The catastrophic earthquake which hit Chile today was caused by the Pacific ocean floor gradually sliding under the continent of South America.
The 8.8 magnitude quake, which struck at 6:34am GMT about 115km (70 miles) north-east of the city of Concepcion and 325km south-west of the capital, Santiago, has killed scores of people.
A tsunami warning has been raised across 53 countries from South America to Australia and the US state of Hawaii.
Chile lies in an earthquake hotspot surrounding the Pacific known as the "ring of fire".
About 90 per cent of the world’s earthquakes take place in the volatile 40,000km arc, which stretches from New Zealand, along the eastern edge of Asia, north across the Aleutian Islands of Alaska, and south along the coast of North and South America.
The extreme seismic and volcanic activity is a result of movements and collisions between the tectonic plates above and below the ocean.
This morning’s quake occured on the border between the South American Plate, which is moving west, and the submerged Nazca Plate, which is very gradually sliding under it.
However, while seismic tremors and earthquakes in the region are common, geologists say ones of today’s magnitude are rare.
Dr Brian Baptie of the British Geological Survey said: “In global terms this is a very rare quake.
"Chile has experienced some very big quakes in the past. It was about 124 miles north east of the largest earthquake ever recorded - 9.5 - in 1960, which resulted in a destructive tsunami that killed many thousands of people around the Pacific.”
The epicentre of today’s quake was located under the sea floor and created a sudden displacement of huge quantities of water which radiated outwards in a wave.
Dr Baptie said: “Tsunami waves in the deep ocean travel about the same speed as a jet plane and would take about 15 hours to reach Hawaii and about 20 hours to reach the other side of the Pacific.”
Chile also faces the prospect of more aftershocks, according to Dr Baptie. “There have been many aftershocks from this event so far of magnitude 6 and higher. The bigger the quake, the bigger the aftershocks.
“They will decrease with time after the main shock but they could carry on for some time.”
The devastating tsunami which hit Asia in 2004 measured 9.3 on the Richter scale and was the second largest ever recorded after the 1960 Chile quake.
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this is sad. I'm speechless rite now. I hope the situation will get better.
