Theroy of Seafloor Spreading

The theory of seas floor spreading was found when new ocean technology was invented to help scan the seasfloor. The technology helped to find the mid-ocean ridge, Rift Valley and trenches. Evidence that supports seasfloor spreading is the ocean bottom sediment, and seeig the rift valleys. Seafloor spreading is processed in the mid-ocean ridges, and it creates new crust on the Seafloor, it is caused by volcanic activity under water. The magma comes up through the Rift Valley and it hardens as it flows down the ridge.