Each continent is surrounded by a ledge of land that stretches as far as 1,300 kilometers offshore. These ledges are called the continental shelves, and in the Arctic these shelves underlie about two-thirds of the Arctic Ocean. This is not surprising since the Arctic Ocean is nearly landlocked, bordered by Greenland, Canada, Alaska, Russia and Norway. The average depth of the world's continental shelves is about 200 metres, but most of the Arctic continental shelves are at least 200 metres deeper than this. The difference is likely a result of the last glaciation; the weight of the ice pushed the northern continents down into the earth's crust. Since its removal, the earth has rebounded, but not enough time has passed for the continental shelves in the Arctic to reach their original depths.
Click on the links below to find out more about the continental shelves in the Arctic:
The Greenland shelf The European shelf The Alaskan shelf The Beaufort shelf The Siberian shelf