2004 Indian Ocean Earthquake
The Indonesian earthquake of 2004 was one of the costliest and most destructive events in history. The earthquake, and subsequent tsunami, killed over 200,000 people, destroyed thousands of homes, and impacted people as far away as South Africa.
The earthquake itself was a magnitude 9.3 quake. It happened on December 26, 2004, just off the coast of Sumatra, Indonesia. In about 10 minutes, nearly 1000 miles of a fault along the boundary of the Indian Plate and the Burma Plate slipped 50 feet. The Indian Plate is subducting under the Burma Plate, and this sudden, intense movement released stresses that had been building up for years. Sea level was raised by a fraction of an inch, and the entire planet oscillated by a similar distance. The earthquake itself was not the most damaging or deadly event of the day. Due to the fault and motion of the seabed, nearly 7 cubic miles of water were displaced, leading to a massive tsunami which propagated throughout the entire world.
Tsunamis are waves that are formed from displacements of the sea. They can vary from microscopic in height to over 100 feet. The tsunami created by the Indonesian quake was estimated to be 100 feet in a number of locations. A series of enormous tsunami waves hit numerous populated areas, destroyed thousands of homes and lives. In fact, small tsunamis were measured around the world, in places such as Canada and Mexico. Just prior to a tsunami’s strike, water retreats from the beaches, since the trough of the wave reaches shore first. Then, the large wave breaks and rolls onto the shore. Its progress is hampered by trees and coral reefs; however, many governments in the impacted areas had destroyed coral reefs just off shore. The wave progressed inland, decimating everything in its path. Many houses in these areas were built near the shore and did not have any reinforcement. People were not aware of the signs of impending tsunamis. Some even went down to the beach to take pictures of the retreating water.
To help prepare for future events of this nature, people living in low lying regions along a coast should be informed of the main warning sign of a tsunami – retreating ocean water directly after an earthquake strikes. They should be taught to run for higher ground. In addition, various preventative measures can be taken by local governments to make their coastlines safer. For example, many people believe that planting trees directly at the shore will cause a great deal of the tsunami’s energy to be absorbed before reaching population centers just inland. Governments should not purposely destroy coral reefs, which are quite protective.
In conclusion, a fault in a subduction zone set up the 2004 Indonesian earthquake. The earthquake, in turn, created a megatsunami, killing hundreds of thousands of people. There are many steps that can be taken to try to lessen the impact of similar future events.
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