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1. Internal geological processes
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Key concepts
❚❚
The relief of the continents and
oceans has different features.
❚❚
Relief is continually subject to
both gradual and sudden
changes.
1.1.
Evolution of relief
The age of the Earth is measured in millions of years. During this time, there have
been continuous and enormous changes in the relief, the position of the continents
and oceans, and the climate and vegetation. The most significant changes are those
that affect the size and the position of the continents. They changed from being
almost non-existent to occupying almost a third of the Earth’s surface.
150 million years ago (Jurassic period)
500 million years ago (Cambrian period)
Reconstruction of the Earth at different moments in the past
Understand
7.
Look at the three photos above. Listen and say which process is
described.
8.
Explain in your ownwords the difference between the terms landscape
and relief.
9.
What would the landscape around you be like without human action?
10.
Give at least two examples of gradual and sudden processes that
change the relief.
Analyse
11.
Discuss what the Earth will look like in one hundred thousand years.
Do you think it will be the same as now? Explain your answer and give
specific examples.
Volcanic eruption
Cliffs
Dunes
The landscape, especially the vegetation, is very vulnerable to human action. Fires,
cutting down trees, urbanisation of land and construction of communication links
quickly transform the landscape, especially in more densely populated areas. The relief
that surrounds us looks solid and unalterable
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but it also changes. There are very slow
processes that are unnoticeable in a person’s lifetime, such as the erosion of amountain
or the movement of the continents. Other processes are sudden and violent and cause
big changes in a short period of time, such as volcanic eruptions or earthquakes.
2
unalterable
:
impossible to change
