UNIT 3 THE EARTH RELIEFTHE 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)
Internal and external forces cause theearth´s relief which is always changingInternal forces External forces• The pressure from molten • Water materials in the Earth´s • Wind mantle can cause the crust • Vegatation to crack. If this happens, • Human action large pieces of the crust can rise above the surface, or sink below it• Volcanoes, earthquakes and mountains are the result of internal forces
QUIZ1. 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
SOLUTIONS1. The Earth is made up of three layers: the internal core, thee external core, and thee mantle and crust2. In some areas the Earth´s crust is thik and it forms continental land masses, and in others is thinner and forms ocean floors3. 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.