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Earth Science
Chapter 8
Section 2
Wind Erosion and Transport
 A current of rapidly moving air can pick up and carry
sediments
 Can only carry small particles
 Powerful agent of erosion
 Particles move in different ways
 Rolling motion along the ground
 Suspension- carried in the air for a distance
 Saltation- larger particles bounce along the ground
 Limited precipitation leads to more wind erosion
 Precipitation allows plants to grow

The plants keep the particles in place with their roots
Deflation
 Lowering of land
surface
 Wind blows particles
away
 Dust Bowl caused by
poor farming
practices removed
vegetation that held
particles in place
 Results in severe dust
storms
Deflation
 Deflation Blowout
 Shallow depressions
where sediment has
been blown away by
wind
 Vary in size from a few
meters to hundreds of
meters in diameter
 Found in areas with
sandy soil
 Major problem in
agricultural areas
Abrasion
 Particles of sand rub
against the surface of
rocks or other material
 Occurs in
 Wind
 Streams
 Glaciers
 Wind abrasion –
particles are picked up
and are blown against
anything in its path
Abrasion
 Structures can be





damaged by wind
abrasion
Powerful erosional agent
Rocks can be pitted or
grooved
Rocks can be polished
Erosion patterns
determined by direction
and force of the winds
Ventifacts- Rocks
shaped by windblown
sediments
 Ventifact
Wind Deposition
 Dunes
 Sand particles that
accumulate where an object
blocks the forward motion of
the wind
 Pile of windblown sand is
called a dune
 Windward side- gentle slope
 Leeward side- steep slope
 Conditions that affect dune
formation

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
Type and availability of sand
Amount of vegetation present
Wind direction and velocity
Windward side
Leeward side
Types of Dunes
Loess
 Wind carries fine particles,
such as silt, for long distances
 Thick windblown silt deposits
 Source of silt deposits might
have been glacial melting
during ice age
 Some of the most fertile soils
 Contain abundant minerals
and nutrients