The Crust
The crust, or Lithosphere, is the thinnest layer and the layer on which we live. It it only between 3 and 62 miles thick. The temperature increases with depth, but never reaches higher than 2372 degrees Fahrenheit. The temperature of the surface of the crust changes with the air temperature. Like the mantle, it is made of the stone peridotite. Unlike the mantle, the peridotite is in a completely solid state.
The crust is not one piece, but many different pieces that fit together, called Lithospheric Plates. Through the movement of the mantle, the plates shift and slide over, under, and past each other. These movements cause earthquakes, tsunamis, and other geological processes.
There are two types of Lithospheric Plates, the continental plates, which are thicker, and the oceanic plates, which are thinner. The continental crust lies under the land and is made up of mostly granite rock, while the oceanic crust lies under the ocean and is made up of Basalt rock.
