On 26 December 2004, at 07:58:53 local time (UTC+7), a Mw 9.2–9.3 earthquake struck with its epicenter off the west coast of Aceh, in northern Sumatra, Indonesia. The undersea megathrust earthquake, known in the scientific community as the Sumatra–Andaman earthquake, was caused by a rupture along the fault boundary between the Burma plate and the Indian plate, and reached a maximum Mercalli intensity of IX in some areas.
The earthquake caused a massive tsunami with waves up to 30 m (100 ft) high, referred to by British and Commonwealth media as the Boxing Day tsunami, after the Boxing Day holiday, or the Asian tsunami, which devastated communities along the surrounding coasts of the Indian Ocean, killing an estimated 227,898 people in 14 countries, especially in Aceh in Indonesia, Sri Lanka, Tamil Nadu in India, and Khao Lak in Thailand. The direct result was severe disruption to living conditions and commerce in coastal provinces of these and other surrounding countries. It is the deadliest tsunami in history, the deadliest natural disaster of the 21st century, and one of the deadliest natural disasters in recorded history. It is also the worst natural disaster in the history of Indonesia, the Maldives, Sri Lanka, and Thailand.
The earthquake itself is the most powerful earthquake ever recorded in Asia, the strongest of the 21st century, and the second- or third-most powerful globally since modern seismography began in 1900. It had the longest fault rupture ever observed, be
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 2004 Indian Ocean earthquake alongside current events is how preparedness improves.
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