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Samoan Tsunami Essay

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Samoan 2009 tsunami report:
What caused the earthquake and tsunami?
On Tuesday the 29th of September 2009, a huge tsunami hit Samoa – as well as several other islands – and impacted many, leaving a path of destruction [1]. Tsunamis are big waves that are generated from earthquakes, or volcanic eruptions that occur in the ocean [2]. The tsunami – in the case of Samoa – was caused by an underwater earthquake [1]. An earthquake is when the Earth’s surface shakes in response to the sudden release of energy in its lithosphere which then creates seismic waves [3]. There were two earthquakes that occurred before the tsunami; this is known as a ‘triggered duplet” [4].
The first earthquake was a magnitude 8.1, the second an 8.0. The first triggered
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In the case of Samoa, the oceanic plate bent as it entered the trench. The bend of the plate elevates the ocean floor and makes a shape known as the outer rise that is parallel to the ocean trench. The bend of the plate results in strains in the oceanic crust, which can lead to normal faults. The Samoan earthquake was located around the northern terminus of the Tonga volcanic arc where the trench has a sharp bend going west. The earthquake happened just east of this trench. The Pacific plate entered the subduction zone and made a steep descent downward, as the subduction is quite dense and old. This then resulted in faults near the Tongan Trench…show more content…
Both were impacted terribly and suffered the loss of lives, but Samoa seemed to come out of it the worst. Firstly, the first wave arrived only 10 minutes after the earthquake in Samoa. However, American Samoa had 20 minutes until the first wave. This gave them more warning and time to evacuate to higher grounds. Also in Samoa the height above sea level was 14 m however in American Samoa it was 10m [14]. While being quite close in distance, Samoa is an independent country while American Samoa is supported by the American government. This means that American Samoa has better quality buildings and house’s that would be sturdier in an earthquake as well as the support of America
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