Because towards the center of the earth, there is more mass on top of it, so there is more pressure. All of the other layers, and the stuff on top of the earth is pushing down on it from all sides. For the mantle, its only the stuff on the top of the earth that is putting pressure on it.
85 percent
mantle
The mantle
The degree of temperature and exertion of pressure by the molten materials (magma) within the mantle is directly proportional to its depth. This means that, the deeper you go down the mantle the higher the degree of temperature and pressure exerted.
I'm thinking center to equator
The pressure from the outer core, mantle, and crust sqeeze it to a solid although is is fiery hot.
the mantle
The pressure increases as you go deeper. The deeper you go the greater the pressure
The pressure increases as you go deeper. The deeper you go the greater the pressure
The Earth's mantle.
The mantle is the solid layer of earth that can flow because of great heat and pressure
the core
85 percent
mantle
the mantle
The mantle
The mantle is closer to the molten core of earth, so it is constantly heated by it. The crust is exposed to the atmosphere, which has some cooling effect, and the crust is, of course farthest from the core.