Explain how plate movement over the past 250 million years has created the present configuration of the oceans and explain in terms of rock types why the continents rise up further than the ocean floors.

The main mechanism that is behind the configuration of the present landscape and the formation of oceans is the plate tectonic movement, which is continuously taking place since the last 250 million years. This plate movement is going on due to the generation of large uprising current in the mantle, which is commonly known as the convection current. These currents are originated due to the heat radiated from the extreme interior of the earth.

Due to this motion of plates, there formed three different types tectonic boundaries such as the convergent, transform and divergent boundary. The high elevated mountains are formed adjacent to the convergent plate boundaries and the divergent plate boundaries are responsible for the formation of ocean bodies.

The continents are generally comprised of continental crust, which is comprised less denser minerals and rocks, and on the other hand, the oceans are comprised of oceanic crust which are made up of heavier minerals and rocks. It is because of this reason, the continents floats and it rises up during the collision of any two plates namely continent-continent, continent-ocean or oceanic-oceanic plate collision.