a day ago
Africa is tearing in HALF: Scientists detect deep Earth pulses beneath Ethiopia - in ominous sign that the entire continent could rupture
We know that all of the world's continents are constantly moving.
But one of them has already begun a dramatic transformation.
Scientists say a massive crack has started ripping through Africa, from the north east to the south.
The experts uncovered evidence of rhythmic surges of molten rock rising from deep within the Earth's surface, beneath Ethiopia.
These pulses are gradually tearing the continent apart and forming a new ocean – although it's happening so slowly it's basically imperceptible.
'The split will eventually go all the way down Africa,' lead author Dr Emma Watts, a geochemist at Swansea University, told MailOnline.
'It has already begun and is happening now but at a slow rate – 5-16 mm per year – in the north of the rift.
'Regarding timescales, this process of Africa being torn apart will take several million years before it is completed.'
Dr Watts and colleagues point to the Gulf of Aden, a relatively narrow body of water separating Africa in the south and Yemen in the north.
Like a small tear in a piece of clothing, the gradual separation event could start at the Gulf of Aden and gradually spread downwards.
As it does so, it would split through the middle of enormous bodies of water in East Africa, such as Lake Malawi and Lake Turkana.
By the time the split is complete, several million years from now, Africa would be made up of two landmasses.
There would be the larger landmass in the west featuring most of the 54 modern-day African countries, such as Egypt, Algeria, Nigeria, Ghana and Nambia.
Meanwhile, the smaller landmass to the east will include Somalia, Kenya, Tanzania, Mozambique and a large portion of Ethiopia.
'The smaller part that breaks away towards the east will be approximately 1 million square miles in area,' Dr Watts told MailOnline.
'And the remaining larger landmass will be just over 10 million square miles.'
The layers of Earth
Crust: To a depth of up to 43 miles (70km), this is the outermost layer of the Earth, covering both ocean and land areas.
Mantle: Going down to 1,795 miles (2,890km) with the lower mantle, this is the planet's thickest layer and made of silicate rocks richer in iron and magnesium than the crust overhead.
Outer core: Running to a depth of 3,200 miles (5,150km), this region is made of liquid iron and nickel with trace lighter elements.
Inner core: Going down to a depth of 3,958 miles (6,370km) at the very centre of Earth, this region is thought to be made of solid iron and nickel.
For the study, the team collected more than 130 volcanic rock samples from across the Afar region.
In this region, three tectonic plates converge (the Main Ethiopian Rift, the Red Sea Rift and the Gulf of Aden Rift), making it a hotbed of volcanic activity.
The experts used these samples, plus existing data and advanced statistical modelling, to investigate the structure of the Earth's crust and the mantle below it.
The mantle, the planet's thickest layer, is predominantly a solid rock but behaves like a viscous fluid.
'We found that the mantle beneath Afar is not uniform or stationary – it pulses,' said Dr Watts.
'These ascending pulses of partially molten mantle are channelled by the rifting plates above.'
Over millions of years, as tectonic plates are pulled apart at rift zones like Afar, they stretch and thin – almost like soft plasticine – until they rupture, marking the birth of a new ocean.
Geologists have long suspected that a hot upwelling of mantle, but until now, little was known about the structure of this upwelling, or how it behaves beneath rifting plates.
The team say the pulses appear to behave differently depending on the thickness of the plate, and how fast it's pulling apart.
The findings, published in Nature Geoscience, show that the mantle plume beneath the Afar region is not static, but dynamic and responsive to the tectonic plate above it.
'We have found that the evolution of deep mantle upwellings is intimately tied to the motion of the plates above,' said co-author Dr Derek Keir, associate professor in earth science at the University of Southampton and the University of Florence.
'This has profound implications for how we interpret surface volcanism, earthquake activity, and the process of continental breakup.
'The work shows that deep mantle upwellings can flow beneath the base of tectonic plates and help to focus volcanic activity to where the tectonic plate is thinnest.
'Follow on research includes understanding how and at what rate mantle flow occurs beneath plates.'
The Earth is moving under our feet: Tectonic plates move through the mantle and produce Earthquakes as they scrape against each other
Tectonic plates are composed of Earth's crust and the uppermost portion of the mantle.
Below is the asthenosphere: the warm, viscous conveyor belt of rock on which tectonic plates ride.
Earthquakes typically occur at the boundaries of tectonic plates, where one plate dips below another, thrusts another upward, or where plate edges scrape alongside each other.
Earthquakes rarely occur in the middle of plates, but they can happen when ancient faults or rifts far below the surface reactivate.
