Skip to main content
U.S. flag

An official website of the United States government

Life of a tsunami

By Pacific Coastal and Marine Science Center
Illustration shows a cross-section of a coastline and the beginnings of a tsunami wave that is caused by an earthquake.
Original Thumbnail Medium

Detailed Description

Life of a tsunami: Panel 1—Initiation

Earthquakes are commonly associated with ground shaking that is a result of elastic waves traveling through the solid earth.

However, near the source of submarine earthquakes, the seafloor is "permanently" uplifted and down-dropped, pushing the entire water column up and down. The potential energy that results from pushing water above mean sea level is then transferred to horizontal propagation of the tsunami wave (kinetic energy). For the case shown above, the earthquake rupture occurred at the base of the continental slope in relatively deep water. Situations can also arise where the earthquake rupture occurs beneath the continental shelf in much shallower water.

Note: In the figure, the waves are greatly exaggerated compared to water depth. In the open ocean, the waves are at most several meters high spread over many tens to hundreds of kilometers in length.

Sources/Usage

Public Domain.

Related

link
A sign at a beach warns that it's a tsunami hazard zone and that in case of earthquake to go to high ground or inland.

Tsunamis and Tsunami Hazards

You don't hear about tsunamis very often, but when they do strike, they can be huge newsmakers and can have drastic and devastating effects. The occurrence and potential for tsunamis on the coasts of the United States is not out of the question. Read on to learn about tsunamis.
link

Tsunamis and Tsunami Hazards

You don't hear about tsunamis very often, but when they do strike, they can be huge newsmakers and can have drastic and devastating effects. The occurrence and potential for tsunamis on the coasts of the United States is not out of the question. Read on to learn about tsunamis.
Learn More

Related

link
A sign at a beach warns that it's a tsunami hazard zone and that in case of earthquake to go to high ground or inland.

Tsunamis and Tsunami Hazards

You don't hear about tsunamis very often, but when they do strike, they can be huge newsmakers and can have drastic and devastating effects. The occurrence and potential for tsunamis on the coasts of the United States is not out of the question. Read on to learn about tsunamis.
link

Tsunamis and Tsunami Hazards

You don't hear about tsunamis very often, but when they do strike, they can be huge newsmakers and can have drastic and devastating effects. The occurrence and potential for tsunamis on the coasts of the United States is not out of the question. Read on to learn about tsunamis.
Learn More
Was this page helpful?