Scientists find an EXTRA

layer of plate tectonics within

Earth's mantle that could be

causing strange tremors

across the Pacific

Researchers used 3D mapping to create a picture of the
Earth's inner layers
The map shows a Pacific slab deep in the Earth's layer of mantle
Scientists believe breaks in this slab could be causing
the earthquakes
The map could also give an idea of Earth's surface layout
millions of years ago

The findings suggest that this plate movement could explain the

Vityaz earthquakes – a series of deep and powerful earthquakes that

have been appearing between Fiji and Australia. Pictured is the eruption

of a volcano caused by one of these earthquakes in Tonga

For decades, a mysterious series of earthquakes has rocked the Pacific,

although the source has remained a mystery.

Now, researchers believe they may have found a new layer of

tectonic plates within the Earth's mantle that could explain the

quakes.

While the results are preliminary, if they are verified, they could help

scientists to reconstruct the layout of the Earth's surface millions of years

ago.

Using 3D mapping, the team has been able to generate a picture of

Earth's interior, based on vibrations from earthquakes. Pictured in

purple and white is the subducted Pacific slab, and pictured in red

are the sites of the earthquakes

THE NEW

LAYER OF

PLATE

TECTONICS

Researchers from the

University of Houston have

presented early evidence

of plate tectonics within

the mantle.

The team suggests that

plates that were driven into

the mantle millions of years

ago may slide horizontally

inside the 'transition zone' –

a layer of mantle that lies

440-660km below the surface.

Using 3D mapping, the team

has been able to generate

a picture of Earth's interior,

based on vibrations from

earthquakes.

The findings suggest that this

plate movement could explain

the Vityaz earthquakes –

a series

of deep and powerful

earthquakes

that have been appearing

between

Fiji and Australia.

The researchers believe

that

the bends and breaks in

these

subducted plates could be

generating

the earthquakes.

And as tectonic plates meet, the oceanic plates are driven down into the mantle, in a process known as subduction.

According to The Guardian, researchers from the University of Houston have presented early evidence of plate tectonics within the mantle.

The mantle is the mostly-solid bulk of Earth's interior. It lies between Earth's core and its thin outer layer, the crust.

Presenting their findings at the Japan Geoscience Union and the American Geophysical Union in Tokyo, the researchers suggest that plates that were driven into the mantle millions of years ago may slide horizontally inside the 'transition zone' – a layer of mantle that lies 440-660km below the surface.

Using 3D mapping, the team has been able to generate a picture of Earth's interior, based on vibrations from earthquakes.

The findings suggest that this plate movement could explain the Vityaz earthquakes – a series of deep and powerful earthquakes that have been appearing between Fiji and Australia.

The researchers believe that the bends and breaks in these subducted plates could be generating the earthquakes.

Dr Jonny Wu, lead author of the study, told The Guardian: 'Basically, 90 per cent of Earth's deep seismicity (more than 500km deep) occurs at the Tonga area where we've found our long, flat slab.'

The researchers hope that their pictures of the inner Earth could be used to find other subducted tectonic plates in the mantle and then to reconstruct the layout of plates on Earth's surface millions of years ago.

The findings suggest that this plate movement could explain the Vityaz

earthquakes – a series of deep and powerful earthquakes that have been

appearing between Fiji and Australia. Pictured is the eruption of a volcano

caused by one of these earthquakes in Tonga

For example, the team recently discovered an 8,000 kilometre-wide

stretch

of ocean, which they have named the East Asian Sea, that existed 52

million

years ago, but is now buried deep within the mantle.

Dr Wu said: 'We're discovering lost oceans that we didn't even know

existed.'

While most subducted plates will sink past the mantle's transition zone,

under the western Pacific, the slabs come to a halt, according to the

researchers.

The researchers believe that the bends and breaks in these subducted

plates could be generating the earthquakes. Pictured is ash rising from

an undersea volcanic eruption caused by one of the deep sea earthquakes

in Tonga

Dr Wu said: 'The Pacific subduction rate is so fast that you've got to find

space to get all the slab in there, and east Asia has had such a long history

of subduction it's jammed up.

'So this slab is forced to slide within the upper mantle and transition

zone and be thrust under China.'

The findings are preliminary and are yet to be peer reviewed.

(The Mail, UK)

BeulalandBlog

Wednesday, 24 May 2017