Causes of Tsunami Tsunami can be caused by trauma or tremors in the sea floor and water for various reasons. These waves can be caused by strong earthquakes , volcanic eruptions, or the impact of asteroids or large meteorites. Pacific tsunamis are very common. Because half of the world's volcanoes are under this ocean. As a result of the tremor, the tsunami wave hit the coast without any warning. The epicenter was reported below the ground, however; no tsunami alert was issued.