This image shows the age of the ocean bottom near the Mid-Atlantic Ridge--you can find Iceland off the east coast of Greenland (and this ridge runs right through Iceland). Red indicates rock about 20 million years old; to see all of Earth's surface, and the whole color key, check out Crustal Age of the Ocean Floor. To understand how the theory of plate tectonics explains the Mid-Atlantic Ridge, visit This Dynamic Earth: Developing the Theory.
Image:
image credit: Mr. Elliot Lim, CIRES & NOAA/NGDC; image source (see first four files); larger image
