The MantleIf the earth would be compared to an egg, the mantle would be the white of the egg: the middle and thickest layer. The mantle is about 2900km thick. It's temperature ranges from 1000°C to 4000°C ("The
Mantle." 2013). The mantle is composed of very hot and very dense rock . There is iron (Fe), magnesium (Mg), oxygen (O), silicon (Si) and many other materials in it ("The
Mantle." 2013). The mantle is semi-solid: it is more solid ad the top and gets more liquid near the core.
The mantle is separated into two parts: the upper mantle and the lower mantle. A difference between the two mantles is that the upper mantle is a lot thinner than the lower mantle. another difference is that the temperature of the upper mantle is lower than the lower mantle's ("The Earth's Interior." 2013). |
The CrustThe crust is the closest solid sphere to humans, and it is the surface of the earth. It is very thin compared to the mantle and the core. The earth is a little like an egg. if you think of the earth as an egg, the crust would be the shell, and like the shell of an egg, the crust is very brittle (hard but easy to break). The temperature of the crust can vary from surface temperature to about 820°C ("Earth's
Layers: The Crust."
2013).
The crust is separated into two categories: the oceanic crust and the continental crust. The oceanic crust is the crust beneath the oceans and it is very thin, about 7km thick ("The Earth's Interior." 2013). The crust is thinner under the oceans because of the water pressure. It is made out of relatively dense rock, like basalt ("Earth's Layers: The Crust."2013). The continental crust is the the land. This crust is much thicker than the oceanic crust and it is on average 33km thick although it can go up to 50km thick in certain places ("The Earth's Interior." 2013). This crust is composed of relatively light rocks like granite. |