*NEWS*SECRETS OF OCEAN BIRTH LAID BARE

[Anonymous]

Secrets of ocean birth laid bare
The
largest tear in the Earth’s crust seen in decades, if not centuries,
could carve out a new ocean in Africa, according to satellite data.
Geologists
say a crack that opened up last year may eventually reach the Red Sea,
isolating much of Ethiopia and Eritrea from the rest of Africa.The
60km-long rift was initially sparked by an earthquake in
September.Follow-up observations reported in the journal Nature suggest
the split is growing at an unprecedented rate.

We think if these processes continue, a new ocean will eventually form Dr Tim Wright, University of Oxford

It
betrays events deep beneath the ground, where some of the tectonic
plates that form Africa are gradually moving apart from the Arabian
plate, causing the crust to stretch and thin.As rifts appear, molten
rock bubbles up from beneath the surface, hardening to form a new strip
of ocean floor.Dr Tim Wright from the University of Oxford, UK, said if
the ripping of the crust continued, the horn of Africa would eventually
split off from the rest of the continent, in about a million years.”We
think if these processes continue, a new ocean will eventually form,”
he told the BBC News website. “It will connect to the Red Sea and the
ocean will flow in.”

Fundamental processes
Dr Wright is a
member of a team from the UK and Ethiopia that has been monitoring the
creation of the new ocean basin; a rare event on dry land.They used
sensitive seismic instruments, field measurements and satellite images
from the European Space Agency’s Envisat spacecraft to study what is
happening beneath the ground.”We’ve been able to work up all the
satellite data and get a very precise map,” said Dr Wright.”It’s the
biggest rifting episode at least since the 1970s and possibly in
hundreds of years.”It’s the first time we’ve been able to use satellite
images to investigate the fundamental processes behind rifting.”The
shift in the Earth’s plates has been happening gradually over the
course of two million years but every now and again earthquakes and
volcanic eruptions herald sudden break-ups.

Space techniques
One
such event took place in September last year, opening up a 60km-long
(37 mile) stretch of a fault-line that runs from Ethiopia to the
southern edge of the Red Sea.”It’s amazing,” said Cindy Ebinger, from
Royal Holloway, University of London.”It’s the first large event we
have seen like this in a rift zone since the advent of some of the
space-based techniques we’re now using.”These techniques give us a
resolution and a detail to see what’s really going on and how the Earth
processes work.”Scientists have calculated that 2.5 cubic km (0.6 cubic
mile) of magma has flowed up through the crack in the Earth’s crust.It
is enough to fill London’s Wembley stadium 2,000 times or smother the
area within the capital’s M25 orbital motorway with molten rock to a
depth of 1m (1 yard).

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July 25, 2006 at 10:53 AM