Inside Our Earth (Basic)

Interior Of The Earth

The Earth’s interior is divided into three main layers:

Crust: It is the outermost and thinnest layer of the Earth. It is divided into two types:
- Continental Crust – thicker and made up mostly of granite.
- Oceanic Crust – thinner and made up mostly of basalt.
Mantle: Located beneath the crust, it extends to about 2,900 km. It is made of semi-solid silicate rocks rich in iron and magnesium.
Core: The innermost layer, composed mostly of iron and nickel. It is divided into:
- Outer Core – liquid in nature.
- Inner Core – solid due to immense pressure.

These layers differ in composition, temperature, and physical state, with temperature and pressure increasing as we go deeper.

Rocks And Minerals

Rocks are the natural masses of mineral matter that make up the Earth’s crust. They are classified into three main types:

Igneous Rocks: Formed from cooling and solidification of molten magma. Examples: granite, basalt.
Sedimentary Rocks: Formed by the accumulation and compaction of sediments. Examples: sandstone, limestone.
Metamorphic Rocks: Formed when existing rocks are subjected to heat and pressure. Examples: marble (from limestone), slate (from shale).

Minerals are naturally occurring substances with definite chemical compositions and physical properties. They are the building blocks of rocks. Examples: quartz, mica, feldspar.