Fragments of continental crust have cyclically assembled to form supercontinents throughout geological time. Most of the continental landmasses on Earth contain very old (3.8 to 2.5 billion year old) and geologically stable interiors, called cratons. The oldest supercontinent, Kenorland, is believed to have been in existence about 2.7 billion years ago. The cratons were the puzzle pieces that made-up Kenorland.
Today the pieces have been partially destroyed, deformed and randomized by plate tectonic processes making it very difficult to reconstruct the ancient landmass. A shared geological history between the old interior of South Africa (Kaapvaal craton) and that of Northwest Australia (Pilbara craton) suggests that these were neighbors within Kenorland in an arrangement known as “Vaalbara”.
New age dating on rock units from South Africa together
with the ancient record of the Earth’s magnetic field allows us to follow the Vaalbara existence between 2.78 and 2.45 billion years ago, and to speculate upon its formation and breakup in a time interval when large world-class economic deposits were formed in South Africa
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