A group of researchers headed by Wits University geologist Professor Lewis Ashwal have revealed that a lost continent is buried under the island of Mauritius.
Their new study, which focused on the break-up process of the continents to understand the planet’s geological history, was published in the prestigious journal, Nature Communications.
Lewis Ashwal, who is lead author of the paper, stated that the lost continent was actually a left over from the break-up process of the super-continent.
This break-up started about 200 million years ago and split up the super-continent ‘Gondwanaland’, which contained rocks as old as 3.6 billion years old, into what is now Africa, South America, Antarctica, Australia and India.
“The piece of crust under Mauritius, which was subsequently covered by young lava during volcanic eruptions on the island, seems to be a tiny piece of ancient continent, which broke off from the island of Madagascar when Africa, India, Australia and Antarctica split up and formed the Indian Ocean,” Professor Ashwal said.
While studying zircon, which is found in rocks formed from lava emitted during volcanic eruptions, the researchers consisting of Ashwal and his two colleagues from the German Research Center for Geosciences (GFZ) and the University of Oslo found that remnants of the mineral zircon were far too old to belong to Mauritius.
“Mauritius is an island, and there is no rock older than 9 million years old on the island. However, by studying the rocks on the island, we found zircons that are as old as 3 billion years,” Ashwal stated.
The geologists concluded that the zircons of this age which had been discovered confirmed that there are much older crustal materials under Mauritius which originate from a continent.
A 2013 study previously found traces of billions of years old zircons in the beach sand in Mauritius, however the study was largely criticized by other scientists who suggested that the mineral could have been blown in by wind or carried in on vehicle tyres or shoes.
“The fact that we found the ancient zircons in rock corroborates the previous study and refutes any suggestion of wind-blown, wave-transported or pumice-rafted zircons for explaining the earlier results,” lead researcher Ashwal underlined.
The volcanic island of Mauritius is mostly known as a tropical holiday destination and was formed by the eruption of volcanoes starting about 9 million years ago.