A ridge under the Atlantic Ocean was first inferred by Matthew Fontaine Maury in 1850. The ridge was discovered during the expedition of HMS Challenger in 1872.[2] A team of scientists on board, led by Charles Wyville Thomson, discovered a large rise in the middle of the Atlantic while investigating the future location for a transatlantic telegraph cable.[3] The existence of such a ridge was confirmed by sonar in 1925[4] and was found to extend around the Cape of Good Hope into the Indian Ocean by the German Meteor expedition.[5]
In the 1950s, mapping of the Earth’s ocean floors by Bruce Heezen, Maurice Ewing, Marie Tharp and others revealed that the Mid-Atlantic Ridge had a strange bathymetry of valleys and ridges,[6] with its central valley being seismologically active and the epicenter of manyearthquakes.[7][8] Ewing, Heezen and Tharp discovered that the ridge is part of a 40,000-km-long essentially continuous system of mid-ocean ridges on the floors of all the Earth’s oceans.[9] The discovery of this worldwide ridge system led to the theory of seafloor spreading and general acceptance of Wegener's theory of continental drift and expansion in the modified form of plate tectonics. The ridge is central to the breakup of the hypothetical supercontinent of Pangaea that began some 180 million years ago.