Earths Crust:
The Crust is the first layer that is about 10 miles of rock and loose materials. Scientist call the crust underneath because the crust is almost three times as thick as it is under the ocean. Also, the crust covers most of the mantle and it is the earth's hard outer shell, the surface on which we are living on . However, compared to the other layers the crust is much thinnerbecause It floats upon the softer, denser Mantle. The crust is made up of solid material but this material is not the same everywhere. There is an Oceanic crust and a Continental crust. The first one is about 4-7 miles and 6-11 km thick and mainly covered by heavy rocks, like basalt. On the other hand, the Continental crust is thicker than the Oceanic crust, about 19 miles and 30 km thick. Also, it is mainly made up of light material like granite.