How Tsunamis Work

[n2doc]

By LiveScience Staff
posted: 27 February 2010 08:49 am ET

A tsunami is not a single wave, but a series that behave much like the waves rippling out from a stone dropped in a pond. Each wave can last five to 15 minutes, and the danger can last for hours after the initial wave arrives.

"Tsunami waves heights cannot be predicted and the first wave may not be the largest," according to today's NOAA statement.

Tsunamis, which can travel over the ocean surface from many hundreds of miles, can be generated when chunks of the planet's crust separate under the seafloor, causing an earthquake. Here's what happens: One slab of lifting crust essentially rapidly acts as a giant paddle, transferring its energy to the water.

Tsunamis can also be caused by volcanic eruptions, underwater detonations and even landslides.

more

http://www.livescience.com/environment/how-tsunamis-work-100227.html