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Fold Mountains
Mountains formed when two
Plates Collide.
Fold Mountains
• Fold mountains are mountains that are
made when two of the earth’s plates
collide.
• When two plates collide the pressure
compresses the rocks, forcing them to
buckle and fold. Think of what happens to
the bonnet of a car during a crash.
Fold Mountains
Fold Mountains
Evidence of Folding
• Scientists have found fossils of dead sea
creatures thousands of metres up in the Andes
in South America.
• These creatures lived in the sea, and their
remains sank to the ocean floor when they died.
• Their remains were trapped in newly forming
rocks which are later pushed up from under the
sea when plates collide to make fold mountains.
Ridge and Valley Landscape
• When the two plates collide the crust
buckles and folds. This creates a pattern
of ridges and valleys.
• The downward part (the valley) is called a
syncline.
• The upward part (the ridge) is called an
anticline.
Fold Mountains
1.Alpine fold Mountains – youngest, formed
30-35 million years ago. E.g. Rockies
(America), Alps (France), Himalayas (Asia).
2.Armorican fold Mountains – formed 250
million years ago. E.g. Magillicuddy Reeks
(Kerry). ‘Munster fold Mountains’.
3.Caledonian fold Mountains – oldest,
formed 400 million years ago. E.g. Wicklow
Mountains.
Ireland’s Munster Mountains
• When the African plate collided with the
Eurasian plate 250 million years ago, there
was a ripple effect.
• The force of the impact reached southern
Ireland and resulted in the formation of
mountains such as Ireland’s tallest
mountains, The Macgillycuddy Reeks and
the Comeragh Mountains.