tsunami environmental_hazards A tsunami is a process during which a series of waves is generated in a water body, typically an ocean or large lake, by the displacement of a large volume of water. Earthquakes, volcanic eruptions and other underwater explosions (including detonations of underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami. tidal wave seismic sea wave mass liquid flow