Structure of the Earth

 

Structure of the Earth

 

Structure of the Earth – Cross Section Diagram

 

 

• The Earth is a sphere-shaped planet with three layers inside.
  
  
• The layers are:
• the crust (rocky)
• the mantle (soft)
• the core (metal).
  
  
• The core has two parts: the inner core (solid) and the outer core (liquid)

 

Elements in the Earth

Human activities use a wide range of elements, including:

• Hydrogen (H) and oxygen (O) found in water
• Iron (Fe) used for building materials and in car bodies

 

All these elements can be found in the crust, the atmosphere and the oceans, which all form part of the Earth’s structure. We can use some of these things for our daily life, but we have to be careful not to use them all up.

 

The Crust

The top layer is the crust. It is like a big puzzle of land pieces called plates. The plates move slowly because the layer below them is soft and flows. The crust has many rocks that have different things in them, like oxygen, silicon, iron, and aluminium.

 

 

 

The Mantle

The middle layer is the mantle. It is thick and soft like a liquid. We cannot get anything from the mantle because it is too deep and hot.

 

 

The Core

The bottom layer is the core. It is made of metal, mostly iron and nickel. The core has two parts: the inside part is hard and the outside part is liquid. The core makes the Earth magnetic, which means it has a north and a south pole. We cannot reach the core because it is too deep and hot.

 

🌍 Knowledge Check: Structure of the Earth

Test your knowledge on the layers of our planet and the atmosphere based on the lesson content.

1. Which layer of the Earth is described as being semi-solid and able to flow very slowly?

• The Inner Core
• The Mantle
• The Crust

2. What is the approximate percentage of Oxygen in the Earth's atmosphere?

• 78%
• 21%
• 0.04%

3. Why is the Inner Core solid even though it is the hottest part of the Earth?

• Because it is made of ice.
• Because it is cooled by the mantle.
• Because of the extreme pressure at the centre of the Earth.

4. Which two metals primarily make up the Earth's core?

• Iron and Nickel
• Gold and Copper
• Aluminium and Magnesium

5. How thick is the Earth's crust beneath the continents?

• Around 5km
• Up to 70km
• Over 2,900km

Click to Reveal Answers

1. The Mantle (It is a thick layer of semi-solid rock).
2. 21% (Nitrogen is 78%, Oxygen is 21%).
3. Extreme pressure (High pressure keeps the inner core solid despite high temperatures).
4. Iron and Nickel (The core is made of these dense metals).
5. Up to 70km (Oceanic crust is thinner at 5km, continental crust is thicker).

 

Summary:

 

• The Earth has three layers: the core (metal), the mantle (rock), and the crust (hard).
• Different parts of the Earth have different things in them, like iron, nickel, and oxygen.
• The crust is broken into big pieces called plates that move slowly because of the mantle underneath.