Glaciers Flashcards
What are the 3 erosional processes in a glacier
Plucking
Freeze-thaw weathering
Abrasion
What is the accumulation zone
Is when there are inputs into the glacial budget
What is the ablation zone
Where thare are outputs from the glacial budgets
Why do glaciersgo down hill
Because of gravity
What is plucking
When meltwater freezes on the rock and when the glacier moves forward it pulls the rocks of the surface
What is abrasion
Rocks being carried by the glacier scrape away at the surface which deepens the glacier
What is freeze-thaw weathering
When water is forced into the cracks in the rock and when the water freezes it expands by 9% which enlargens the cracks and eventually breaks rocks of from the surface
What is the first step of a corrie being formed
Snow builds up in a hollow high above sea level and usually in a north faced dirrection.The snow compacts and turns from snow to fern and eventually to glacial blue ice.Once the glacier reaches the critical depth of 30 meters it becomes a glacier and is pulled down the mountain because of gravity
What is the second step in forming a corrie
Water enters the cracks in the rocks and when it freezes it expands by 9% which enlargens the cracks eventually the rocks are plucked out of the surface and taken with the glacier.
What is the final step in forming a corrie
When the glacier melts a corrie is formed which usually has a lake inside called a tarn but it doesn’t have to have one.
What is a cold environment
It is a area always coverd by ice and it can have glaciers or ice sheets
Are cold environments usually at low or high altitudes
High altitudes because it is much colder at high altitudes
What is a glacial budget
The name of the system of inputs,processes and outputs
What are some featurs of a corrie
They normally have a tarn but they don’t have to.They have a steep back wall aswell.
What is a example of a glacier retreating
The skibidi ohio sigma lost 7 inches