1. EARTH’S INTERNAL STRUCTURE
1 - Earth structure & dimensions
2 - Layers of the earth
3 - Elements of the earth

2. Earth structure & dimensions
Earth is a terrestrial planet
Terrestrial planet : one of
the first four planets of the
solar system whose surface
is composed of solid rock.
The radius of the Earth is
approximately 6400 km

3. Layers of the earth The Earth is composed of the following layers :
1) The Crust
2) The Mantle
- The upper mantle (or asthenosphere)
- The lower mantle
3) The Core
- The outer core
- The inner core

4. Layers of the earth The Crust Upper Mantle Lower Mantle Outer Core
Inner Core

5. Layers of the earth LAYER DISTANCE TEMP. CRUST 5 – 65 km 5˚ C
UPPER MANTLE
670 km
1000˚ ˚ C
LOWER MANTLE
2885 km
1800˚ ˚ C
OUTER CORE
2270 km
3700˚ ˚ C
INNER CORE
1216 km
+4500˚ C

6. Layers of the earth

7. Layers of the earth: THE CRUST
The solid surface of the Earth is called the crust.
The Terrestrial crust covers the other layers of the Earth.
It becomes warmer and warmer as it approaches the center of the Earth

8. Layers of the earth: THE CRUST
The Earth's crust is solid.
Its thickness varies:
between 5 and 10 km under the oceans
(oceanic crust)
between 30 and 65 km under the continents (continental crust)

9. Layers of the earth: THE MANTLE
THE MANTLE is directly beneath the Earth's crust.
Its temperature is much hotter than the Earth’s crust and is hotter in the lower mantle than the upper mantle (or asthenosphere).
UPPER MANTLE - Asthenosphere
Its thickness can reach 670 km. This layer is semifluid. It consists of partially molten rock. It is believed that this is the surface on which the tectonic plates move (the movement of continents).

10. Layers of the earth: the mantle
LOWER MANTLE
This layer is solid despite its high temperature because the pressure is too strong.
It consists mainly of silicon , oxygen , iron and magnesium.

11. Layers of the earth: the core
THE CORE is located below the two layers of the mantle.
THE OUTER CORE is liquid. The metal elements in this layer gave rise to Earth's magnetic field.
Its thickness is about km .
THE INNER CORE Despite its very high temperature, it is solid due to the pressure.

12. Elements of the earth During the birth of the Earth,
the heavier elements ,
like Iron (Fe) and Nickel (Ni),
were attracted towards the
center of the Earth and
formed the nucleus.
The lighter elements , such
as Silicon (Si) , Oxygen (O)
and Aluminum (Al), have
come together on the surface of the Earth to form
the mantle and crust.

13. EARTH = THE EGG
One can compare the internal structure of the Earth to that of an egg.
The shell is the crust
The White is the mantle
The core is yellow

14. EARTH = THE EGG
CRUST SHELL
MANTLE EGG WHITE
CORE YOKE