Active planet: Asia-Pacific rocks as earthquakes rumble around region

I had just checked into a hotel in Singapore and was working when the building began to sway. Gradually, people around me began to work out what was happening, but no one said anything until someone else came in and said "I feel strange, a bit like sea sick." He had been sleeping and the motion had woken him.

But the earthquake one of many that has afflicted Pacific Rim and Indian Ocean countries in the past week, was no where near Singapore: it was in West Sumatra, more than six hundred kilometres away. At 6.4, it was severe. More than twice as severe as the 5.1 shock of just 16 hours earlier in the same general area. A rise from 5 to 6 means a doubling of intensity on the Richter Scale.

Last Tuesday, flights into and out of Tokyo airport were disrupted for as much as 8 hours as the runway was checked for damage after a massive 'quake took out highways, railways and demolished buildings. It was one of a three separate events, not including aftershocks, that afflicted Japan in a matter of a few days. The country is now on high alert: the last time such a severe pattern was recorded, it led to the worst earthquakes the country has ever seen.

Over in Taiwan, already suffering from the effects of a devastating typhoon, a 5.8 'quake hit in the early hours of this morning.

But back in Indonesia, the authorities are increasingly worried: this morning a warning has been issued that the pattern of intensity is such that a much larger 'quake is likely.

Over at the other side of the Indian Ocean, recent activity has led to earthquakes off Sri Lanka and Bangladesh where ministers are worried that the country is ill prepared for serious activity.