Mountains

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Mountains

• How were they built?

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How are mountains built?

• Folding
• Faulting
• Dome building
• Erosion
• Volcanic activity

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• Folding is a process in which the Earth's plates
  are pushed together creating a wavelike
  appearance. Folding bends many layers of rocks
  without breaking them.
• Appalachian Mountains
• Rocky Mountains
• Alps in Europe

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Sideling Mountain, Maryland
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Mountains sometimes form when many layers of the
Earth's crust are moved vertically upward at
fault lines by pressures caused by plates
colliding. Fault lines are great cracks in the
crust. The mountains that are formed in this way
are called fault-block mountains
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Fault-Block Mountains

• Sierra Nevada Mountains in California and Nevada
• Grand Tetons in Wyoming

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Low mountains that were formed when the crust was
heaved upward without folding or faulting into a
rounded dome are called Dome Mountains.
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Domed Mountains

• Black Hills of South Dakota and Wyoming
• Adirondack Mountains of New York

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Mountain-building process known as plate
convergence works as crustal plates move towards
each other.

• Three types of convergence
• Oceanic-Oceanic forms island arcs
• Oceanic-Continental forms volcanic arcs
• Continental-Continental forms non-volcanic
  mountains

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Subduction Zones
Subduction of oceanic crust under continental
crust - volcanic arc
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Volcanic arcs are located along the coastlines of
continents. For instance, the Cascade Range in
the Pacific Northwest and the Andes Mountains of
South America
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Volcanic mountain ranges formed when oceanic
crust collides with continental crust. These are
called volcanic arcs.

• Example
• Cascade Mountains of North America
• Andes Mountains of South America

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Mt. Hood
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Mountains formed from convergence of two
continental plates form non-volcanic mountains
that are located in the interior of continents.
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• Examples
• Rocky Mountains in western U.S and Canada
• Appalachian Mountains in eastern U.S.
• Himalayan Mount ions in Tibet