Pacific 'Ring of Fire' unleashes another killer quake

Whether on land or undersea, the volatile edges of the north Pacific, bounded by the east Asian rim and the west coast of the Americas, are alive with near-constant seismic activity.

Some of the most dramatic natural disasters of recent history have happened within the Ring's arc, which stretches from Chile, north to Alaska and then west to encompass Japan, Southeast Asia and the Pacific islands.

From the nuclear-like explosion of Krakatoa volcano off the coast of Indonesia in 1883 to the Indian Ocean tsunami disaster that killed 220,000 in late 2004 the Ring's awesome power is legend.

The eruption of Mount St Helens in the United States in 1980, the freak quake that felled San Francisco in 1906 and the one that devastated Kobe, Japan, in 1995, were all part of the Ring's devastating toll.

Since the start of the year there has been an increase in seismic activity with dozens of earthquakes and a volcanic eruption within the Ring.