I was in bed, late at night, in my apartment in Kuala Lumpur, about 3 months after the huge Tsunamigenic 9.1 magnitude quake near Nias island. The bed began to rock significantly, of its own volition, the venetian blinds rattled on the windows, the chandelier swayed. Classic Surface wave response. It was immediately MUCH more than a passing truck. The shaking strengthened to the point where I took shelter in a doorway - MMI Intensity was IV to V, and continued for a duration of about 25 seconds in all.

Looking at the direction of the chandelier's motion, I could point back East towards the tip of Sumatra, and the duration of the surface wave motion gave me an estimate of 1000 km distance to the epicentre.

That was one hell of a quake - 8.6, according to the USGS website, but "only" 1300 people were killed - mostly because nearly every building in the epicentral zone had already been wrecked by the Boxing day quake.

It really frightened me that I had experienced such strong effects, at a distance of 100 km. What must it have been like to be close to the focus?