Analysis: On the grand scale, Britain is often shaken but rarely stirred

The UK is not associated with earthquakes. However, between 20 to 30 are felt each year, and hundreds of smaller ones are recorded.

Most are very small and cause no damage. However, some British earthquakes have caused considerable damage, although nothing like that caused by large earthquakes in other parts of the world.

Normally there are two factors which lead to earthquakes. During the glaciation period, ice was heavy on the earth's surface and pushed the ground down. Rebounding is the name now given to the readjustment of the earth's crust. Pressure builds up on the margins of tectonic plates which make up the Earth's surface.

Africa is also being pushed further north, which creates a build-up of pressure. This is then released on a small fault - a weakened point on the plate that is created by crust formation. The UK can only have small quakes as it is far from the edge of a plate.

• Alice Walker is a seismologist at the British Geological Survey in Edinburgh.