Weathering in glacial environments Flashcards
What is weathering?
Weathering is a sub-areal process, that involves the breaking down of rock by the action of weather, plants or chemical action. It happens in situ, that is ‘without movement.’
Weathering is a sub-areal process, what does this mean?
Sub-areal process - A land-based process which alters the shape of the land through a combination of both weathering and mass movement.
What is the key distinction between weathering and erosion?
The key distinction between weathering and erosion is that weathering prepares material for subsequent removal by erosion.
What is the impact of physical weathering?
Physical (or mechanical) weathering causes the disintegration of exposed rock, without any change in its chemical composition.
What is the impact of chemical weathering?
Chemical weathering causes exposed rock to undergo chemical decomposition, changing the chemical and mineralogical composition of the rock.
What is the consequence of the weathering system?
The consequence of the weathering system is the production of smaller, less resistant materials that differ physically and chemically from the original parent rock.
What happens to the resistance level of rock particles as they disintegrate and reduce in size?
As the disintegrate and reduce in size, the resistance of rock particles falls to a level at which point the system energy available is now sufficient to erode and transport them.
What may also be produced as a consequence of the weathering system?
Soluble substances may also be produced which are readily removed by meltwater.
How does weathering impact the glacial landscape system?
Materials are released from storage in the lithosphere to become an input into the glacial landscape system.
Give an example of a particular type of physical weathering that the low temperatures of glacial environments promote?
Freeze-thaw weathering
Give an example of chemical weathering that occurs in glacial environments?
Chemical weathering occurs in glacial environments, particularly carbonation. This is because carbon dioxide is more soluble in water at lower temperatures.
Describe the extent of biological weathering in glacial environments?
There is usually only limited biological weathering caused by plant and animal activity due to the climatic limiting factors which have resulted in low ecosystem productivity.
