedim e …
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Seismic imaging of deep‐seated gold deposit and host rocks …
Seismic imaging of deep-seated gold deposit and host rocks through a reappraisal of legacy seismic data in the Fochville mining area, South Africa ... and it hosts almost more than 90% of the ore gold deposits found in the Witwatersrand Basin. On a regional scale, the Witwatersrand Supergroup is overlain by the Ventersdorp Supergroup, which is ...
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Witwatersrand gold deposits formed by volcanic rain, anoxic
Gold in the Witwatersrand is enriched to mineable concentrations in thin quartz pebble beds ('reefs') that commonly extend over kilometres.
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Chapter 31: Geologic Evidence of Syngenetic Gold in the Witwatersrand
Witwatersrand-type gold deposits are further characterised by the presence of carbonaceous matter in the conglomerate horizons, as seams and nodules (see England et al., 2002;Frimmel et al., 2005 ...
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Witwatersrand Gold Deposits
Here is some history of the Witwatersrand Gold Style Ore Deposits as they related to South Africa since the arrival of the Dutch and the …
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Largest Gold Deposits in the World – Witwatersrand Gold Fields
The gold fields of the Witwatersrand Basin in South Africa are, by a landslide, the largest single gold producing district in the world. It has produced some 2 billion ounces over a century of mining and at an average grade of 15 g/t Au with a current head grade of 6-10 g/t Au and they still have estimated reserves …
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Inhospitable climate fosters gold ore formation | ScienceDaily
The Witwatersrand Basin in South Africa holds the world's largest gold deposits across a 200-km long swathe. Individual ore deposits are spread out in thin layers over areas up to 10 by 10 km ...
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Witwatersrand gold deposits | Gold Bulletin
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 conditions under which they were formed. In particular they indicate that in some areas primitive plant life on the deltas on which the gold was deposited acted not only like the legendary golden fleece in concentrating …
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The Witwatersrand Basin and Its Gold Deposits
The Witwatersrand gold deposit is the largest in the world. Thermodynamic calculations show that such rich accumulations of gold could be linked to abundant volcanism, primitive life and the … Expand. 53. PDF. Save. Ages of altered granites adjoining the Witwatersrand Basin with implications for the origin of gold and uranium.
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Copper isotopic evidence of microbial gold fixation in the …
A comparison of the copper isotope composition of sedimentary rock strata spanning in age across the Great Oxidation Event (GOE) and that of pyrite, carbon, and native gold from the Mesoarchean Witwatersrand Basin reveal that an oxidative gradient triggered gold precipitation on biologic material, now present in the form of gold-rich carbon seams in the latter.
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(PDF) Witwatersrand Gold: Modified Placer Origins
The fact that the Witwatersrand-type gold deposits, a target for exploration, occur spatially and temporally within the Archaean/Palaeoproterozoic geological record demonstrates that the Witwatersrand Basin is not unique in terms of composition and paragenesis, but is unique in terms of physical size and magnitude of its gold and uranium ...
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Witwatersrand, Johannesburg (Gauteng)
Witwatersrand, ridge of gold-bearing rock mostly in Gauteng Province, South Africa.Its name means "Ridge of White Waters, in Afrikaans."The highland, which forms the watershed between the Vaal and Limpopo rivers, is about 100 km long and 37 km wide; its average elevation is about 1,700 meters. Its rich gold deposits, occurring in conglomerate beds known as reefs, were …
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The World's Richest Deposit of Gold
In 1886, after years of rumors, legends, and smaller discoveries, it was definitively established that there was a huge, rich deposit of gold under the Witwatersrand, a rocky ridge …
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[PDF] Witwatersrand gold deposits formed by volcanic rain, …
The Witwatersrand gold deposit is the largest in the world. Thermodynamic calculations show that such rich accumulations of gold could be linked to abundant volcanism, primitive life and the oxygen-free atmosphere of the Archaean. The Witwatersrand Basin in South Africa is one of the best-preserved records of fluvial sedimentation on an Archaean continent1. …
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The Witwatersrand Gold Rush: South Africa's Mining History
The Witwatersrand Gold Rush shows human dreams and luck in finding gold 1. Imagine a huge area in South Africa, 56 kilometres long. It goes up to 1,800 metres high 1. …
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Witwatersrand gold deposits formed by volcanic rain, anoxic …
hosted gold deposits, as erosional relics of a potentially much larger primary source of gold1,6. Gold in the Witwatersrand is enriched to mineable concentrations in thin quartz pebble beds ('reefs') that commonly extend over kilometers. These beds represent residual deposits on mature continental land surfaces, where river plains with gravels
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Models and Exploration Methods for Major Gold Deposit Types
new gold deposits. The objectives of this paper are to provide an update on gold deposit models, and what new approaches and techniques can now be used to find gold deposits. Gold occurs in a wide range of deposit types and settings, but this paper is concerned with deposits in which gold forms the main economic commodity or a co-product.
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The Witwatersrand Basin and Its Gold Deposits
Almost every imaginable genetic model has been proposed to explain the Witwatersrand gold deposits, ranging from syn-sedimentary placer to epigenetic magmatic or …
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The witwatersrand gold deposit, South Africa:: An impact-modified
The world-class Witwatersrand gold deposit in. South Africa has produced some 50 000 tonnes. of gold since mining began in the late 1880s (Robb & Robb 1998). T he gold is mostly hosted.
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Gold Deposits
Alluvial or Placer Gold Deposits 8. Witwatersrand-Type Deposits 9. Conclusions Acknowledgments Glossary Bibliography Biographical Sketches Summary Gold is a rare element in crustal rocks due to its generally chalcophile properties; it is increasingly enriched in mantle rocks and particularly the metallic core. In nature, gold
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THE NATURE OF THE WITWATERSRAND GOLD-URANIUM DEPOSITS …
The world's greatest deposit of gold is hosted by the Archaean Witwatersrand sedimentary basin, situated in the central portion of the Kaapvaal Craton of South Africa.
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Evolution of concepts on the origin of the Witwatersrand gold deposit
The placer and hydrothermal models of the origin of the Witwatersrand gold deposit differ in the interpretation of the degree of involvement of sedimentation and hydrothermal processes, as well as the source of gold. Analysis of the current data shows that the deposit hosts complex U-Au polygenous and polychronous mineralization. The primary ore-bearing material …
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