What
are fold mountains?
Fold mountains
are mountains formed from the folding of the earth's crust.
How
are fold mountains formed?
Fold
mountains are formed when two plates move together (a compressional
plate margin). This can be where two continental plates move towards
each other or a continental and an oceanic plate. The movement
of the two plates forces sedimentary rocks upwards into a series
of folds. Fold mountains are usually formed from sedimentary rocks
and are usually found along the edges continents. This is because
the thickest deposits of sedimentary rock generally accumulate
along the edges of continents. When
plates and the continents riding on them collide, the accumulated
layers of rock crumple and fold like a tablecloth that is pushed
across a table.
There are
two types of fold mountains: young fold mountains (10 to 25 million
years of age, e.g. Rockies and Himalayas) and old fold mountains
(over 200 million years of age, e.g. Urals and Appalachians of
the USA).
Human
activity in fold mountains - The Alps
The Alps are
home to eleven million people and thus the most densely populated
mountain area in the world. The economy of this region is based
on the exploitation of the coniferous forest and pasturing dairy
cattle, and tourism plays an important role.
Tourism
Since the
end of the second world war The Alps have become the winter and
summer play ground of European urban dwellers.
Winter
The Alps are a very popular destination
amongst winter tourists. Ski resorts such as Val d'Isere and Les
Deux Alps have been purpose-built. These areas are very crowded
in the winter but tend to be quieter in the summer. However, traditional
ski resorts tend to be busy throughout the year.
Summer
Between June and September
The Alps is heavily populated with walkers, cable-car riders and
paragliders.
The
huge number of tourist visitors to The Alps has led to them becoming
the most threatened mountain chain in the world. This is in terms
of its fragile ecological and physical system.
Farming
and Forestry
Coniferous
trees are the main trees forested in the Alps. They are ideally
suited to the Alpine environment. Their conical shape makes the
tree stable in windy conditions. The downward sloping, springy
branches allows the snow to slide of the tree without damaging
its branches.
The wide
meadows of The Alps make the area ideal for sheep farming. In
the more extreme upland areas goat herding is the main type of
farming. The cold climate and difficult relief make it almost
impossible for arable farming to occur.
HEP
Schemes
Hydroelectric
power schemes are common in The Alps. The combination of tectonic
and glacial processes make the area ideally suited for HEP schemes.
HEP schemes often involve many different watersheds. It is an
area of excess water and deep U-shaped valleys. Since the development
of HEP at the end of the 19th and the beginning of the 20th centuries
these valleys have been dammed and used to develop HEP.
The development
of HEP in The Alps led to the establishment in the lower valleys
of electricity-dependent industries, manufacturing such products
as aluminium, chemicals, and speciality steels.
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