Transcript Mountain Building

Mountain Building
The Himalayas
Harz Mountains in Germany
Mount Pinatubo
Rocky Mountains
Sierra Nevada
Catskills of New York
Black Hills of South Dakota
Mauna Kea
Guess the types of mountains…
So what exactly are the processes that take
place to form these mountains?
• Dome mountains
– Magma pushes up but doesn't actually crack through
the surface, you can get a dome mountain
– Without erupting onto the surface, magma pushes up
overlaying rock layers
– Cools and forms hardened rock as source moves
away
– Uplifted area created by rising magma is called a
dome
– Over long periods of time, erosion wipes away the
outer layers of the mountain, exposing the domeshaped cooled magma of harder rock
So what exactly are the processes that take
place to form these mountains?
• Plateau mountains
– Large flat areas pushed above sea level by
forces within the Earth or formed by layers of
lava
– Plateau mountains are often found near
folded mountains
– As years pass, streams and rivers erode
valleys through the plateau
So what exactly are the processes that take
place to form these mountains?
• Volcanic mountains
– Self-explanatory!
– More details in the future lessons!
Mountain Building
•
3 stages
(1) accumulation of sediments
(2) rock deformation and crustal uplift
(3) a period of crustal uplift caused by isostatic
rebound and block-faulting
Stage 2: Rock Deformation and
Crustal Uplift
• Fold mountains
– Fold mountains are
formed when two
plates collide head on
– Edges of each tectonic
plate crumple and
buckle
– Monocline, syncline,
anticline,
http://www.physicalgeography.net/fundamentals/10k.html
Stage 3: Crustal Uplift caused by
Isostatic Rebound and Block-Faulting
http://www.physicalgeography.net/fundamentals/10k.html
Stage 3: Crustal Uplift caused by
Isostatic Rebound and Block-Faulting
• Fault-block mountains
– Faults named according to type of stress that acting
on rock and nature of the movement of the rock
blocks either side of the fault plane
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Normal (tensional)
Reverse (compressional)
Graben (tensional, subsidence)
Horst (compressional, uplift)
Transform
• What landform does faulting remind you of?