Earth's Structure
Earth has four layers: the solid inner core, liquid outer core, thick mantle and thin outer crust.
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Earth has four layers: the solid inner core, liquid outer core, thick mantle and thin outer crust.
- The core is mostly iron and nickel
- The mantle flows very slowly
- The crust is broken into plates
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Earth's Structure?
Within Geography, which covers maps, landforms, weather, climate, population and settlements: understand how our planet and people connect, this topic explains Earth's Structure. Geography explains how places, people and natural processes connect, so each topic here combines a clear definition with a visual model.
Check that you can explain Earth's Structure in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Earth's Structure helps you explain patterns on maps and in the news, and make reasoned decisions about places and environments.
Earth's Structure in detail
The Earth has four main layers. The thin, solid crust is 5–70 km thick, with thinner dense oceanic crust and thicker lighter continental crust. Below is the mantle, about 2,900 km thick, of hot, semi-molten rock that flows very slowly.
The outer core is liquid iron and nickel, and the inner core is solid iron and nickel, with temperatures up to 5,500 °C. Convection currents in the mantle move the tectonic plates. Movement in the outer core generates Earth's magnetic field. We learn about the interior from seismic waves, since no one has drilled through the crust.
How the interactive helps you understand Earth's Structure
Watch the tectonic plates in the interactive. Use any sliders or buttons it offers to change the values and see how the tectonic plates responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Earth's Structure.
Real-life uses and examples
- Support an answer about Earth's Structure with a named case study and specific evidence.
- Interpret a graph or map that shows Earth's Structure and say what it suggests.
- Describe a real place where Earth's Structure can be seen, using a map or photograph.
Common mistakes to avoid
- Writing general statements without a named place or example.
- Mixing up cause, effect and consequence when you explain Earth's Structure.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Earth's Structure
What is Earth's Structure?
Earth has four layers: the solid inner core, liquid outer core, thick mantle and thin outer crust.
What are the most important points about Earth's Structure?
The main points are: The core is mostly iron and nickel; The mantle flows very slowly; The crust is broken into plates.
Why is Earth's Structure useful?
Understanding Earth's Structure helps you explain patterns on maps and in the news, and make reasoned decisions about places and environments.
How can I practise Earth's Structure?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Earth's Structure?
Related topics in Geography include Volcanoes, Fold Mountains, Erosion and Deposition.