Maldives

The Maldives consists of 26 atolls stretched along the Laccadive-Chagos Ridge in the central Indian Ocean, an ancient hotspot trail built by the passage of the Indian Plate over the Reunion mantle plume approximately 60 million years ago. The ridge itself is now geologically quiet, and the Maldives experience very low levels of local seismicity. There are no active tectonic [[fault]] systems beneath the atolls, and local earthquake generation is minimal. The seismic hazard to the Maldives is almost entirely from distant sources — primarily the Sunda [[subduction-zone]] to the northeast and the Carlsberg Ridge spreading system to the west.

The defining seismic event for the Maldives was not a local earthquake but the December 26, 2004 Sumatra-Andaman earthquake (magnitude 9.1), which generated a devastating [[tsunami]] across the Indian Ocean. The Maldives, sitting at low elevations barely above sea level, were severely affected. Wave heights of 2–4 metres inundated multiple atolls, killing 82 people, displacing 12,000, and destroying the livelihoods of fishing communities. The damage demonstrated the extreme vulnerability of the Maldives to Pacific and Indian Ocean tsunamis, even when generated thousands of kilometres away. The country's maximum elevation of only about 2.4 metres above sea level means that [[tsunami]] inundation is the dominant natural hazard rather than ground shaking.

The geological foundation of the Maldives is entirely of volcanic and biogenic carbonate origin — the limestone platforms of the atolls are built atop ancient submerged volcanic seamounts. The underlying Indian Plate is among the most geologically stable crustal masses on the planet, having been moving northward as a coherent unit for over 60 million years. The plate's interior is far from any active plate boundary, and the thickness and rigidity of the lithosphere under the central Indian Ocean mean that stress accumulation sufficient to generate local earthquakes is minimal. The primary seismic risk management challenge for the Maldives is [[tsunami]] preparedness, early warning reception, and vertical evacuation planning, given the impossibility of horizontal evacuation to high ground on most atolls.