An island of Mauritius found traces of the "lost continent"
Scientists have confirmed the existence of the "lost continent" on the island of Mauritius in the Indian Ocean, which was left after the collapse of the supercontinent Gondwana, which began 200 million years ago. Part of the cortex, which was subsequently covered with young lava from the volcanic eruption on the island was a tiny piece of the ancient continent, which was separated from the island of Madagascar, where Africa, India, Australia and Antarctica broke up and formed the Indian Ocean.
"We are studying the process of collapse of the continent, in order to understand the geological history of the planet," says the University of Witwatersrand geologist (Vitsa) Ashval Lewis, the lead author of a paper published in the prestigious journal Nature Communications.
By studying the mineral zircon, found in rocks, an erupting volcano with lava Ashval and his colleagues Michael Uidenbek of the German Research Center for Geosciences (GFZ) and Trond Torsvik of the University of Oslo, a Visiting Scholar at the GFZ, found that the remains this mineral were too old to belong to the island of Mauritius.
"The land consists of two parts - the world who are old, and the oceans are" young ". On the continents, you can find a breed that more than four billion years old, but you will not find anything like it in the ocean, because the new breed, "explains Ashval formed there. "Mauritius - an island, and the island has no rocks older than 9 million years. However, studying the rocks on the island, we found a zircon age of three billion years. "
Zircon - it's the minerals that appear most often in the continental granites. They contain trace amounts of uranium, thorium and lead, as well as going through geological processes, they can also find a rich chronicle of geological processes and highly precise date.
"The fact that we found such a zircon age, shows that under the Mauritius are much older material of the crust, which could be born only on the continent," says Ashval.
On this island is not the first time find zircon age of billions of years. A study conducted in 2013 revealed traces of this mineral in the beach sand. Nevertheless, this study received a lot of criticism, for example, on the fact that this mineral could blow wind or even bring on car tires or scientists shoes.
"The fact that we found ancient zircons in the rock (trachea age 6 million years) reinforces previous research and rejects any suggestion of the possibility to be brought by the wind, waves or something else, as shown by preliminary results," says Ashval.
Ashval suggests that there are many pieces of "undiscovered continent" of various sizes, together referred to as "Maurizio", which are scattered throughout the Indian Ocean and stayed away from Gondwana breakup. The new results show that this decay is not just the splitting of the ancient supercontinent of Gondwana, and the fragmentation of the complex when the continental crust of different sizes have been abandoned to the developing Indian Ocean.
Gondwana supercontinent existed over 200 million years ago and included the rock age 3, 6 billion years before it split into what today is Africa, South America, Antarctica, India and Australia. Chipping occurred due to plate tectonics.