The process by which the earth is divided up into layers with different densities is called what?
1 Answer
This is called differentiation.
Explanation:
It's easy to see differentiation at home. Just pour some oil and some water together into a vessel and see what happens. The liquids do not mix, instead the less dense oil floats on top of the more dense water. Earth's gravity has differentiated your liquids.
So why does this not work with steel balls and pebbles? The steel balls are more dense, but because you are dealing with solid matter you don't get flow as easily as you do with oil and water.
To make the rock and iron of the Earth flow and thus differentiate like your oil and water, you need much stronger gravitational forces to generate the necessary heat and pressure. Earth's gravity acting on your tabletop can't do it. But Earth's gravity acting over a much greater distance and with a lot more mass, in the planet as a whole, can do so. That is how the Earth differentiates its rockyvand iron-uch layers while your tabletop experiment with pebbles and steel balls can't.
Generally, anything whose gravity can make it round likely has enough gravity to differentiate it. Besides the Earth we can see it in the Moon, which has a small iron core, and in various planets and dwarf planets.
