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 LATEST EARTHQUAKES RECORDED IN THE UK 

Many people think that the UK rarely has Earthquakes, this is simply not the case. In the last 30 days we have seen the following activity.



And if you are not sure what the magnitude or Richter scale means then read on....

The Richter Scale

The Richter magnitude scale was developed in 1935 by Charles F. Richter of the California Institute of Technology as a mathematical device to compare the size of earthquakes. The magnitude of an earthquake is determined from the logarithm of the amplitude of waves recorded by seismographs. Adjustments are included for the variation in the distance between the various seismographs and the epicentre of the earthquakes.

On the Richter Scale, magnitude is expressed in whole numbers and decimal fractions. For example, a magnitude 5.3 might be computed for a moderate earthquake, and a strong earthquake might be rated as magnitude 6.3. Because of the logarithmic basis of the scale, each whole number increase in magnitude represents a tenfold increase in measured amplitude; as an estimate of energy, each whole number step in the magnitude scale corresponds to the release of about 31 times more energy than the amount associated with the preceding whole number value.

To put this into more laymens terms, the various Richter numbers can be thought of as follows

Richter scale no. No. of earthquakes per year Typical effects of this magnitude
< 3.4 800,000 Detected only by seismometers
3.5 - 4.2 30,000 Just about noticeable indoors
4.3 - 4.8 4,800 Most people notice them, windows rattle.
4.9 - 5.4 1,400 Everyone notices them, dishes may break, open doors swing.
5.5 - 6.1 500 Slight damage to buildings, plaster cracks, bricks fall.
6.2  6.9 100 Much damage to buildings: chimneys fall, houses move on foundations.
7.0 - 7.3 15 Serious damage: bridges twist, walls fracture, buildings may collapse.
7.4 - 7.9 4 Great damage, most buildings collapse.
> 8.0 One every 5 to 10 years Total damage, surface waves seen, objects thrown in the air.