Download Wind - De Soto Area School District

Wind
Earth’s Changing Surface
Review
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5 Agents of Erosion
Gravity
 Running Water
 Glaciers
 Wind Waves
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Erosion by Wind
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Wind by itself is the weakest agent of erosion.
Powerful force where there are few plants to
hold the soil in place.
Wind Erosion
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Deflation
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The process by which wind removes surface
material.
Abrasion
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Abrasion
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Sand carried by wind can polish rocks
Wind Deposition
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Wind Erosion and Deposition form sand dunes
and loess deposits.
Sand dunes – A deposit of wind-blown sand
Forms when the wind strikes an obstacle. The
sand then begins to pile up.
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Sand dunes move over time
Sand Dune
Sand Dune Worksheet
Loess Deposits

Sediment that is finer than sand, such as
particles of clay and silt, is sometimes deposited
in layers far from its source.
Waves
Earth’s Changing Surface
How are Waves formed?
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The energy in waves comes from wind that
blows across the water’s surface.
Waves
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Waves shape the coast through erosion by
breaking down rock and transporting sand and
other sediment.
Erosion by Waves
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Impact – large waves can hit rocks. The energy
in waves can break apart rocks.
Abrasion – sediment picked up by waves wear
away rock.
Waves changing direction – waves begin to drag
on the bottom as they approach the shore.
Deposits by Waves
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Waves shape a coast when they deposit
sediment, forming coastal features such as
beaches, spits, and barrier beaches.
Beaches
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As waves reach the shore, they drop the
sediment they carry, forming a beach
A Beach is an area of wave-washed sediment
along a coast.
Usually sand
 Some are made of small fragments of coral or sea
shells, Florida

Beach in Southern California
Lake Superior Beach
Florida Keys Beach