AEOLIAN EROSION
QUESTION:
What is the name given to erosion caused by wind removing and reshaping sediment?
ANSWER:
Aeolian erosion.
QUESTION:
Which type of aeolian transportation carries very fine dust high in the atmosphere?
ANSWER:
Suspension.
QUESTION:
What landform is commonly produced when deflation removes fine particles and leaves larger stones behind?
ANSWER:
Desert pavement.
QUESTION:
Why are aeolian processes particularly effective in deserts?
ANSWER:
Deserts have dry, loose and exposed sediment with little vegetation to hold it in place.
QUESTION:
What are the three main types of aeolian transportation?
ANSWER:
Suspension, saltation and surface creep.
QUESTION:
Which aeolian process removes fine particles from the ground surface, often leaving a layer of larger stones behind?
ANSWER:
Deflation.
QUESTION:
Which type of transportation moves sand grains in a series of short hops or jumps along the ground?
ANSWER:
Saltation.
QUESTION:
What is the name of the deposit made from wind-blown fine sediment such as silt?
ANSWER:
Loess.
QUESTION:
Why does dense vegetation reduce aeolian erosion and transportation?
ANSWER:
Vegetation anchors sediment with its roots and reduces the amount of loose, exposed material available for wind to move.
QUESTION:
Which process is considered a secondary process because it happens during transportation as particles collide with one another?
ANSWER:
Attrition.
QUESTION:
Wind-driven sand grains strike and wear away the surface of a rock. What is this process called?
ANSWER:
Abrasion.
QUESTION:
Which type of transportation involves larger particles rolling or creeping along the ground surface?
ANSWER:
Surface creep.
QUESTION:
A sand dune begins forming behind a shrub. What has happened to wind speed on the sheltered side of the shrub?
ANSWER:
Wind speed has decreased, causing sand to be deposited.
QUESTION:
A coastal area has strong winds and large amounts of dry sand. Why could aeolian transportation occur there even though it is not a desert?
ANSWER:
It has exposed, loose, dry sediment and strong winds, so wind can transport the sand.
QUESTION:
Which statement is correct: deflation polishes rocks, abrasion moves dust long distances, or suspension transports the finest particles?
ANSWER:
Suspension transports the finest particles over long distances.
QUESTION:
A desert rock has several flat, polished faces because the wind direction has changed over time. What type of landform is this?
ANSWER:
A ventifact.
QUESTION:
A huge dust storm carries tiny particles hundreds or thousands of kilometres. Which transportation process is mainly responsible?
ANSWER:
Suspension.
QUESTION:
Which process makes transported sand grains smaller, smoother and more rounded when they collide with each other?
ANSWER:
Attrition.
QUESTION:
Explain how a sand dune can form around a plant or other obstacle without the obstacle creating new sediment.
ANSWER:
The obstacle reduces wind speed. As wind loses energy, transported sand is deposited around it, allowing the dune to grow.
QUESTION:
A strange-looking rock formation is discovered on Mars. How could aeolian processes provide a natural explanation for unusual shapes without human or alien activity?
ANSWER:
Wind-driven abrasion can wear and polish exposed rock, while deflation can remove loose sediment. These processes can create unusual natural landforms.
QUESTION:
Explain the difference between abrasion and attrition, including what is being worn away in each process.
ANSWER:
Abrasion wears away or polishes rock surfaces when wind-blown particles strike them. Attrition occurs when transported particles collide with one another, making them smaller, smoother and rounder.
QUESTION:
A desert contains fine dust, sand and larger gravel. Wind speed suddenly decreases. Which material will be deposited first, and which will travel furthest? Explain why.
ANSWER:
The larger and heavier gravel will be deposited first, followed by sand. The finest dust can remain in suspension and travel furthest because it requires less wind energy to remain airborne.
QUESTION:
A desert rock is polished on three different faces, while nearby sand grains are becoming smaller and rounder. Identify the two main processes involved and explain what each is doing.
ANSWER:
Abrasion is polishing the rock faces as wind-blown sand strikes them. Attrition is causing the sand grains to collide with each other, making them smaller, smoother and rounder.
QUESTION:
A researcher finds a desert surface covered mainly by gravel, with very little fine sand or dust remaining. Use two aeolian processes to explain how this surface could have formed.
ANSWER:
Deflation removed the finer particles from the surface, leaving larger gravel behind as desert pavement. Wind transport may also have carried the fine material away, especially through suspension.
QUESTION:
A geographer observes dry loose sand, strong wind, sparse vegetation, polished rock faces and a large dust plume. Identify at least four aeolian processes or transportation mechanisms that could be occurring and link each one to the evidence.
ANSWER:
Deflation removes fine sediment. Abrasion polishes the exposed rock. Saltation moves sand grains in short hops. Attrition makes colliding sand grains smaller and rounder. Suspension carries the finest dust in the plume.