Consider the following statements regarding Waves and Tsunamis:

1. Tsunamis can be caused by undersea earthquakes, volcanic eruptions, underwater landslides, or asteroid impacts.

2. Wind-generated ocean waves transfer energy across the water, but water particles themselves do not move forward significantly.

3. The speed of a tsunami decreases as it approaches shallow coastal waters due to the rise in wave height.

4. Unlike regular waves, tsunamis have long wavelengths, which make them almost undetectable in deep oceans.

Which of the above statements are correct?