Plate Tectonics Questions Medium
Seafloor spreading is the process by which new oceanic crust is formed at mid-ocean ridges and spreads outwards, creating new seafloor. It occurs due to the movement of tectonic plates, specifically the divergent plate boundaries where two plates move away from each other.
The process begins with the upwelling of hot mantle material at the mid-ocean ridge, creating a rift or crack in the Earth's crust. Magma from the mantle rises to fill this rift, forming a new crust. As the magma cools and solidifies, it creates new oceanic lithosphere.
As the new crust is formed, it pushes the older crust away from the ridge, causing the seafloor to spread apart. This spreading creates a gap or rift valley at the mid-ocean ridge. The process continues as more magma rises and solidifies, pushing the older crust further away from the ridge.
The newly formed oceanic crust is relatively young and less dense than the older crust, so it floats higher on the underlying mantle. This creates a topographic difference between the newly formed crust at the ridge and the older crust further away, forming underwater mountain ranges known as mid-ocean ridges.
Seafloor spreading plays a crucial role in plate tectonics as it is one of the driving forces behind the movement of tectonic plates. It contributes to the continuous renewal and recycling of the Earth's crust, and it is also responsible for the formation of new ocean basins.