Tsunami Essay

892 Words 4 Pages
The movement of earth's crust is capable of shifting huge volumes of water, then it unleashes great and powerful waves. Among nature's most powerful forces of destruction, these waves are called tsunamis. The Japanese term means "harbour waves". Tsunamis are a series of large ocean waves of extremely long wavelength and a period which is suddenly displaced on a massive scale by an underwater disturbance such as an earthquake occurring on or near the seabed or a volcanic eruption. Tsunamis hit the coastal regions approximately 10 times each year. Tsunamis are often the main cause of death associated with the earthquake in the coastal region. There are four stages of tsunami formation namely initiation, split, amplification and lastly, run up …show more content…
During this stage, the seismic energy from an offshore earthquake forces out a mass of seawater when the waves start. The undersea earthquake happen. The undersea earthquake or also known as the submarine earthquake is the underwater tectonics of plate or shifting plates of the earth crust. Two blocks of the ocean floor slip past one another and bumping into each other. The reason is the surface of Earth or lithosphere (first two internal layers of Earth) consist tectonic plates which about 50 km to 140 km thick and continuously moving slowly upon a bed of magma in the asthenosphere (third internal layer of Earth) (Pasyanos, 2008). This sudden shift of the plates called fault plane produces a massive energy of waves above sea …show more content…
The water column moves up above sea level. It is when the waves move apart from each other. One wave moves out into the ocean and the other wave moves toward the beach or closest land. Then, the energy is forced out by gravity horizontally at the surface. Tsunami does not show the water movement but the movement of energy through the water. Then wave splits into two waves created by the force from the disturbance, one moves into the deep ocean that is also known as distant tsunami and one move towards the nearest shore that is also known as a local tsunami. The height of the two travelling tsunamis is about half the height of the real sea level. The speed of tidal wave that goes towards the ocean travels quicker than the one heading to the coast (Back, 2011). Therefore, the local tsunami near shore travels slower than the deep-ocean

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