Evidence of a Brazlian Atlantis?

A lost continent off the coast of Brazil may have been found, scientists announced this week.

Granite boulders dredged from the seafloor off the coast of South America two years ago could be remnants of a long-vanished continent, according to Roberto Ventura Santos, the geology director of Brazil's Geology Service.

"This could be the Brazilian Atlantis," Santos told reporters, adding that he was speaking metaphorically and not claiming to have found the legendary sunken world. "Obviously, we don't expect to find a lost city in the middle of the Atlantic," he said.

Santos and his team speculated that the granite—a relatively low-density rock found in continental crust—belonged to a continent that was submerged when Africa and South America drifted apart and formed the Atlantic Ocean about 100 million years ago.

But Michael Wysession, an Earth and planetary scientist at Washington University in St. Louis, noted that granite can find its way onto the seafloor through other means. "There are pieces of granite in the middle of the seafloor that date to about 800 million years ago when we had a snowball Earth scenario and there were large pieces of rock embedded in ice rafts"—mobile glaciers, essentially—"all over the ocean," explained Wysession, who was not part of the discovery. "As those ice rafts were melting, large blocks of rock dropped down all over the seafloor.

Wysession thinks that because the ocean floor has been extensively mapped with satellites, it is unlikely that evidence for any major lost continent will be found. "There's nothing that big that's hidden down there," he said.