Post on 04-Jan-2016
Tsunami
Tsunami is a Japanese word
Movement of seafloor during an earthquake produces a surge of water that becomes a long sea wave
Tsunami
A tsunami only a few centimeters in the open ocean can produce waves that are many meters high on shore
Tsunami
A tsunami only a meter high in the open ocean can produce waves that are many tens of meters high on shore
Tsunami
A tsunami wave can travel thousands of miles and still cause staggering damage
Tsunami
Tsunami Barrier in Taro, JapanThe Japanese have built giant waves barriers in several areas
Southeast Asia Tsunami 2004The worst tsunami in recorded history was created at 7:58 am on December 26, 2004
Magnitude 9.3 (second strongest earthquake ever recorded on a seismograph)
Lasted 10 minutes (longest lasting earthquake in history)
Southeast Asia Tsunami 2004229,866 confirmed dead, which includes 42,883 missing and never accounted for
More than $7 billion dollars damage
Southeast Asia Tsunami 2004This earthquake was unusually large in geographical extent
An estimated ~1,600 km (~1,000 mi) of fault line slipped up to 15 m (50 ft) along the subduction zone where geologist believed that the Indo-Australian plate dives under the Eurasian plate
However, research into this tsunami lead to the discovery of the Burma microplate
Southeast Asia Tsunami 2004Scientist now understand that the very large India and Australian plates are being subducted under the very small Burma microplate
The massively bigger India and Australian plates easily “shove” the smaller Burma microplate around
Southeast Asia Tsunami 2004Seismographic data revealed that the first phase involved a rupture about 400 kilometers (250 miles) long and 100 kilometers (60 miles) wide, located 30 kilometers (19 miles) beneath the sea bed, which is the longest rupture ever known to have been caused by an earthquake
Southeast Asia Tsunami 2004The rupture proceeded at a speed of about 10,000 km/h (6,300 mph), beginning off the coast of Aceh and proceeding north-westerly over a period of about 100 seconds
Southeast Asia Tsunami 2004Then a pause of about 100 seconds took place before the rupture continued northwards towards the Andaman and Nicobar Islands
There was a vertical change along the rupture that ranged from a few meters up to 50 meters
Southeast Asia Tsunami 2004
The sea bed is estimated to have risen by several meters, displacing an estimated 30 cubic kilometers (7 cubic miles) of ocean water and triggering devastating tsunami waves
Southeast Asia Tsunami 2004The tsunami waves did not originate from a point source, but rather radiated outwards along the entire 1,600 kilometer (1,000 mile) length of the rupture
Southeast Asia Tsunami 2004Actually, there were four tsunami waves that came ashore over a 90 minute time period
The resulting tsunamis devastated the shores of Indonesia, Sri Lanka, India, Thailand and other countries with waves as high as 30 meters (100 feet)
Southeast Asia Tsunami 2004These tsunamis caused serious damage and deaths as far as the east coast of Africa, with the farthest recorded deaths due to the tsunami occurring in Struisbaai , South Africa, 8,000 kilometers (5,000 miles) away from the epicenter, where a 1.5 meter (5 foot) wave surged on shore during high tide about 12 hours after the earthquake
Southeast Asia Tsunami 2004The US military provided the first foreign aid, but it took a week before help reached all of the stricken
Southeast Asia Tsunami 2004
A plot showing all of the aftershocks of magnitude 4.0 and greater that occurred over a 15 day period between December 26, 2004 and January 10, 2005
Southeast Asia Tsunami 2004The tsunami-lashed Andaman and Nicobar Islands suffered 9,500 aftershocks between December 26 and February 19