#938
Keymaster

The geography/topography of the Pacific islands is interesting, and can determine how they respond to particular natural disasters. Where there are small atolls, built on limestone cones coming out of the deep water, apparently these (almost illogically) when exposed to tsunamis, may not be hit by massive waves. This happened in the Maldives (west of Sri Lanka) during the 2004 Indian Ocean earthquake/water. The fast tsunami waves (travelling at up to 500 kph in deep water) were only 1/2 metres went they swept thru’ these islands (ie there wasn’t time to slow down, and rise in height). In Tonga conversely (and particularly the main island), where this is primarily low-lying limestone (and no obvious mountains to seek refuge in), the earthquake/tsunami models predict massive destruction in the capital Nuku’alofa, as the waves would be slowed down by the land mass and rise in height (eg up to 5-10 metres). You’re correct, Matt, for other Pacific volcanic islands, where people can potentially flee to high ground if they either hear the earthquake (when relatively near), and are warned through the early warning networks (for earthquakes generates hundreds of kms away). It’s an interesting subject !