Who discovered seafloor spreading?

Harry Hammond Hess, a geologist and Navy submarine commander (who later rose to the rank of Rear Admiral), proposed the theory of seafloor spreading. He proposed that the continental movement is a result of the spreading of the seafloor. In other words, it is the seafloor that is pushing the continents apart from each other. This work provided the much-needed mechanism for the "continental drift" theory proposed by Alfred Wegener.
According to Hess, the Mid-Atlantic Ridge (an ocean ridge found along the floor of the Atlantic Ocean), is the location where new seafloor was being added to the Earth's lithosphere. This, in turn, pushed the continents apart. This also helped to explain how the Atlantic Ocean can get wider without dramatically changing the coastlines of the landmass.
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