Continental crust is made up of less dense materials than oceanic crust and is generally much thicker (generally 25-75km thick as opposed to oceanic 6km). The thickest crust is found underneath the Himalayan mountain chain where the roots of the mountains extend to around 75km. | Continental crust is made up of less dense materials than oceanic crust and is generally much thicker (generally 25-75km thick as opposed to oceanic 6km). The thickest crust is found underneath the Himalayan mountain chain where the roots of the mountains extend to around 75km. |