top of page

The Earth's Inner and Outer Structure

To better understand the Earth, geographers distinguish among the Inner and the Outer Structure. 

​

The Inner Structure of the Earth refers to the different layers that compose the planet: inner core, outer core, matnle and crust. 

​

The Outer Structure refers to the spheres that interact on the surface of the Earth, on the crust, creating the landscapes and living conditions that surround us: lithosphere, hydrosphere, biosphere and atmosphere. 

The Inner Structure of the Earth

The Earth has four layers:

​

  • The crust: solid outer part of the Earth’s surface. It represents around a 1% of the Earth. Temperature: around 22ºC. State: Solid. Composition: Minerals and metals. 

  • The mantle:  located under the crust. It represents 84% of the Earth. It is formed by some solid materials but mainly by melted rocks that forms the magma. Temperature: 1.400ºC - 3.000ºC. State: Liquid and solid. Composition: iron, oxygen, silicon, magnesium and aluminium.

  • The core: the inner part of the Earth. It represents 15% of the Earth. It has two parts:

    • The inner core which is extremely hot but solid as its materials are under high pressure. Temperature: 5.000-6000º C. State: solid. Composition: iron and nickel

    • The outer core which is also very hot but formed by melted materials. Temperature: 4.000-6.000º C. State: liquid. Composition: iron, nickel, sulphur and oxygen.

The Outer Structure of the Earth

Our living conditions arise from the combination of different elements. To better understand them, geographe organize them into four interconnected spheres. 

​

  • Lithosphere/Geosphere

  • Hydrosphere

  • Biosphere

  • Atmosphere

bottom of page