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Minggu, 31 Oktober 2010

EXISTING TSUNAMI SINCE 8000 YAERS AGO

An earthquake measuring 7.2 magnitude that rocked the Mentawai Islands, West Sumatra, Monday, October 25, 2010, causing a wave of deadly attacks, the tsunami. All the settlements are located on the west coast islands were hit by a tsunami that killed more than 400 people.
Indonesia is no longer familiar with the disaster. In December 2004, the great tsunami occurred in Aceh. Then the next three months occurred in Nias. One more year, exactly 17 July 2006, the tsunami also occurred in Pangandaran, West Java.
Tunami track record was already in place since 6000 BC. Scientific media page Livescience.com records list all-powerful tsunamis that have occurred on Earth.
6,000 BC
Large cluster in Sicily snow avalanches and falls into the sea. Landslide that occurred at 8 thousand years ago has sparked the tsunami spread across the Mediterranean Sea. There is no historical record of this disaster. Only the scientists estimate tsunami geology at 320 kilometers per hour has reached a height of 10 floors building.
1 November 1755
After the earthquake that destroyed Lisbon, Portugal, and shook much of Europe. Many people who take refuge in the boat. However, the tsunami would occur. No doubt this disaster killed more than 60 thousand people.
August 27, 1883
The eruption of Mount Krakatau in the Sunda Strait, triggering a tsunami that drowned coast of Sumatra, northern Java, and the Thousand Islands. Wave strength can drag coral weighing 600 tons to the beach. 36 thousand people have died in vain.
June 15, 1896
Waves as high as 30 feet emerged shortly after the earthquake in Japan. All of the tsunami that swept the east coast. 27 thousand people died.
1 April 1946
Large earthquake in Alaska cause big waves in Hawaii. Disasters are often referred to as the "mystery" April Fools tsunami "that killed 159 people.
July 9, 1958
8.3 Richter magnitude earthquake in Alaska sends out a wave of up to 576 meters in Lituya Bay, Alaska. It is the largest tsunami recorded in modern times.
Fortunately, the tsunami occurred in isolated places, so it does not cause many casualties. Tsunamis are only left two fishermen died, because the ship sank, hit by the waves.
May 22, 1960
The largest earthquake ever recorded of 8.6 magnitude in Chile. This earthquake created a tsunami that struck Chile Beaches within 15 minutes. High waves occur up to 25 meters. The tsunami killed 1,500 people in Chile and Hawaii.
March 27, 1964
Alaska Earthquake "Good Friday" measuring 8.4 magnitude, caused waves of 67 meters at Valdez Inlet region, Alaska. Wave at 640 kilometers per hour, killing more than 120 people. Ten of them were from the Crescent City, California, who also got sent waves as high as 6.3 meters.
August 23, 1976
Tsunami in the southwest Philippines killed at 8 thousand people. This great wave also triggered earthquakes in the vicinity of the beach.
July 17, 1998
An earthquake with magnitude 7.1 force generate a tsunami in Papua New Guinea. BESA wave quickly kill 2,200 people.
December 26, 2004
All-powerful earthquake with a strength of 9.3 magnitude rocked the Indian Ocean, off the west coast of Aceh. Largest earthquake during the last 40 years has led to high waves in North Sumatra, West Coast of Peninsular Malaysia, Thailand, the East Coast of India, Sri Lanka, even to the East Coast of Africa.
At least 320 thousand people from eight countries died. This disaster is the biggest death throughout history.
March 28, 2005
Three months later, tsunami also occurred in Sumatera. Off the coast of Nias Earthquake measuring 8.7 Richter which sparked a major tsunami that killed 1,300 people on Nias Island, West Sumatra.



THE CAUSE OF THE TSUNAMI 




Tsunamis can occur if an interruption occurs that causes the movement of large amounts of water, such as volcanic eruptions, earthquakes, landslides or meteorite that fell to earth. However, 90% of the tsunami is an earthquake under the sea. In recording the history of some of the tsunami caused by the volcano eruption, for example when the eruption of Mount Krakatoa.
Vertical movement on the earth's crust, can lead to the ocean floor rise or drop suddenly, which resulted in disruption of water balance that is above them. This resulted in the energy flow of sea water, which when it reached the coast into a large wave that caused the tsunami.
The speed of tsunami waves depends on the depth of the sea where the waves occurs, where the speed can reach hundreds of kilometers per hour. When the tsunami reaches the shore, its speed will be around 50 km / h and its energy is very damaging coastal areas in its path. In the midst of the tsunami wave height sea only a few centimeters to several meters, but when it reaches shore wave height can reach tens of meters due to a buildup of the water. When the tsunami reaches the coast of the mainland will crawl away from the coastline with a range of several hundred meters can even be a few kilometers.
This vertical motion can occur on the earth fault or the fault. The earthquake also occurred in the subduction area, where the oceanic plate menelusup down the continental shelf.
The landslide that occurred on the seabed and volcanic debris can also lead to disruption of sea water which can generate a tsunami. The earthquake caused perpendicular movement of the earth layer. As a result, the sea rose and fell abruptly so that the balance of sea water which is above them disturbed. Similarly, cosmic objects or meteor that fell from above. If the size of a meteor or landslide is big enough, can occur megatsunami reach hundreds of meters high.
The quake that caused tsunami

    
* An earthquake centered in the middle of the sea and shallow (0-30 km)
    
* An earthquake with a strength of at least 6.5 on the Richter Scale
    
* An earthquake with a pattern of reverse fault or fault down

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