On September 29 2009, a devastating natural disaster hit the islands of Samoa, American Samoa, and Tonga. An earthquake of magnitude 8.3 caused a massive tsunami to damage the surrounding islands.
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What was the cause of the tsunami?
A tsunami is a set of waves that is triggered by the displacement of water on the ocean floor [1]. On September 29th 2009, two particularly strong earthquakes caused a massive tsunami to hit the islands of Samoa, American Samoa, and Tonga [2]. An earthquake is the result of movement from tectonic plates on earth which causes the ground to shake [3]. The earth's outer most layer, the lithosphere, is made up of the crust and uppermost mantle [4]. The crust is made of rocks, makes up less than 1% of the earth and is the hard-outer layer of earth [5]. The mantle is the largest layer of the earth and consists of dense, heated rock [6]. The lithosphere is split into tectonic plates that slowly move due to the amount of heat from the earth's center causing molten rock to move in the mantle [7]. There are seven major plates and a large number of smaller ones on earth. The relative movement in which the tectonic plates meet, establishes the type of boundary (convergent, divergent, and transform) [8]. Along these boundaries are where earthquakes occur. When earthquakes occur on the convergent
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Unfortunately, a warning wasn't issued fast enough to warn American Samoa or Samoa about the incoming tsunami [14]. Tsunamis in the Pacific can move up to speeds of 805km per hour. The minutes between the earthquake and the tsunami didn't allow enough time to issue a warning or for emergency services to take action. It was recorded that there was more than one wave [19]. This means that after the first initial wave, several others followed though that were smaller and didn't cause as much