Understanding Tsunamis
Tsunamis are powerful ocean waves that can cause significant destruction when they reach coastal areas. They are primarily triggered by specific geological events.
Key Causes of Tsunamis:
- Earthquakes:
Most tsunamis are caused by underwater earthquakes, especially those that occur in tectonic plate boundaries. When the ocean floor shifts suddenly, it displaces a large volume of water, creating waves that can travel across entire ocean basins.
- Volcanic Eruptions:
Underwater volcanic eruptions can also trigger tsunamis. When a volcano erupts, it can send debris and gases into the water, displacing water and generating waves.
- Landslides:
If a large landslide occurs near or under the ocean, it can push water away, resulting in tsunami waves. This can happen from coastal landslides or from underwater landslides.
Other Factors Not Causing Tsunamis:
- Tidal Changes:
Tsunamis are not caused by regular tidal changes. Tides are a result of the gravitational pull of the moon and sun, which do not create the sudden displacement needed for a tsunami.
- High Winds:
While high winds can create regular ocean waves, they do not cause tsunamis. Tsunamis are created by the rapid movement of large volumes of water, not by wind.
- Heavy Rainfalls:
Heavy rain can lead to flooding but does not directly cause tsunamis. Tsunamis require sudden geological activity beneath the ocean.
In summary, the correct answer is option 'C' because tsunamis are predominantly triggered by earthquakes and volcanic eruptions under the sea.