User:Sthembisowi/sandbox

The internal structure of the earth is made up of mainly four concentric and spherical layers. From the inner most they are core, mantle and crust. These layers differ by the size and composition that they are made up of. The crust makes up approximately 2 percent of earth by mass. It is made up of felsic rocks. The mantle makes up about 68 percent of Earth’s mass. It is hot but solid. The core is mostly iron metal. It makes up about 30 percent of the Earth's mass. Lithosphere and asthenosphere are divisions based on mechanical properties. The lithosphere is composed of both the crust and the portion of the upper mantle. The asthenosphere is partially molten upper mantle material that behaves plastically and can flow.