Transcript How are mountains formed? - Crossdale Drive Primary School

How are mountains
formed?
- To be able to explain how mountains
are formed
Plate Tectonics
The Earth's surface is made up of a series of
large plates (like pieces of a giant jigsaw puzzle)
called tectonic plates.
These plates are in constant motion travelling at
a few centimetres per year. This is called
continental drift.
They move because a plume of magma is rising deep within
the earth’s mantle (the outer layer of the earth)
As it moves, pressure builds up which forces the plates to
move.
As they move against each other, they cause are sites of
intense geologic activity, such as earthquakes, volcanoes, and
mountain building.
How are Folded Mountains formed?
Examples of Folded Mountains:
• Himalayan Mountains in Asia
• The Alps in Europe
•T he Andes in South America
• The Rockies in North America
This is a convergent plate boundary.
They form Folded Mountains when the
two plates move towards each other and
collide head on.
They are formed over millions of years,
as the plates continue to push up and
create the folds
What happens when you fold a piece of Paper?
http://videos.howstuffworks.c
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How are Fault Block Mountains formed?
Cracks in the earths crust (faults)
Either side of the fold tries to move in opposite
directions but they are locked together
They will not move until enough pressure
builds up.
When this happens they slide past each
other releasing energy.
How are Volcanic Mountains Formed?
For example: Mount St. Helens in North America
Formed when a plate carrying the Ocean basin (the heavier plate),
dives below the plate carrying the continent. The pressure builds up.