mountain building. the himalayas harz mountains in germany
TRANSCRIPT
So what exactly are the processes that take So what exactly are the processes that take place to form these mountains?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 dome-shaped cooled magma of harder rock
For a more
holistic view of
mountains…
So what exactly are the processes that take So what exactly are the processes that take place to form these mountains?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
For a more
holistic view of
mountains…
So what exactly are the processes that take So what exactly are the processes that take place to form these mountains?place to form these mountains?
• Volcanic mountains– Self-explanatory!– More details in the future lessons!
Mountain BuildingMountain 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 Stage 2: Rock Deformation and Crustal UpliftCrustal 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 Stage 3: Crustal Uplift caused by Isostatic Rebound and Block-Faulting Isostatic Rebound and Block-Faulting
http://www.physicalgeography.net/fundamentals/10k.html
Stage 3: Crustal Uplift caused by Stage 3: Crustal Uplift caused by Isostatic Rebound and Block-Faulting 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
• Normal (tensional)• Reverse (compressional)• Graben (tensional, subsidence)• Horst (compressional, uplift)• Transform
• What landform does faulting remind you of?