Earthquake 'the equivalent of million atomic bombs'

SCIENTISTS describe the devastating earthquake off the island of Sumatra as a "megathrust" - a grade reserved for the most powerful shifts in the Earth's crust and the equivalent of one million atomic bombs.

The term does not entirely capture the awesome power of the fourth-largest earthquake since 1900, or the tsunami catastrophes it spawned for coastal areas around the Indian Ocean.

Despite its awesome power, the quake itself was not much of a surprise, scientists said.