Another series of huge earthquakes have rocked the South Pacific. When you're getting into 7.8 and 8.0 territory, you're talking city destruction time ... except these occurred under the sea ... I shudder to think what one of these quakes would do if it hit in Southern California. To put it into context, the great 'quake that hit San Francisco in 1906 is estimated to have been about 7.8. The one in 1989 was only 6.9. The 1994 Northridge earthquake was only 6.7, but here's how it has been described:

The earthquake occurred on a blind thrust fault, and produced the strongest ground motions ever instrumentally recorded in an urban setting in North America. Damage was wide-spread, sections of major freeways collapsed, parking structures and office buildings collapsed, and numerous apartment buildings suffered irreparable damage. Damage to wood-frame apartment houses was very widespread in the San Fernando Valley and Santa Monica areas, especially to structures with "soft" first floor or lower-level parking garages. The high accelerations, both vertical and horizontal, lifted structures off of their foundations and/or shifted walls laterally.

Let's all hope that we don't see anything like an 8.0 in a major urban area.