The NASA Earth Observatory has a facinating look at the mechanics of what happened in this horrific disaster which took place in SE Asia. The PDF shows why it is critical that a tsunami warning system is emplaced in the Indian ocean such as that which is in the Pacific. The area has five converging tectonic plates, the Eurasia plate, Australian plate, India plate, Sunda plate and the Burma microplate. The India Plate and the Burma Microplate meet along the Sunda trench to the west of Sumatra. On the 26th, the India Plate subducted, i.e. slipped underneath, the Burma Plate,...