Pressure, temperature, and timing of mineralization of the sedimentary
This, together with fluid–rock interaction, and a decrease in fO2 lead to sulfide and gold precipitation at Klipwal. Re-Os data from six sulfide samples constrain the age of sulfide precipitation and, by inference, gold mineralization, to 2563 ± 84 Ma, with an initial 187Os/188Os = 0.29 ± 0.08 (MSWD = 0.38).
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Genesis of the White Mountain Gold Deposit, Jilin
White Mountain is a sedimentary rock-hosted gold deposit located in the Hunjiang basin along the northeastern margin of the North China block in Jilin Province, China. With a premining endowment of 1.86 million ounces (Moz) Au at an average grade of 3.24 g/t Au, White Mountain is the largest gold deposit in the mineral-rich basin.
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The Formation of Gold deposits in South Africa
At a first glance, the Witwatersrand basin, the largest known gold resource on our planet, is not automatically related to ocean research. However, in its 3 billion years old geological history, the Witwatersrand basin in South Africa has been …
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Quartz-Pebble-Conglomerate Gold Deposits
Cover. Sheared pyrite in a mylonitic contact between the Ventersdorp Contact Reef (main part of photograph) and the Ventersdorp lavas (uppermost part of photograph) at the Vaal Reefs mine in the Klerksdorp Gold Field, Witwatersrand, South Africa.
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The Witwatersrand Basin, South Africa: Geological framework …
The Witwatersrand Basin of South Africa is the best-known of Archean sedimentary basins and contains some of the largest gold reserves in the world. Sediments in the basin include a lower flysch-type … Expand
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Gold accumulation in the Archaean Witwatersrand Basin, South Africa
The analysis of multiple S isotope ratios in pyrite has proven to be a powerful tool in the study of ancient rock successions, especially since it was discovered that sedimentary rocks older than c. 2.3 Ga show mass-independent S isotope fractionation, which is interpreted to be the result of photochemical reactions distinctively occurring in the early atmosphere (Thiemens, …
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Gold deposits – where they can be found and why
Limestone is a sedimentary rock made up of the calcium-carbonate shells of tiny, long-dead marine animals. The convective flow patterns you see in Cream of Wheat and in gold concentration processes are called hydrothermal cells. For gold these cells can be vast in size, stretching more than 10 kilometers across.
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Archaean lode gold mineralisation in banded iron formation at the
The ~3033 Ma Stella layered intrusion is hosted by supracrustal rocks of the Kraaipan–Madibe greenstone terrane, South Africa. The studied portion of the intrusion consists mainly of magnetite ...
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The Formation of Gold deposits in South Africa
At a first glance, the Witwatersrand basin, the largest known gold resource on our planet, is not automatically related to ocean research. However, in its 3 billion …
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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. ... Layers of sedimentary rock in the Witwatersrand show that is was once a shallow sea. This sea was formed approximately 3 billion years ago after the collision between the Zimbabwe and Kaapvaal cratons ...
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Genesis of life: the ancient tale of the
J J ust south of the town of Barberton, in the beautiful province of Mpumalanga, lie the oldest and best-preserved sequence of volcanic and sedimentary rocks in the world. Known as ' the Genesis of Life ', the Makhonjwa Mountains are on their way to becoming a Un World Heritage Site.. Maybe you ' ve heard of Maropeng, the stunning Visitor Centre at the Cradle of Humankind …
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The formation of gold deposits in South Africa | ScienceDaily
The Witwatersrand basin in South Africa hosts the largest known gold repository on Earth -- but how was it formed? Scientists were able to figure out how parts of the Earth's …
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Gold : Mineral | Properties, Formation, Mining, Occurrence, Uses
Gold is often found associated with other mineralsin nature. Some common gold-associated minerals include: 1. Quartz: Quartz is a common mineral that is often associated with gold. It can occur in various forms, such as veins, stockworks, or as host rock in gold-bearing deposits. Quartz can serve as an indicator mineral for t…
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Gold Fields
The gold is mainly of detrital origin, deposited syngenetically with the conglomerates and interrelated with sedimentary features such as unconformities and fluvial channels.
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Category : Sedimentary rocks in South Africa
Media in category "Sedimentary rocks in South Africa" The following 5 files are in this category, out of 5 total. Auriferous, pyritic, quartz-pebble conglomerate (gold ore) (Vaal Reef, Witwatersrand Supergroup, Neoarchean, 2.76-2.89 Ga; Stilfontein Mine, North West Province, South Africa) ().jpg 1,336 × 909; 1.24
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Archaean atmospheric evolution: evidence from the Witwatersrand gold
The Witwatersrand gold fields in South Africa, the world's largest gold-producing province, play a pivotal role in the reconstruction of the Archaean atmosphere and hydrosphere. ... in which auriferous fluids were introduced from an external source into the host rock succession after sediment deposition. In contrast, those arguments, used in ...
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Background concentrations of gold in different rock types
The abundance of gold in crustal rocks is an important constraint on the formation of gold deposits. Gold concentrations in unmineralised igneous, sedimentary and metamorphic rocks range from 0.05 ...
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Seismic imaging of the gold deposit and geological structures …
The BLR remains the least explored gold deposit in South Africa, although it was discovered in the 1880s (Penning, 1891). The Chuniespoort Group (2.06–2.04 Ga; Eriksson et al., 2006 ) consists of dolomites (Malmani Subgroup), chert, limestones, shales and banded iron formations (Walraven, 1995 ).
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The Witwatersrand Basin, South Africa: Geological framework …
The third global episode of orogenic gold-vein formation occurred at ca. 2.1–1.8 Ga, as supracrustal sedimentary rock sequences became as significant hosts as greenstones for the gold ores. Greenstone–sedimentary rock sequences now exposed in interior Australia, northwestern Africa/northern South America, Svecofennia, and the Canadian ...
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Pressure, temperature and timing of mineralization of …
Pressure, temperature and timing of mineralization of the sedimentary rock-hosted orogenic gold deposit at Klipwal, southeastern Kaapvaal Craton, South Africa August 2015 Mineralium Deposita 50(6)
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Lithostratigraphy of the Sinqeni Formation, Pongola Supergroup, South
Council for Geoscience, 139 Jabu Ndlovu Street, Pietermaritzburg, 3200, South Africa e-mail: [email protected]
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Pressure, temperature, and timing of mineralization of the sedimentary
Miner Deposita DOI 10.1007/s00126-014-0573-9 ARTICLE Pressure, temperature, and timing of mineralization of the sedimentary rock-hosted orogenic gold deposit at Klipwal, southeastern Kaapvaal Craton, South Africa Sakthi Saravanan Chinnasamy & Ron Uken & Jürgen Reinhardt & David Selby & Spencer Johnson Received: 3 March 2014 / Accepted: 23 ...
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Gold mineralization within the Witwatersrand Basin, South Africa
The chemical composition of gold within the Archaean metasedimentary rocks of the Witwatersrand Supergroup displays significant heterogeneity at the micro-, meso and regional scales.
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Multiple sulphur isotope record of Paleoarchean sedimentary rocks
This study presents multiple sulphur isotope (32 S, 33 S, 34 S, 36 S) data on pyrites from silicified volcano-sedimentary rocks of the Paleoarchean Onverwacht Group of the Barberton greenstone ...
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Gold Deposits | Gold.info
Here the gold concentration lies between 1 and 10 grams of gold per tonne of rock. The most important deposits of this type are found in Papua New Guinea, New Zealand, Peru, Romania and Mexico. Witwatersrand Gold Deposits. A special type of gold deposit is the Witwatersrand goldmine in South Africa, which is by far the biggest gold field in the ...
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Archaean atmospheric evolution: evidence from the Witwatersrand gold
The Witwatersrand gold fields in South Africa, the world's largest gold-producing province, play a pivotal role in the reconstruction of the Archaean atmosphere and hydrosphere. ... Only in marine sedimentary rocks, such as shales in the West Rand Group, are Fe-oxides (predominantly magnetite) found instead of pyrite (Frimmel, 1996). Locally ...
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Where gold is currently mined
South Africa's gold ore reserves in the Witwatersrand Basin, a gold placer deposit, with gold hosted by conglomerates and grits, has been mined for more than 100 years but remains the greatest unmined source of gold in the world. …
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A Major Archean, Gold- and Crust-Forming Event in …
The WSG, located in the Kaapvaal craton of South Africa (fig. S1), composes an ∼7-km-thick sequence of detrital terriginous sediments (2, 10) derived from the erosion of older granite-greenstone belts in fluvial deltaic …
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