Causes of Tsunamis
Tsunamis occur when there is a sudden large displacement of water. There are three main causes of tsunamis: seismic activity, submarine landslides, and cosmic impacts.
- Seismic Activity
Seismic activity is the most common cause of tsunamis. Both tectonic and subduction earthquakes in and near the ocean may create tsunamis. During a tectonic earthquake, the sea floor becomes deformed, forcing a displacement of water. In a subduction earthquake, tectonic plates slip under each other, creating a massive disturbance, also resulting in a significant displacement of water.
- Submarine Landslides
Submarine landslides can also cause tsunamis. Submarine landslides occur during earthquakes and the implosion of underwater volcanoes. The falling sediment and rock in these landslides can also trigger massive water movement, resulting in a tsunami.
- Cosmic Impacts
Cosmic impacts in the ocean are the least frequent cause of tsunamis. This is similar to throwing a rock into a pond, except on a much larger scale. When the rock hits the water, it creates small ripples of water moving away from the point of impact. In a cosmic impact, these ripples would instead be massive tsunamis, increasing in size as they near the shore.