CBSE Class 7 Answered

On Sunday morning 26 December 2004, a massive earthquake measuring 9.1 on the Richter scale struck off the west coast of Sumatra, Indonesia. The epicentre was 30 kilometres under the seabed and approximately 250 kilometres south to south-west of Banda Aceh. The earthquake generated a series of towering waves which could travel at 80 km/h in shallow water, with the largest impact felt in Indonesia and Sri Lanka. In the nine hours following the earthquake, 14 aftershocks with magnitudes between 5.7 and 7.3 occurred along the arc from Sumatra towards Nicobar and the Andaman Islands.

Within 15 minutes of the earthquake, waves began striking the coasts of northern Sumatra and the Nicobar islands.Waves of up to 30 metres were recorded as the tsunami swept through Aceh, the hardest hit region of Indonesia. Around two hours after the earthquake struck, waves reached Sri Lanka, India and Thailand. An hour later they reached the Maldives, and, more than seven hours after the initial quake, the tsunami was observed in Mauritius and along the east coast of Africa.

The tsunami waves caused widespread death and injuries, displaced thousands, destroyed towns, homes, livelihoods, infrastructure, and wrecked coastal areas. Twenty six Australians lost their lives. Due to the scale of destruction estimates for total lives lost vary, according to the United Nations approximately 227,000 people were killed in fourteen countries. Data published by the Tsunami Evaluation Coalition indicated at least 275,000 people were killed. Across the region there are still people believed to have been swept away who have never been accounted for. Measured in lives lost, this makes it one of the 10 worst earthquakes in recorded history, as well as the single worst tsunami in history. 

The worst affected countries were India, Indonesia, Malaysia, Maldives, Myanmar, Sri Lanka, Seychelles, Thailand and Somalia.