Holly and jazz say please help because we have a crazy oceanography teacher

Well... have you ever seen or heard of a centrifuge? It spins liquids so they separate into layers. I think the theory is the same thing... when the earth was formed it was a big ball of hot molten rock.. as it spins the layers separate... as each layer cools it forms to a solid. The outside crust etc layers insulate the center keeping it in its liquid magma form.

Hope that helps!

The earth before it was earth, was another planet. An asteroid or other body collided with the earth and broke it into many other pieces, over millions, maybe even billions of years, the pieces came back together through gravitaional force to form the earth and the moon. This also explains why the earth has so many different plates that are still moving. The asteroid that caused all of this is now in an oval shaped orbit around the sun and is coming back in 2012 to pass near the earth. This will cause catastrophic problems with the planet.

The earth before it was earth, was another planet. An asteroid or other body collided with the earth and broke it into many other pieces, over millions, maybe even billions of years, the pieces came back together through gravitaional force to form the earth and the moon. This also explains why the earth has so many different plates that are still moving. The asteroid that caused all of this is now in an oval shaped orbit around the sun and is coming back in 2012 to pass near the earth. This will cause catastrophic problems with the planet.