Earthquake never far away’
PUBLISHED: 14:18 05 March 2008 | UPDATED: 15:37 16 August 2010
Although statistics tell us it is unlikely, potentially we could have an earthquake on this scale happening anywhere in the UK tomorrow.
Although statistics tell us it is unlikely, potentially we could have an earthquake on this scale happening anywhere in the UK tomorrow."
That is the view of Greg Spellman, an expert on Earth Science, speaking about the earthquake that struck Lincolnshire last Wednesday, the strongest in Britain for 25 years.
The quake, which measured 5.2 on the Richter Scale and occurred 15km below the ground in Market Rasen, was felt right across Britain and people even reported feeling it in parts of south east London and north Kent.
The British Geological Survey recorded a synopsis of European Macroseismic Scale (EMS) which gives an indication of how powerful the tremor was felt across the country.
In north Kent and London it was given a three, which describes a "weak vibration". This indicates a tremor felt by a few people, mostly by people at rest who can feel swaying or light trembling.
London Fire and Rescue service had 16 calls from concerned residents after the tremor hit.
But there were no reported injuries or serious damage in the south east, unlike the most recent earthquake to hit Kent in April last year when parts of Folkestone were damaged and one woman was injured in the tremor which measured 4.3 on the Richter Scale.
Mr Spellman, who lectures at Northampton University, said: "I wouldn't say this earthquake was a particularly bad one, but it was a particularly unusual one.
"We haven't seen an earthquake like this in the UK for the last 25 years, but if you look at it in a global sense, it was merely an earth tremor.
"These can happen anywhere in the UK. What we saw on Wednesday was a bit of a movement of one of the many faults that underline Britain. The earth is full of fractures and cracks and stresses and strains build up on moving earth which results in this movement.
"These faults have been around for millions of years with the UK's Midland Platform, an enormous block of rock which is cut extensively by faults."
Every year in the UK, there are some 200 to 300 quakes in Britain. Most are just so small that no one even notices them.
Kent has experienced two of the biggest earthquakes ever to affect Britain. The first was in 1382 and in 1580 a quake with a magnitude of about six killed two people in London.
Mr Spellman added: "In Kent and south east London there is no specific fault lines, and some people are under the impression that the impact of development and large urban centres has an impact on whether an earthquake will hit, even that global warming may have an affect. It doesn't. You are no more at risk in parts of London than you are anywhere else in the UK. They are powerful natural phenomena.
"You could have an earthquake as big as this occur tomorrow."
The earthquake in Lincolnshire, the strongest recorded since 1984 when a tremor hit Wales is estimated to have caused £10 million worth of damage, according to the Association of British Insurers. There was one report of serious injury, when a student in South Yorkshire narrowly escaped death as a chimney collapsed on him, breaking his pelvis.
Mr Spellman added: "In Britain, you wouldn't normally expect anything as high as 6 on the Richter scale, but the strongest recorded in Britain was recorded in the North Sea in 1931 that measured 6.1 on the Richter scale.
"The largest earthquakes in the world occur close to plate margins, areas of the earth's layers that are being pulled apart or pushed together. A lot of energy is released when these are pulled apart.
"Last week in Indonesia, they recorded a 7 on the Richter Scale. Don't expect anything like that to occur in Britain."
- Earthquakes are caused by the movements of tectonic plates that cover the earth, floating on a sea of liquid rock
- They are in constant motion, and when pressure between the two plates build up, pressure is released causing an earthquake.
- The biggest quakes are on the fault lines between the plates, like the San Andreas Fault in California.
- Britain is in the middle of the Eurasian tectonic plate, which is riddled with smaller weaker fault lines, it was the movement of one of these that caused the Lincolnshire earthquake.
- The nearest major fault line to Britain run down the centre of the Atlantic.
- Earthquakes are measured between one to ten on the Richter scale, developed in 1935 by Charles Richter.