An earthquake centred off the coast of Turkey could be felt in Fethiye yesterday morning.

According to the Kandilli Observatory and Earthquake Research Institute the quake measured 4.7 on the Richter Scale and the epicentre deep under the sea between the Turkish peninsula of Datca and the Greek island of Kos.

The quake could be felt in Fethiye to those sitting around, but for many people going about their daily business the effects were too small to notice.

Later in the afternoon the local Cameli fault lines in the mountains beyond Nif/Arpacik decided to tremble too with a 2.8 quake.

Many parts of Greece and Turkey, including Fethiye, are situated on or near major fault lines or cracks in the earths crust that move from time to time.

Fethiye was levelled in 1957 by an earthquake measuring 7.2 on the Richter scale. The nearby Greek island of Rhodes was also significantly damaged.

What is the Richter Scale?

The Richter Scale is the best known scale for measuring the magnitude of earthquakes. The magnitude value is proportional to the logarithm of the amplitude of the strongest wave during an earthquake. A recording of 7, for example, indicates a disturbance with ground motion 10 times as large as a recording of 6. The energy released by an earthquake increases by a factor of 30 for every unit increase in the Richter scale.

So what does that mean to the person on the street?

The table below describes what happens at different magnitudes:

<3.4 Mostly undetectable by humans
3.5 – 4.2 Noticeable indoors
4.3 – 4.8 Windows and doors rattle
4.9 – 5.4 Every one notices, lights swing and things may shake off shelves
5.5 – 6.1 Slight damage to buildings, plaster cracks, loose masonry will fall
6.2 – 6.9 Damage to buildings, foundations move and chimneys will fall
7.0 – 7.3 Serious damage – buildings may collapse
7.4 – 7.9 Major damage to roads, rail and all buildings
Over 8 Total damage, the ground will be seen to move

The above effects may be different depending on the structure of the ground. Those on unstable ground such as clay will feel greater effects than those on a stable ground such as granite.