1. Lithosphere
2. Mantle
3. Hydrosphere
4. Atmosphere
Lets discuss them one after the other.
1. Lithosphere; this comprises two distinct parts, The upper and the lower.
The Upper part mainly of granite rocks forming the continent. The mineral constituents are silica and Aluminium. It is therefore, called SIAL
The Lower part mainly of basaltic rocks forming the oceans floors. It is made up of silica, iron and magnesium.It is called SIMA.
2. Mantle; This composed mainly of dense rocks rich in olivine. The interior layer is the barysphere.
3. Hydrosphere; This is the part of the earth's crust which is submerged by oceans and seas. It extend sky-wards for over fifteen miles into what is known as atmosphere.
4. Atmosphere; This is a mass of gases in the sky. The percentage of the different gases in the atmosphere are as follows-
i. Nitrogen - 78%
ii. Oxygen - 21%
iii. Rare gases - 1%
This is all what the earth's structure consists.
