Sumatra andaman island earthquake
On 26 December 2004, a strong earthquake was recorded under the Indian Ocean with the magnitude of 9.1. This earthquake is the largest event over Indian Ocean and among the three largest earthquake ever recorded in the 20th century. Sumatra-Andaman Islands earthquake consequently generated an enormous tsunami in the Indian Ocean.
The tsunami waves originated from this epicenter propagates further causing causalities and damages as far as to the African continent and killed over 227,000 innocent victims. Indonesia was the worst affected country with over 167,000 people were listed as dead or missing. Other countries that were also affected by the tsunami were Sri Lanka, India, Thailand, Somalia, Myanmar, Maldives, Malaysia, Tanzania, Seychelles, Bangladesh, South Africa, Yemen and Kenya.
The large number of fatalities caused by this event mainly due to its epicenter location which was located just offshore of a major coastal population center and lack of mitigation and response strategies for tsunami events.
effected countries
tsunami wave dissemination
The animation of the Sumatra-Andaman Islands tsunami wave height dissemination is shown as above, provided by Australian Government, Geoscience Australia. (click the image!)
Tohoku earthquake
Contrary to the Sumatra-Andaman Islands earthquake that happened over the Indian Ocean, 2011 Tohoku earthquake took place over the Pacific Ocean. The earthquake occurred off the Pacific coast of Tohaku, Japan with a magnitude of 9.0 and underwater depth of approximately 30 km. The epicenter was located approximately 70 kilometers east of the Oshika Peninsula of Tohoku. This earthquake is the strongest earthquake in Japan and the fourth most powerful earthquake ever recorded using modern record-keeping in 20th century. As of April, 2011 Japan’s National Police Agency confirmed total number of deaths was 15,891 with many more injured and missing.
Due to a huge release of energy by the earthquake, it consequently triggered a tsunami formation with a run-up height reaching to 45 meters tsunami waves which is responsible to bring destruction along the Pacific coastline of Japan’s northern islands. Even though several places in Japan were equipped with protective tsunami seawalls, the towering tsunami waves overpassed it and destroyed the tsunami seawalls. To further worsen the situation, the Tohoku tsunami also responsible to damage several nuclear reactors at the Fukushima Daiichi Nuclear Power Plant. It caused a cooling system failure which in turn resulted in a level-7 nuclear meltdown and release of dangerous radioactive to the surrounding. Recent finding detected a very low levels of radioactive chemicals originally from Fukushima at the coastal of Canada and California.
tsunami wave propagation
