Paragraph on “Earth’s Crust and Inner Core” complete paragraph for Class 9, Class 10, Class 11 and Class 12

Earth’s Crust and Inner Core

Millions of years after it’s origin, the Earth still has a molten core, about 2600 km thick, with a temperature in the range of 4,700° centigrade. Above this inner core is an outer core which is about 2,000 kms thick and is made up of molten iron with temperatures in the range of 2,2000 centigrade. The ‘Mantle’, as it is called, which surrounds both the inner and the outer core is about 2,800 km thick. The temperatures in this layer are also very high but it is sheer pressure which keeps the rocks in this layer solid and prevents them from becoming molten. Uppermost on the surface is the Earth’s ‘Crust’ which is uneven and has thicknesses ranging from about 75 kms below the land we live on to about 5 km under the deepest oceans. About 71% of the Earth’s crust is covered by the oceans and about 29% of it is above the water level.