The Sumatra–Andaman earthquake ruptured roughly 1,300 kilometres of fault in about ten minutes, one of the longest ruptures ever recorded. It displaced an enormous volume of water and generated waves that reached 30 metres in parts of Aceh.
Banda Aceh was struck within 20 minutes; Sri Lanka, India and Thailand about two hours later; Somalia after seven hours. There was no Indian Ocean warning system, and in most affected areas people had no cultural memory of tsunami or knowledge of the natural warning sign — rapidly receding water.
Around 227,000 people died across 14 countries, including roughly 170,000 in Indonesia alone. The disaster led directly to the creation of the Indian Ocean Tsunami Warning System and a global expansion of coastal warning infrastructure and education.
Why this event still matters
Historical incidents shape the rules that protect people today — building codes, evacuation policy, warning systems and inspection regimes almost always trace back to a specific disaster. Studying Indian Ocean Tsunami alongside current events is how preparedness improves.
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