Crust, Mantle, Core (Outer and Inner)

Crust is the thinnest layer. Its thickness varies, for example the crust in ocean or oceanic crust has it thickness of only about ##8## ##km## while in the continental crust it has a depth of up to ##32## ##km##. It is composed of O, Si, Al, Fe, Ca, Na, K, Mg, Ti, and H.

After that, there is a boundary discovered by Andrija Mohorovicic which is named after him. The Mohorovicic Discontinuity or sometimes known as the Moho.

The next one is the mantle which is about ##2900## ##km## in depth. This makes up about ##80 %## of ‘s volume and ##68## ##%## of the its mass. It composed mainly of Si, O, Fe, and Mg.

The core:Outer core which has a depth of ##2250## ##km## is made of liquid Iron and Nickel. It surrounds the Inner core which has a radius of ##1300## ##km##. It is very dense. It is the innermost layer and is made of solid Iron and Nickel.

http://paleogeology.blogspot.com/2008_11_01_paleogeology_archive.html