Megatsunami

Very large wave created by a large, sudden displacement of material into a body of water

A megatsunami is an extremely large wave created by a substantial and sudden displacement of material into a body of water. Megatsunamis have different features from ordinary tsunamis. Ordinary tsunamis are caused by underwater tectonic activity (movement of the earth's plates) and therefore occur along plate boundaries and as a result of earthquakes and the subsequent rise or fall in the sea floor that displaces a volume of water.

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