Sea-floor spreading refers to the splitting of the ocean floor thereby leading to the expansion of the seas and oceans. This process adds new materials to the ocean floor along the mid-oceanic ridge. This idea of sea floor spreading allowed the scientists to demarcate that the rocks that are present along the mid oceanic ridge are the younger and the rocks that are present away from the rocks are the older rocks.
Along the mid-oceanic ridge, the rocks are comprised of magnetic strips that shifts their orientation every time it erupts. This separation of sea floor takes place due to the plate tectonic movement. It generates earthquakes of various intensities in the subduction zone. The rocks of the oceanic crust are basaltic in nature and are very dense compared to the continental crust.
