The Witwatersrand Basin and Its Gold Deposits

Frimmel, Hartwig E.

doi:10.1007/978-3-319-78652-0_10

Cited by 32 publications

(17 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(e.g. Frimmel, 2019;Kositcin and Krapež, 2004). However, there is evidence of glaciation on the Kaapvaal Craton during that time interval, very well-documented in the 2.94-2.87 Ga Mozaan Group in Kwazulu-Natal by Young et al (1998) and correlated with the Witwatersrand Supergroup by Beukes and Cairncross (1991).…”

Section: Sediment Transport By Water or Ice?mentioning

confidence: 96%

Dating detrital zircon from the gold-bearing Ventersdorp Contact Reef in the Ventersdorp Supergroup of South Africa

Cornell

Meintjes

Westhuizen

et al. 2021

Precambrian Research

View full text Add to dashboard Cite

The Ventersdorp Contact Reef (VCR) at the base of the >4.5 km-thick volcanosedimentary Ventersdorp Supergroup unconformably overlies the Witwatersrand Supergroup and is the second youngest mineable reef in the Witwatersrand Goldfields. The volcanic rocks of the Ventersdorp Supergroup are predominantly mafic, affected by low-grade thermal metamorphism and difficult to date. Only the Makwassie Formation in the upper Platberg Group of the main Ventersdorp repository has been reliably dated on four felsic volcanic samples at 2720 ± 2 Ma. The actual timing of Ventersdorp volcanism and the duration of the three recognised lithostratigraphic groups remains enigmatic, despite much research and heroic attempts to synthesize the available data.In this work detrital zircon grains from VCR conglomerates were U-Pb dated in order to improve the time constraints on the Klipriviersberg Group at the base of the Ventersdorp Supergroup. The six youngest grains in VCR samples were reliably dated at 2799 ± 9 Ma. The Klipriviersberg Group and the Ventersdorp Supergroup is thus younger than 2808 Ma and the supergroup is older than the 2642 Ma Vryburg Formation at the base of the Transvaal Supergroup.Comparisons of detrital grain dates confirm that the VCR was largely derived from erosion products of the underlying Witwatersrand Supergroup, however the youngest VCR grains are ~20 Ma younger and may have been derived directly from magmatic rocks in the provenance or a felsic facet of the synchronous komatiitic Klipriviersberg volcanism.Multi-grain analyses of discordant grains show that recent lead loss is predominant. However about 5% of the data show the effect of complex Mesoproterozoic lead loss, which can yield ages as much as 150 Ma too young in 10% discordant data. This was found in grains with high Th-induced radiation damage, providing a criterion for data rejection.The proposed large igneous provinces dated between 2791 and 2683 Ma, based mainly on dated mafic dykes, which are not in contact with supracrustal Ventersdorp rocks, do fit the established time constraints and might provide a key to Ventersdorp chronostratigraphy. However only the proposed 2754-2709 Ma Platberg volcanic province is based on reliably dated Platberg Group volcanic rocks.

show abstract

Section: Sediment Transport By Water or Ice?mentioning

confidence: 96%

Dating detrital zircon from the gold-bearing Ventersdorp Contact Reef in the Ventersdorp Supergroup of South Africa

Cornell

Meintjes

Westhuizen

et al. 2021

Precambrian Research

View full text Add to dashboard Cite

show abstract

“…2.8 Ga Central Slave Cover Group in the Slave Craton (Bleeker et al, 1999); (D) ca. 3.0 Ga West Rand Group of the Witwatersrand Supergroup in the Kaapvaal Craton (Frimmel, 2010).…”

Section: Estimated Secular Change In the Size Of Continentsmentioning

confidence: 99%

Estimation of Secular Change in the Size of Continents for Understanding Early Crustal Development

Sawada

2020

Front. Earth Sci.

View full text Add to dashboard Cite

The size of continents is an essential parameter to understand the growth of the continental crust and the evolution of the solid Earth because it is subject to tectonism and mantle convection and affects the preservation of the crust. This article reviews the secular change in the size of continents on the early Earth, focusing on terrigenous clastic rocks, especially quartzose sandstones occurring on relatively large continents. The earliest continental crust in the Hadean or early Archean was produced with a width of ∼200–500 km, similar to modern oceanic island arcs along subduction zones or oceanic islands in hot spot regions by mantle plume heating. Through the collision and amalgamation of such primitive continental crusts, continental blocks over 500 km in width and length evolved and appeared by ca. 3.5 Ga. Through further amalgamation, during ca. 3.3–2.5 Ga, the Archean continents emerged with widths and lengths greater than 1,000 km, which were still smaller than those of modern continents. Continents with widths and lengths of nearly 10,000 km have existed since ca. 2.4 Ga (early Proterozoic). Further analyses of the composition and formation mechanism of clastic rocks will help reveal more quantitative secular changes in the sizes of continents.

show abstract

“…Moab Khotsong Mine (26.9792°S, 26.7815°E) is a gold and uranium mine located in the Witwatersrand Basin, within the Kaapvaal Craton, South Africa. Geologically, the craton formed approximately 3.7-2.6 Ga and consists of granites-greenstones, tonalite-trondhjemite-granodiorite gneisses, mafic-ultramafic rocks and sedimentary rocks 17,[25][26][27] . The Witwatersrand Basin formed due to tectono-magmatic activity between 3.074 and 2.642 Ga 27,28 .…”

mentioning

confidence: 99%

“…The Witwatersrand Basin formed due to tectono-magmatic activity between 3.074 and 2.642 Ga 27,28 . The Witwatersrand Supergroup is subdivided into the Central Rand Group, consisting primarily of terrigenous quartzites with minor conglomerates and shales, and overlies the West Rand Group, which consists of transitional marine-tocontinental shales and quartzites 26 . Deposition of Witwatersrand Supergroup terminated at 2.714 Ga when the overlying Ventersdorp Supergroup lavas were deposited 28 .…”

mentioning

confidence: 99%

See 1 more Smart Citation

86Kr excess and other noble gases identify a billion-year-old radiogenically-enriched groundwater system

et al. 2022

View full text Add to dashboard Cite

Deep within the Precambrian basement rocks of the Earth, groundwaters can sustain subsurface microbial communities, and are targets of investigation both for geologic storage of carbon and/or nuclear waste, and for new reservoirs of rapidly depleting resources of helium. Noble gas-derived residence times have revealed deep hydrological settings where groundwaters are preserved on millions to billion-year timescales. Here we report groundwaters enriched in the highest concentrations of radiogenic products yet discovered in fluids, with an associated 86Kr excess in the free fluid, and residence times >1 billion years. This brine, from a South African gold mine 3 km below surface, demonstrates that ancient groundwaters preserved in the deep continental crust on billion-year geologic timescales may be more widespread than previously understood. The findings have implications beyond Earth, where on rocky planets such as Mars, subsurface water may persist on long timescales despite surface conditions that no longer provide a habitable zone.

show abstract

The Witwatersrand Basin and Its Gold Deposits

Cited by 32 publications

References 61 publications

Dating detrital zircon from the gold-bearing Ventersdorp Contact Reef in the Ventersdorp Supergroup of South Africa

Dating detrital zircon from the gold-bearing Ventersdorp Contact Reef in the Ventersdorp Supergroup of South Africa

Estimation of Secular Change in the Size of Continents for Understanding Early Crustal Development

86Kr excess and other noble gases identify a billion-year-old radiogenically-enriched groundwater system

Contact Info

Product

Resources

About