4) The sea floor spreads at the mid-ocean ridges. As the spreading increases, numerous changes start to occur on the seafloor, both at the mid-ocean ridge and further away from it.
The mid-ocean ridge itself starts off as a small underwater hill from which magma comes out. As the spreading continues, and more and more magma is pushing through, the mid-ocean ridge rises gradually and it becomes an underwater mountain range. As the mid-ocean ridge gains in height, it also becomes more and more steep.
The ocean floor that is further away from the mid-ocean ridge, on the other hand, is experiencing the opposite. The water is flattens the sea floor with its power, so far away from the mid-ocean ridge, where there isn't any constructive forces in action, the destructive dominate, so the ocean floor is becoming deeper and deeper.
5) The physical processes that cause the formation of the mid-ocean ridges have their origin in the mantle layer. The mantle layer has mantle plumes at some places below the crust. The mantle plumes have higher temperatures and pressure than the rest of the upper mantle, and they manage to push magma through the crust and crack it open.
When the crust is cracked by the mantle plumes, there is lot of volcanic activity occurring, be it on land or in the seafloor. This creates crack in a plate, and if the crack is big enough, it actually manages to split a tectonic plate in two parts.
The mid-ocean ridge is the physical feature that forms on this places (in the ocean), and it represents a very long, very active volcanic, underwater mountain range. The reason why the data is showing the trends about this is that it is very important to understand this process, as it manages to cause lot of changes, both short term and long term ones, some of which can also cause lot of problems.
6. If we take the ocean floor, we can see that there are differences in its temperature, density, and age in different parts of it. The mid-ocean ridges are situated around the central part of the oceans, and they are the places where new crust is formed, while the oceans get subducted on their ages when they collide with continental plates.
The crust in the ocean tends to be the youngest at the mid-ocean ridge itself, as this is the place where the crust is forming. The further away you go from the mid-ocean ridge, the older the crust becomes.
The density tends to be lower at the mid-ocean ridge, as the magma has lower density than the rocks. So the further away the place is from the mid-ocean ridge, the higher the density, and the closer it is, the lower the density.
The temperature of the oceanic crust is the highest at the mid-ocean ridge as it has active volcanism. The temperature gradually decreases as the distance from the mid-ocean ridge increases, as there is no direct heating source on the oceanic crust.
