Tsunamis are generated when underwater earthquakes move the plates of the ocean floor. This results in formation of waves, which can have a speed of up to 700-800 km/h. In the ocean, these waves pass unnoticed, because of the relatively small height of the waves. However, when they are near the shore, at lower water depths, we observe huge waves moving at a rapid pace. Tsunamis are a destructive force of the nature. They uproot (and destroy) anything that comes in their path, including human beings, houses, cattle, vegetation (including trees and crops), etc. The force of tsunamis is what changes the landform. On land (near shore), erosion takes places due to force of rushing water. The sea is, on the other hand, littered with all the debris generated by the tsunami.
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