Mid-ocean ridge that runs along the centre of the Atlantic Ocean, parallel to its edges, for some 14,000 km/8,800 mi almost from the Arctic to the Antarctic. Like other ocean ridges, the Mid-Atlantic Ridge is essentially a linear, segmented volcano.
The Mid-Atlantic Ridge runs down the centre of the ocean because the ocean crust has continually grown outwards from the ridge at a steady rate during the past 200 million years. Iceland straddles the ridge and was formed by volcanic outpourings.
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