A diagram showing the interior of the earth is given ahead :
From the diagram it will be noticed that density goes on increasing towards the interior of the earth. Three main divisions of the interior of the earth are crust, mantle and core. Each of these three divisions has upper and lower part. Like density, temperature and pressure increase with the increase in depth inside the earth.
Crust: The thickness of the crust is 4-7 km below the seafloor and about 35 km below the continents. Beneath the mountain, the crust is 70 km thick. Continents are however made of a lighter material and rise above the oceanic crust.
Mantle: It extends upto 2900 km. The upper part is only about 100 km thick forming part of the lithosphere. The lower Mental is in a semi-plastic state.
Core: It has a radius of 3470 km and its upper part is in a liquid state and the lower part has enormous heat and is highly compressed, therefore at a solid rate. Iron and nickel are said to be the constituents of the Inner Core.
