Q:

What causes a tsunami?

A:

Quick Answer

Tsunamis are caused by undersea volcanoes or earthquakes that push massive amounts of energy through the water. Earthquakes are the most common cause, but landslides can create tsunamis as well.

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What causes a tsunami?
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Full Answer

Earthquake tsunamis begin when subduction occurs, a process where larger undersea plates slide under a lighter plate. In certain cases, the lighter plate shifts upward suddenly, stemming from the pressure of the other plate. This sends shoots of rocks upward, transferring powerful energy through the water and above sea level. The gravity forces the energy out in a horizontal fashion and along the surface, the equivalent of a ripple effect that is seen when an object is thrown into the water.

The energy spreads away from the disturbance area. The energy transfer formulates the tsunami, but the size depends on the water levels, since tsunamis travel faster in deeper waters. Tsunamis can travel in deep waters at hundreds of miles per hour. Tsunamis slow down when reaching land but increase in height. Tsunamis are usually no higher than 3 feet until the waves approach land.

In the case of landslide tsunamis, large amounts of sediment fall into the ocean at rapid speeds, forcing powerful energy levels into the water. The sudden energy travels at a faster speed than the water can absorb, causing tsunamis to develop.

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Related Questions

  • Q:

    When was the first tsunami?

    A:

    According to Eden, the first recorded tsunami occurred off the coast of Syria over 4,000 years ago. The Storegga Slides is a famous event that occurred in the prehistoric era that may have been caused by a tsunami.

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  • Q:

    What happens after a tsunami hits?

    A:

    After the initial wave hits land, a large wall of water follows closely behind it. The water slams into the land, then immediately begins to recede, taking many objects on land with it.

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  • Q:

    What happens during a tsunami?

    A:

    When a tsunami occurs, it's typically in response to an earthquake, and oceanic waves grow to large proportions, increasing their rate of causing damage. Other natural earth forces can cause tsunamis as well, including meteorites, landslides, explosions and a volcano erupting, according to the Australian Bureau of Meteorology or BOM.

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  • Q:

    How do you prepare for a tsunami?

    A:

    Before a tsunami is imminent, people living in areas where tsunamis are possible should construct tsunami emergency kits and organize a family communications plan. When a tsunami watch is issued, people should tune into the National Oceanic and Atmospheric Administration's weather service, ensure the emergency kit is well stocked, locate family members and prepare to evacuate. When a tsunami warning is issued, everyone should evacuate to higher ground.

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