Mountain Types Outline 1) Describe the 2 mountain belts and where

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Mountain Types Outline
1) Describe the 2 mountain belts and where they are located
a) Circum-pacific
 Forms a ring around the Pacific Ocean
 A large mountain system
b) Eurasian Melanesian
 Runs from the Pacific Islands through Asia and southern Europe into
North-western Africa
2) Explain 3 ways that mountains can be formed.
a) Continental-oceanic convergence
 Oceanic lithosphere subducts
 Produces large scale deformations that produces uplifted mountains
 Partial melting of overlying mantle and crust and produces magma that
may erupt and form volcanic mountains
b) Oceanic-oceanic convergence
 The denser oceanic plate subducts beneath other plate
 Volcanic mountains form
 Fluids from the subducting lithosphere cause partial melting of overlying
mantle and crust
 Resulting magma rises and breaks through the oceanic lithosphere
 Eruptions form island arcs
c) Continental- Continental Convergence
 When two continental plates collide, neither subducts and instead lifts
upward
 Forms mountains and plateaus on the sides of it
3) Describe the 4 types of mountains
a) Folded Mountains
 A mountain that forms when rock layers are squeezed together and uplift
 Highest mountain ranges in the world
 Same stress that forms plateaus
b) Fault- Block
 A mountain that forms when faults break Earth’s crust into large blocks
and some blocks to tilt and to drop down relative to other blocks
 Parts of Earth that have been stretched and broken into large blocks,
faulting may cause the blocks to tilt and drop relative to other blocks
 Same type of faulting also forms grabens
 Grabens, fault block mountains commonly occur near each other
c) Dome Mountains
 A circular fracture in which stratified rock slopes downward gently from
the central point of folding
 Rare, and form when magma rises through crust and pushes the rock
layers above the magma
 Volcano that never erupted
d) Volcanic mountains
 Mountains that form when magma erupts onto Earth’s surface
 Commonly form along convergent plate boundaries
 Some of the largest volcanic mountains part of mid ocean ridge along
divergent plate boundaries
 Others form on hot spots
4) Relationship Between Grabens and Plateaus
a) Plateaus
 Same stress that forms folded mountains
 A large, flat areas of rock high above sea level
 Form when thick layers of rock are slowly uplifted so that the layers
remain flat instead of faulting and folding
 Located near mountain ranges
 Plateaus can form when layers of molten rock harden and pile up on
Earth’s surface or when large areas of rock are eroded
b) Grabens
 Same type of faulting as fault- block mountains
 Develop when steep faults break the crust into blocks and one block slips
downward relative to the other block
 Commonly occurs near near fault-lock mountains
5) Mountain types, grabens and plateaus
a) Folded Mountains-Appalachian Mountains: from Georgia to Canada
b) Plateaus- The Colorado Plateau: near the Rockies
c) Fault-Block Mountains- The Sierra Nevada Range: California
d) Graben- Death Valley: Between 2 mountain chains in California
e) Dome Mountain- the Adirondack Mountains: New York
f) Volcanic mountains- Mount Saint Helens: Washington
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