Scientists discovered ‘misplaced continent’ underneath Mauritius

The Seven Coloured Earths of Mauritius. Credit: MNStudio/Shutterstock.com

Earth nonetheless has some large secrets and techniques.

Newly found crystals expelled from volcanic eruptions on the island of Mauritius are billions of years older than the island itself, and are considered the remnants of an historic microcontinent often known as Mauritia.

The proposed ‘misplaced continent’ would have as soon as related Madagascar and India within the Gondwana supercontinent, however doubtless disappeared into the Indian Ocean round eighty four million years in the past. Now researchers have discovered what seems to be a bit of Mauritia, dredged up by historic volcanoes and hidden under the floor.

“Earth is made up of two elements – continents, that are previous, and oceans, that are ‘younger’,” says one of many group, Lewis Ashwal from the University of the Witwatersrand in South Africa.

“Mauritius is an island, and there’s no rock older than N million years previous on the island. However, by learning the rocks on the island, we’ve discovered zircons which might be as previous as A billion years.”

The island of Mauritius is situated about P,000 kilometres (M,200 miles) off the southeast coast of the African continent.

Thought to be a comparatively new landmass, the island was shaped by gigantic underwater volcanic eruptions between H and N million years in the past, and now belongs to the Mascarene Islands archipelago, together with the Saint Brandon, Réunion, and Rodrigues islands.

Ashwal and his workforce dug up the piece of crust from a rocky outcrop in Mauritius that had been coated by molten lava throughout volcanic eruptions on the time of the island’s formation.

When they analysed the fabric inside, they discovered tiny zircon crystals that have been billions of years older than the landmass itself.

The proven fact that the crystals have been created from zircon – a standard gemstone that may are available colourless, yellow, purple, brown, blue, and inexperienced hues – was sufficient to tip off the researchers that what they have been taking a look at didn’t come from the ocean under.

Zircons are recognized to type primarily from the granites of historic continents that when unfold throughout Earth’s floor, and as soon as the group dated the crystals to between P.H and A billion years, they are saying it is a robust indication that they belonged to the lengthy-misplaced continent of Mauritia.

“The proven fact that we now have discovered zircons of this age proves that there are a lot older crustal supplies beneath Mauritius that would solely have originated from a continent,” says Ashwal.

This isn’t the primary time that historic zircons have been discovered on the island of Mauritius – again in 2013, a separate workforce discovered traces of zircon in seashore sand that have been additionally billions of years previous.

But the discover was controversial, as a result of critics argued that these minerals might have blown onto the seashore from elsewhere.

Now that we’ve got comparable crystals that have been buried by historic lava deposits, scientists could make a a lot stronger case for them being the stays of a misplaced continent.

“The undeniable fact that we discovered the traditional zircons in rock corroborates the earlier research, and refutes any suggestion of wind-blown, wave-transported, or pumice-rafted zircons for explaining the sooner outcomes,” says Ashwal.

The discover now paints an image of an historic continent being splintered into fragments, a few of which ended up being anchored under the present landmass that makes up the island of Mauritius as we speak.

It additionally explains the thriller of why some elements of the Indian Ocean have been discovered to have stronger gravitational fields than others – a possible indication of thicker crusts.

It’s anticipated that extra chunks of the traditional Gondwana supercontinent will probably be dredged up within the coming years.

As Alice Klein studies for New Scientist, a number of items of continent have just lately been discovered off the coast of Western Australia and beneath Iceland.

“It’s solely now as we discover extra of the deep oceans that we’re discovering all these bits of historic continents across the place,” Martin Van Kranendonk from University of New South Wales in Australia, who wasn’t concerned within the research, informed Klein.

The above submit is reprinted from materials offered by Wits University.