Earth’s Layers

• Earth formed approximately 4.5 billion years ago. At this time it consisted almost entirely of molten rock (magma).

• Ever since its formation, Earth has been very slowly cooling down.

• As it cooled, Earth differentiated into layers, with more dense material sinking towards the centre and less dense material moving towards the surface.

• During the first few hundred million years after formation, Earth’s surface became solid and water condensed to form oceans.

• Earth consists of four main layers. Starting from the outside, these are:

• The crust

• The mantle

• The outer core

• The inner core

Earth’s main layers are the crust, mantle, outer core and inner core.

(Image: Nouval, Adobe Stock)

• Each of Earth’s layers has distinct physical and chemical properties.

• Temperature, pressure and density all increase with depth below Earth’s surface.

• While temperature and pressure increase gradually, there are distinct density differences between Earth’s major layers.

Temperature, pressure and density all increase with depth below Earth’s surface.

(Sources: Karla Panchuk, Wikipedia Commons; Anita Zeidler, ResearchGate; Robert Tenzer, ResearchGate)