NPR : News

Filed Under:

Scientists May Have Uncovered Ancient Microcontinent

The remains of a small continent have been hiding right under our noses for the past 85 million years or so.

That's according to a new study published Sunday in the journal Nature Geoscience. Scientists looked at lava sands from beaches on Mauritius to determine when and where the material might have originated.

Their conclusion? The lava sands, containing particles called zircon xenocrysts, came from a Precambrian microcontinent dubbed "Mauritia" that was sandwiched between the land masses that today make up Madagascar and India. It was all part of a supercontinent known as Rodinia that existed between 2 billion and 85 million years ago. (Not to be confused with the better known and slightly more contemporary supercontinent Pangaea).

Mauritia was a sliver of land that broke apart and disappeared under the sea as the Rodinia ripped itself apart as part of the process of plate tectonics, scientists believe.

The BBC quotes the study's lead author, Trond Torsvik, as saying the sand his team examined dates to a 9-million-year-old eruption near the modern-day islands of Marion and Reunion that spewed much older material.

"We found zircons that we extracted from the beach sands, and these are something you typically find in a continental crust. They are very old in age," said Torsvik of the University of Oslo in Norway.

Torsvik believes pieces of Mauritia have been interred under 6 miles of surface and spread over a swath of the Indian Ocean, according to the BBC.

"However, a small part could have survived.

" 'At the moment the Seychelles is a piece of granite, or continental crust, which is sitting practically in the middle of the Indian Ocean,' explained Prof Torsvik.

" 'But once upon a time, it was sitting north of Madagascar. And what we are saying is that maybe this was much bigger, and there are many of these continental fragments that are spread around in the ocean.' "

Copyright 2013 NPR. To see more, visit http://www.npr.org/.

NPR

'Theeb' Looks At Middle East History Through The Eyes Of A Bedouin Boy

The Oscar-nominated film is set in 1916 Saudi Arabia, a pivotal time in the region. Director Naji Abu Nowar says he wanted to explore "how strange and surreal it must have been" for the Bedouins.
NPR

Beer And Snack Pairings: A Super Bowl Game Everyone Can Win

Which beer goes with guacamole? How can a brew complement spicy wings? Two craft beer experts share their favorite pairings and help us take our Super Bowl snack game to the next level.
NPR

Tourists Flock To New Hampshire For Front Row Seat To Presidential Politics

NPR's Robert Siegel reports on people who are not involved in presidential campaigns traveling to New Hampshire to observe the action surrounding the primary. There are families trying to give their kids a civics lesson, couples trying to see presidential politics up close, and groups of students who serve as interns for campaigns as part of their studies.
NPR

OK, Google, Where Did I Put My Thinking Cap?

It can be too easy for students to Google an assignment before they stop to think about it. Some researchers say we're losing our critical thinking and memory skills by relying on the search bar.

Leave a Comment

Help keep the conversation civil. Please refer to our Terms of Use and Code of Conduct before posting your comments.