unit 3 the outer layer of the earth

UNIT 3THE EARTH RELIEF

THE OUTER LAYER OF THE EARTH

THE EARTH´S CRUST

• The Earth´s crust is thicker in some places, forming the continents. In other places, where is thinner, it lies below the oceans

• It is not flat and smooth• On land and under the oceans there are mountains,

valleys, basin and plains. These features form the Earth relief.

• Mount Everest is the highest point on Earth (8848 m.)• The Mariana Trench is the lowest point (11022 m.

beneath the Pacific Ocean)

The Himalayan Range

Deepest Spot of the Planet

Internal and external forces cause the earth´s relief which is always changing

Internal forces• The pressure from molten

materials in the Earth´s mantle can cause the crust to crack. If this happens, large pieces of the crust can rise above the surface, or sink below it

• Volcanoes, earthquakes and mountains are the result of internal forces

External forces• Water• Wind• Vegatation• Human action

QUIZ

1. What sections can the Earth be divided into?

2. Why are some parts of the Earth above the water and other parts below it?

3. What internal and external forces change the Earth´s relief

SOLUTIONS

1. The Earth is made up of three layers: the internal core, thee external core, and thee mantle and crust

2. In some areas the Earth´s crust is thik and it forms continental land masses, and in others is thinner and forms ocean floors

3. The internal forces that change the Earth´s relief are the pressures from the molten materials in the Earth´s mantle. The external forces are water, wind, vegetation and human activity.