Why are the mid-ocean ridges higher in elevation than the surrounding ocean floor?

Question

Quizplus · Accepted Answer

Mid-ocean ridges are higher in elevation than the surrounding ocean floor because the warmer material near the ridge is less dense, so it is more buoyant on the mantle. The elevated ridges are formed as magma rises from deep within the Earth's mantle and solidifies. The magma creates new crust that pushes the older, colder oceanic crust away from the ridge. As the new crust moves away from the ridge, it cools and sinks, creating the surrounding lower elevation ocean floor.

Why Are the Mid-Ocean Ridges Higher in Elevation Than the Surrounding