Ancient continent hides beneath Indian Ocean

[The Lawspeaker]

Ancient continent hides beneath Indian Ocean


Sand as old as the dinosaurs (Image: Michael Friedel/Rex Features)

The sands of Mauritius are hiding a secret: deep beneath them lurks an ancient continent.

Trond Torsvik and colleagues at the University of Oslo, Norway, analysed grains of zircon found on the island's beaches, measuring the balance of lead and uranium isotopes to work out their age. This showed some formed almost 2 billion years ago – although the volcanic island is no more than 65 million years old.

So where did the grains come from? Torsvik thinks they are from fragments of continental crust beneath Mauritius that melted as the volcanic island formed. The team have named the proposed continent Mauritia.

It's a reasonable idea, says Michael Wysession at Washington University in St. Louis, Missouri. "It's hard to imagine how zircons could be there any other way."

Journal reference: Nature Geoscience, DOI: 10.1038/ngeo1736

(Source: New Scientist, 24 February 2013)

[Svipdag]

To a geologist, this is exciting news. preCambrian continental crust is rare because, in the billion or more of years since, most of it has been eroded away and incorporated into oceanic sediments or buried under later deposits. Mauritia, if confirmed, is another piece in the 4-dimensional jigsaw puzzle of the earth's crust.

[The Lawspeaker]

To a geologist, this is exciting news. preCambrian continental crust is rare because, in the billion or more of years since, most of it has been eroded away and incorporated into oceanic sediments or buried under under later deposits. Mauritia, if confirmed, is another piece in the 4-dimensional jigsaw puzzle of the earth's crust.

This must be fantastic news for you. Do you think there is actually an ancient continent there ?

[Hurrem sultana]

cool

[The Lawspeaker]

O.K.. that's it. We are going to send in some dike builders, windmills and people that dig canals and know how to operate the equipment. We are going to make ourselves some tropical Lebensraum.