This diagram shows the Americas being separated from the Europe and Africa as the seafloor spreads. Continents are grey in color. Youngest seafloor is red and as seafloor gets older it becomes yellow, green and then blue.
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NOAA/NESDIS/National Geophysical Data Center, Boulder, CO.

Seafloor Spreading

This picture explains how seafloor spreading works! It shows the ages of ocean floor in the Atlantic and eastern Pacific Oceans.

The red sections are the newest area of the seafloor. They are at mid-ocean spreading ridges. These are places at the bottom of deep oceans where there is a crack between two plates and new lava comes to the surface from deep within the Earth.

As new seafloor forms at the spreading ridges, older parts move away from the ridge. The blue areas are the oldest. Sometimes the oldest parts of the seafloor are next to land and sometimes they are near places where subduction is happening.

Last modified February 4, 2008 by Becca Hatheway.

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