[26
SEP 00]
WARWICKSHIRE COUNTY COUNCIL NEWS
Warwick Tremor -
An Expert Explains
The tremor that
shocked Warwick and parts of the Midlands may have been the most
powerful in the UK for a decade, but was little more than a blip when
compared with worldwide quakes.
The shake was centred
below Budbrooke, just west of the town when it struck about 5.30am on
Saturday. It measured four on the Richter Scale.
Aftershocks were felt
as far away as Solihull, Banbury, Peterborough, Leicestershire and
across Warwickshire.
And while it was as
nothing compared to pictures we seen on TV screens from around the
world, an expert explains that quakes in Britain are far more common
than you might think.
Jon Radley, keeper of
geology for Warwickshire Museum, explained:
“The
Warwick Earthquake of September 23 is the latest of many mild tremors to
have affected central England during its long geological history.
“Geological
maps and records held at Warwickshire Museum show that the area is criss-crossed
with geological faults – fractures running through the rocks.
“Many of
these indicate earlier earthquakes and disturbances, some dating back
hundreds of millions of years. Landslides on steep hillsides, or even
mining subsidence may have caused some of the most recent ones.
“We know
that this particular ‘quake originated 13 kilometres down in the
Earth’s crust, just to the west of Warwick. Here, a tiny amount of
movement on an ancient fault caused shock waves to spread upwards and
outwards through the rock layers causing the tremor.”
And the
Warwick incident was caused by actions far from British, even European
shores.
Mr Radley
put it into a global perspective and explained what there is no need to
panic. He said:
“Many
British earthquakes result from pressures building up in the Earth’s
crust, due to the process known as continental drift.
“As the
African continent continues to shunt slowly northwards and the Atlantic
Ocean continues to widen, Britain is effectively a ‘piggy in the
middle’.
“Something
has to give from time to time, and occasionally a small slip will occur
along one of the many ancient faults, the main lines of weakness. It is
worth remembering that these processes are taking place at an incredibly
slow rate, perhaps just a few millimetres each year.
“Central
England is well known in geological circles for it’s tranquil past so
we have nothing to fear! Real earthquake zones such as parts of
California sit astride huge active faults, moving at the rate of several
centimetres a year.
“Old
press cuttings and other documents preserved within Warwickshire
Museum’s Geological Localities Record Centre confirm that local
earthquakes are few and far between, so we can all rest assured of a
quiet future.”
SEE:
[23 SEP 00] EARTHQUAKE IN BUDBROOKE
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