Topography of theIndian Ocean shows Mauritius, where researchers discovered a lost continent. Image: (Lewis Ashwal/Journal of Petrology/Oxford University Press
The tiny island of Mauritius is an incredible place. Home of the world famous Tamarin Bay (a wave that Surfing Magazine named one of the “25 Best Waves in the World”), Mauritius sits serenely in the Indian Ocean. Measuring in at just under 800 square miles, it truly is an island paradise, located just to the northeast of Reunion Island. As it turns out, it has held a secret under its dress for a long, long time: it’s been sitting on top an entire lost continent.
Researchers have been studying Mauritius for years because of a very interesting thing. Its gravitational pull is stronger than that of the surrounding areas, which in itself isn’t all that strange. Depending on the density and material of the earth’s crust in any given place, the gravitational pull will vary. Mauritius, though, has a gravitational pull that’s oddly strong. That lead a geologist from South Africa to do something only a geologist would do–on a one-day layover en route to India, Lewis Ashwal and his colleagues decided to go look at rocks. “We’re not the kind of people who are going to waste a day reading a book and getting a sunburn,” Ashwal told the CBC. “Swimming — who cares? I’ve done enough of that.”
After renting a car for the day, the team drove inland, away from the picturesque beaches. They drove to some of the island’s volcanic craters and collected rocks to study. When they did, they found something strange: a mineral called zircon that is normally found in continental granite. The zircon grains were two billion years old. Since Mauritius is relatively young in terms of the age of the earth–about eight million years old–that didn’t make sense. Ashwal returned over the years to collect more samples and was even more confounded. The zircon dated back another billion-or-so years, which lead the team to believe that it had been “blown up onto dry land when undersea volcanoes erupted, blasting out much older rocks from subsurface crust.” That meant, of course, that the rocks beneath Mauritius were part of an ancient super-continent called Gondwanaland, which broke apart into Africa, India, Australia, and Antarctica some 200 million years ago.
The lost continent stretches from India almost to Madagascar. Image: Nature
In a paper just published in Nature Communications, Ashwal and the rest of the researchers concluded that when Gondwanaland began to break apart, a huge chunk of it splintered into long, thin ribbons of land that slowly sank. “The compressed, sunken land created the mass concentrations” Jeffrey Kluger explained on Time. “Subsequent volcanoes created Mauritius, and still later eruptions deposited the telltale zircon.”
The team named the lost continent Mauritia, and while it is lost for forever, all it took was a few grains of a certain mineral and a whole lot of brains to find it.
