A group of geoscientists from Norway, South Africa, Britain and Germany published a new study in the Feb. 24, 2013, issue of Nature Geoscience that redefines plate tectonics based on new physical evidence and the movement of lava hotspots that indicate ancient continental movement.
The researchers found that the islands Reunion and Mauritius cover a continent fragment that has previously been hidden under huge masses of lava. The continent fragment known as Mauritia detached from Eastern Gondwana about 60 million years ago while Madagascar and India drifted apart.
The volcanic hotspot beneath the islands was previously thought to have been the markings of the trail of the Reunion hotspot because of the lava cover.
Based on the study of lava sand grains from the beach of Mauritius, the researchers predict the existence of more continent fragments ranging in age from 660 and 1,970 million years.
The dating is based on the discovery of zircon fragments in the sands of Mauritius that were formed and ejected during ancient undersea volcanic eruptions. Zircons have been found on Earth as old as four billion years based on the uranium lead (U/Pb) method of radiometric dating.