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IN ASSOCIATION WITH
PLANET EARTH
The Nile is much younger
than we thought
Words by Yasemin Saplakoglu
F
or thousands of years the Nile River has
fertilised valleys along its w inding path
through northeastern Africa, anchoring
ancient civ ilisations and still ser v ing as a route
of transport and irrigation today.
But the age of its venerable waters, which
stretch over 6,800 kilometres, has been debated,
w ith one group of experts claiming the river was
born around six million years ago when a
drainage system changed course, while another
claims the river is five times older than that.
A recent study finds ev idence that supports
the latter theor y: the Nile River may have
emerged around 30 million years ago, driven by
the motion of Earth’s mantle – the thick layer of
rock bet ween the Earth’s core and crust.
The Nile River begins
high up in the Ethiopian
Highlands near the Blue
Nile Falls shown here
The Nile River is thought to have formed at the
same time as the Ethiopian Highlands, said lead
author Claudio Faccenna, a professor at the
Jackson School of Geosciences, University of
Texas. The Ethiopian Highlands is where one of
the Nile River’s major tributaries, or branches,
called the Blue Nile, begins.
The Blue Nile brings in the majority of the Nile
River’s water – and most of the sediments in it
- joining with the river’s other tributar y, the
White Nile, in Sudan before empt y ing out into
the Mediterranean Sea.
Faccenna and his team had prev iously
analysed sediments collected from the Nile
Delta – land created as sediment is deposited
where the river meets the Mediterranean –
and compared their composition and age
with ancient volcanic rock found on the
Ethiopian plateau. They found that the
sediments and rocks matched and were
between 20 million and 30 million years old,
suggesting the river formed at the same time
as the plateau.
“The Nile River may
have emerged around
30 million years ago,
driven by the motion of
Earth’s mantle”
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