| 3.316°N, 95.854°E 26th December 2004 00:58:53 UTC |
| Please visit the Disasters Emergency Committee website |
 Click for animation |
| Graphics & information from the U.S National Earthquake Information Centre & the U.S. Geological Survey Earthquake Hazards Program |
| This should be a link to the International Hazard Warning Centre. Unfortunately it doesn't exist. Yet. |
| Historical Context | ||||
| Magnitude | Year | Location | Tsunami | Est. Deaths |
| 9.5 | 1960 | Chile | 25m (10m Hilo, Hawaii). | +2,000 |
| 9.2 | 1964 | Prince William Sound, Alaska | Local waves* at 70m | 131 |
| 9.1 | 1957 | Andreanof Islands, Alaska | 16m Kauai, Hawaii | 0? |
| 9.0 | 1952 | Kamchatka | 15m | +14,000 |
| 9.0 | 2004 | Andaman & Nicobar Isles | 30m? | +250,000 |
| 7.8 | 1976 | Tangshan, China | No | +240,000 |
| * Generated by landslides | ||||
| What Happened? | |
| A 400mile strip of the sea floor moved and pushed a large volume of water causing a tsunami. These waves bounced around the Indian Ocean for a few hours decimating coastal regions of at least ten countries, killing more than 250,000 people and placing at least a million in immediate peril. An estimated 10 million people were made homeless. |  |
| The sea floor moved. Why? It moves all the time here, about 6 centimetres a year on average. The massive slab of rock (called a plate) that India and most of the Indian Ocean sit on is pushing against a group of much smaller plates that make up Myanmar and the Andaman and Nicobar Isles. | |
| The Indian plate dives beneath the smaller plates along a line called a subduction zone. As the plate grinds its way downwards it frequently gets stuck at points along this subduction zone. The release of this trapped energy is called an earthquake. If the two surfaces get stuck for just a few days or months and at just one or two points (say 1km of the subduction zone) then the resulting earthquake would probably be very small, something like a very large lorry driving past your house for 20 seconds or so. | |
| If almost one thousand kilometres of a subduction zone gets stuck for about 40 years and then releases this trapped energy (that's what probably happened on the 26th) then the energy released is going to be phenomenal. If your house was within spitting distance of a magnitude 9 earthquake, almost regardless of how it was constructed - it would be reduced to rubble. | |
| But luckily on 26th December 2004 there were few houses within the distance, and relatively few people would have been killed by the earthqake itself. | |
| Unfortunately there was a very large volume of sea water above the earthquake and the resulting tsunami destroyed the livelihoods of hundreds of thousands of people. | |
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The image on the left is from the UK Hydrographic Office and the Royal Navy. It shows part of the plate boundary after the earthquake. Water depth ranges from 1,000m (red) to 4,000m (purple).
Further information on this survey may be found at the UK Hydrographic Office website. |
| Please visit the Disasters Emergency Committee website |