Ancient continent discovered
A fragment of continental crust has been postulated to underlie the young plume-related lavas of the Indian Ocean island of Mauritius based on the recovery of Proterozoic zircons from basaltic beach sands. Scientists identified concordant Archaean xenocrystic zircons ranging in age between 2.5 and 3.0 billion years within a trachyte plug that crosscuts Older Series plume-related basalts of Mauritius. The study demonstrates the existence of ancient continental crust beneath Mauritius (which is supposed to be only 8 million years old); based on the entire spectrum of U–Pb ages for old Mauritian zircons, scientists demonstrate that this ancient crust is of central-east Madagascar affinity, which is presently located ∼700 km west of Mauritius. This makes possible a detailed reconstruction of Mauritius and other Mauritian continental fragments, which once formed part of the ancient nucleus of Madagascar and southern India.
