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Flashcards in Section 8.2 Deck (8)
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1
Q

What is one way that wind erosion differs from water erosion?

A

They both can pick up sediments and move them, but, except for the extreme winds of hurricanes, tornadoes, and other strong storms, winds generally cannot carry particles as large as those transported by running water.

2
Q

What is suspension?

A

A method of transport by which strong winds cause particles to stay airborn for long distances.

3
Q

What is saltation?

A

Causes a bouncing motion of particles. Accounts for most sand transport caused by wind.

4
Q

What is deflation?

A

The lowering of the land surface that results from the wind is removal of surface particles. The particles removed may be composed of any material. In areas of intense wind erosion, course material is left behind and the finer material is removed.

5
Q

What is abrasion? What do materials exposed to wind abrasion look like?

A

Occurs when particles, such as sand, rub against the surface of rocks or other materials. Occurs as part of the erosion all activities of winds, streams, and glaciers. Wind picks up materials and blows them against rocks and other objects which an eventually wear away structures such as rocks, or paint on homes. Materials exposed to wind abrasion show unique characteristics such as rocks becoming pitted and grooved and which continual abrasion becoming polished and smooth with sharp edges.

6
Q

When do sand dunes form? What do the conditions under which a dune forms determine? What are those conditions?

A

When particles accumulate where an object has block the particles’ foreward movement. Over time, the pile of wind-blown sand developes into a dune. The conditions under which a dune forms determine its shape. Conditions include the availability of sand, wind velocity, wind direction, and the amount of vegetation present.

7
Q

Sand dunes
Gentle slope=___
Steeper slope=___
Wind velocity=___

A

Gentle slope=side wind blows
Steeper slope=side protected from wind
Wind velocity=height of the dune

8
Q

What is loess?

A

Wind carries fine, lightweight particles such as silt and clay in great quantities for long distances. Many parts of Earth’s surface are covered by thick layers of wind blown silt. These thick, wind blown silt deposits are known as loess. When precipitation is adequate, loess soils can be some of the most fertile soils on Earth because they contain abundant minerals and nutrients.