A major Archean, gold- and crust-forming event in the Kaapvaal craton, South Africa.

@article{Kirk2002AMA,
  title={A major Archean, gold- and crust-forming event in the Kaapvaal craton, South Africa.},
  author={Jason Dale Kirk and Joaqu{\'i}n Ru{\'i}z and John T. Chesley and John L Walshe and Gavin L. England},
  journal={Science},
  year={2002},
  volume={297 5588},
  pages={1856-8}
}
The 2.89- to 2.76-gigayear-old conglomerates of the Central Rand Group of South Africa host an immense concentration of gold. The gold and rounded pyrites from the conglomerates yield a rhenium-osmium isochron age of 3.03 +/- 0.02 gigayears and an initial 187Os/188Os ratio of 0.1079 +/- 0.0001. This age is older than that of the conglomerates. Thus, the gold is detrital and was not deposited by later hydrothermal fluids. This Middle Archean gold mineralization event corresponds to a period of… CONTINUE READING