The origin of gold in South Africa

The Witwatersrand basin, which covers an area about the size of West Virginia, contains almost as much gold the rest of the Earth's surface combined. There is, of course, enormous interest in the origin of these deposits, and more than a hundred years of mining and scientific research have revealed a complex history for these gold-bearing conglomerates. But the chronology of geologic events is imperfectly understood and the ideas about how all this gold came to be here are quite controversial. Our research group at the University of Arizona has recently taken significant steps toward answering questions about the origin of the Witwatersrand gold. Here we discuss the research and the implications of our results for the geologic history of South Africa.