Floors and walls shake as quake hits Britain, By David Derbyshire, Science Correspondent
PARTS of Britain were shaken, if not stirred, yesterday as an earthquake shook windows, rattled crockery and woke up dozens of bemused sleepers.
Homes across Devon and Cornwall were rocked by the quake, which measured 3.6 on the Richter scale. Although the tremors caused no major damage, they were described by seismologists as "quite significant".
Yesterday, the epicentre was pinpointed to a previously unknown weakness in the Earth's crust 16 miles under the seabed of the Bristol Channel, six miles west of Hartland Point, Devon. The tremors, which started at 12.45am and lasted several seconds, were picked up by seismic monitoring stations as far away as Scotland.
More than 40 people contacted Devon and Cornwall Police to complain of rumbles, shakes and rattles. There were no reports of injuries, but some buildings had minor damage.
Shaun Mather, who lives in a 150-year-old miner's cottage at Callington, Cornwall, said: "My first impression was it was a nuclear bomb. For a strange reason, I don't know why, that is what I thought."
Rachel Parsley, his girlfriend, said she thought she was going to die. "It started to get louder and louder. The room shook. I actually felt the beams were moving, you could hear the roof moving, and it then passed on through. I was really scared. I have never experienced anything like it."
Howard Norman also felt the tremor in the centre of Boscastle in north Cornwall. "We thought it was a sonic boom to start with. The walls and the windows of the bedroom were vibrating and it just carried on. When you get a sonic boom it passes within a few seconds but this lasted about 25 to 30 seconds. It was very alarming. The walls were shaking, the floor was shaking, the ceiling was shaking and we really wondered what was going on."
British earthquakes are usually triggered by the drifting apart of the American and European tectonic plates, or, more rarely, the collision of the African plate into Europe. Scotland, Wales and the West of England are most vulnerable, although quakes can occur on faults that riddle the British Isles.
Alice Walker, the head of seismic monitoring at the British Geological Survey, said the Cornwall tremor was the 13th to shake Britain this month. "On average 30 earthquakes are felt by people each year, although last year there were 17. On average we get 200 earthquakes annually. Britain is an area of low seismic activity, although we get the odd one that can cause damage."
Every 10 years, an earthquake larger than magnitude five hits Britain. The last was in 1990, when a 5.1 magnitude tremor shook Bishop's Castle in Shropshire. A 5.4 quake in Lleyn, north Wales, in 1984, was big enough to topple chimney pots in Liverpool 100 miles away.
Tremors are detected by the British Geological Survey's 146 seismograph
stations. They can detect quakes at the other side of the world, or the
footsteps of a dog a few feet away.
-- Anonymous, June 02, 2001