Do earthquakes occur in Britain?
YES, between 200 and 300 earthquakes are
detected and located in the UK, by the British Geological Survey annually.
Although distant from the nearest plate boundary, the Mid-Atlantic Ridge,
earthquakes occur as crustal stresses within the tectonic plates are relieved
by movement occurring on pre-existing fault planes. The risk from these
earthquakes is not insignificant and must be considered when engineering
for sensitive installations.
FREQUENCY OF OCCURRENCE OF MAINLAND UK EARTHQUAKES (BASED
ON OBSERVATIONS BETWEEN 1979 AND 1994)
| Magnitude(ML) | Average |
|---|---|
| 5.0 and higher | every 8 yrs |
| 4 - 4.9 | every 2 yrs |
| 3 - 3.9 | 3/yr |
| 2 - 2.9 | 26/yr |
| 1 - 1.9 | 140/yr |
FREQUENCY OF OCCURRENCE OF NORTH SEA EARTHQUAKES (BASED ON OBSERVATIONS BETWEEN 1979 AND 1994)
| Magnitude (ML) | Average |
|---|---|
| 4.0 and higher | 1/yr |
| 3.0 - 3.9 | 4/yr |
| 2.0 - 2.9 | 25/yr |
