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What causes most tsunamis?
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tsunami
Aftermath of the December 2004 tsunami in Aceh, Indonesia.
Most tsunamis are caused by earthquakes that occur at or beneath the ocean floor. Specifically, a tsunami is generated when a strong earthquake causes a violent vertical displacement of the seabed, which in turn displaces a large volume of water.12
While earthquakes are the primary cause, other geological events can also trigger these waves, including:
- Submarine or coastal landslides: These can occur independently or be triggered by an earthquake.32
- Volcanic eruptions: Large eruptions along shorelines can displace significant amounts of water.12
- Extraterrestrial impacts: The impact of a meteor or comet into a body of water can also produce a tsunami.13
It is important to note that not all earthquakes produce tsunamis; for instance, if a fault slips horizontally rather than thrusting upward, the water column is typically not disturbed enough to create a wave.1