Chapter Introduction
Lesson 1
The ErosionDeposition
Process
Lesson 2
Landforms
Shaped by
Water and Wind
Lesson 3
Mass Wasting
and Glaciers
Chapter Wrap-Up
How do erosion and
deposition shape
Earth’s surface?
What do you think?
Before you begin, decide if you agree or
disagree with each of these statements.
As you view this presentation, see if you
change your mind about any of the
statements.
Do you agree or disagree?
1. Wind, water, ice, and gravity continually
shape Earth’s surface.
2. Pieces of sediment in different sizes
tend to mix when being moved along
by water.
3. A beach is a landform that does not
change over time.
Do you agree or disagree?
4. Windblown sediment can cut and polish
exposed rock surfaces.
5. Landslides are a natural process that
cannot be influenced by human
activities.
6. A glacier leaves behind very smooth
land as it moves through an area.
The Erosion-Deposition Process
• How can erosion shape and sort
sediment?
• How are erosion and deposition
related?
• What features suggest whether erosion
or deposition created a landform?
The Erosion-Deposition Process
• erosion
• deposition
Reshaping Earth’s Surface
• A combination of constructive processes
and destructive processes produce
landforms.
• Constructive processes build up features
on Earth’s surface.
• Destructive processes tear down features
on Earth’s surface.
The breakdown of rock—weathering—
is one type of destructive process that
changes Earth’s surface.
A Continual Process of Change
• Chemical weathering alters the chemical
composition of rock.
• Physical weathering is the breaking of
rock into pieces, called sediment, without
changing the chemical composition of
the rock.
• Water, wind, and ice are agents, or
causes, of weathering.
A Continual Process of Change (cont.)
• The mineral composition of some rocks
makes them less resistant than others
are to weathering.
• The difference in the rate of weathering
can produce unusual landforms.
Erosion
• Erosion is the removal of weathered
material from one location to another.
• Agents of erosion include water, wind,
glaciers, and gravity.
• Factors that affect the rate of erosion
include weather, climate, shape of the
land, and type of rock.
Erosion (cont.)
• The presence of plants and the way
humans use the land affect the rate
of erosion.
• The rate of erosion sometimes
depends on the type of rock.
• Weathering breaks some types of rock
into large pieces. Other rock types easily
break into smaller pieces that are more
easily transported.
Erosion (cont.)
As rock fragments bump against each
other during erosion, the shapes of the
fragments can change.
How can erosion affect the
shape of sediment?
Erosion (cont.)
• Erosion also affects the level of sorting—
separating of items into groups according
to one or more properties—of sediment.
• Sediment is often well-sorted when it has
been moved a lot by wind or waves.
Erosion (cont.)
Poorly sorted sediment often results from
rapid transportation, perhaps by a storm,
a flash flood, or a volcanic eruption.
How can erosion sort
sediment?
Deposition
Deposition is the laying down or settling
of eroded material.
deposition
from French deposer, means
“put down”
Deposition (cont.)
• As water or wind slows down, it has less
energy and can hold less sediment,
which can result in some of the sediment
being deposited.
• Sediment is deposited in locations called
depositional environments, such as
swamps, deltas, beaches, and the ocean
floor.
Deposition (cont.)
• High-energy environments, like rushing
rivers and ocean shores with large
waves, are those in which sediment is
transported and deposited quickly.
• Small grains of sediment are often
deposited in low-energy environments,
like deep lakes, areas of slow-moving
air, and swamps.
• Sediment deposited in water typically
forms layers called beds.
Deposition (cont.)
How are erosion and
deposition related?
Interpreting Landforms
• Landforms can have features that are
clearly produced by erosion.
• Different rates of erosion can create
unusual landforms like tall, protruding
landforms called hoodoos.
• Glacial erosion can produce ice-carved
features in mountains.
Interpreting Landforms (cont.)
• Landforms created by deposition are
often flat and low-lying.
• An apron of sediment, called an alluvial
fan, often forms where a stream flows
from a steep, narrow canyon onto a flat
plain at the foot of a mountain.
Interpreting Landforms (cont.)
Deposition along a riverbed occurs where
the speed of the water slows down and
can result in a sandbar.
What features suggest whether
erosion or deposition created a
landform?
• Erosion occurring at different rates can
carve rock into interesting landforms.
• Rock fragments with rough edges are
rounded during transportation.
• Landforms created by deposition are
often flat and low-lying.
Which of these refers to the
breaking of rocks into sediment
without changing the chemical
composition of the rock?
A. chemical weathering
B. physical weathering
C. deposition
D. erosion
Which is an example of a lowenergy environment?
A. swamp
B. rushing river
C. ocean shore with large waves
D. none of the above
Which term refers to the laying
down or settling of eroded
material?
A. erosion
B. sediment
C. weathering
D. deposition
Do you agree or disagree?
1. Wind, water, ice, and gravity
continually shape Earth’s surface.
2. Pieces of sediment in different sizes
tend to mix when being moved along
by water.
Landforms Shaped by
Water and Wind
• What are the stages of stream
development?
• How do water erosion and deposition
change Earth’s surface?
• How do wind erosion and deposition
change Earth’s surface?
Landforms Shaped by
Water and Wind
• meander
• abrasion
• longshore current
• dune
• delta
• loess
Shaping the Land with Water and
Wind
• Water and wind are two important agents
of weathering, erosion, and deposition.
• Erosion by water and wind can change
the shape of landforms.
Water Erosion and Deposition
• Streams are active systems that erode
land and transport sediment.
• The erosion produced by a stream
depends on the stream’s energy. This
energy is usually greatest in steep,
mountainous areas where young
streams flow rapidly downhill.
• Water from a young stream slows down
as it reaches gentler slopes and is then
called a mature stream.
Water Erosion and Deposition (cont.)
• A meander is a broad, C-shaped curve
in a stream.
• A stream moves slowly when it reaches
flat land and is then called an old stream.
• As time passes, erosion of the outside
bend of a meander, where water is
flowing more quickly, occurs. Deposition
occurs on the inside bend, where water
flows more slowly.
Over time, meanders
change shape due to
erosion and deposition.
Water Erosion and Deposition (cont.)
Describe the stream
development stages.
Water Erosion and Deposition (cont.)
• Waves crashing into shore erode loose
sand, gravel, and rock along coastlines.
• A longshore current is a current that
flows parallel to the shoreline.
• This current moves sediment and
continually changes the size and shape
of beaches.
Water Erosion and Deposition (cont.)
Water erosion can also form caves, stacks,
and arches.
How does water erosion
change Earth’s surface?
Water Erosion and Deposition (cont.)
• Flowing water deposits sediment as the
water slows down.
• Slower-moving water deposits sediment
on the inside curves of meanders.
• A delta is a large deposit of sediment
that forms where a stream enters a large
body of water.
Water Erosion and Deposition (cont.)
• Much of the sand on most ocean beaches
was originally deposited by rivers.
• Longshore currents transport the sand
along ocean coasts and deposit it where
the currents have less energy.
Water Erosion and Deposition (cont.)
How does water deposition
change Earth’s surface?
Water deposition forms many structures
within caves.
Water Erosion and Deposition (cont.)
• Ocean waves can erode beaches by
removing sediment.
• To reduce erosion, people sometimes
build structures such as retaining walls
or groins.
• Reducing or removing vegetation from
the land surface is one of the most
common ways that surface erosion is
increased.
Wind Erosion and Deposition
• Abrasion is the grinding away of rock or
other surfaces as particles carried by
wind, water, or ice scrape against them.
• A dune is a pile of wind-blown sand.
Wind Erosion and Deposition (cont.)
Loess is a crumbly, windblown deposit of
silt and clay.
loess
from Swiss German Lösch,
means “loose”
Wind Erosion and Deposition (cont.)
Plowed fields and dry, overgrazed
pastures are two ways in which people
contribute to wind erosion.
How do wind erosion and
deposition change Earth’s surface?
• Water erosion changes Earth’s surface.
An example of this is the change in
features of a stream over time.
• Water transports sediment and deposits
it in places where the speed of the water
decreases.
• Wind erosion can change Earth’s
surface by moving sediment. A dune and
loess are two types of wind deposition.
Which term refers to the grinding
away of rock or other surfaces as
particles carried by wind, water,
or ice scrape against them?
A. meander
B. delta
C. longshore current
D. abrasion
Which is a pile of wind-blown
sand?
A. loess
B. dune
C. delta
D. meander
What is a current that flows
parallel to the shoreline?
A. meander
B. delta
C. longshore current
D. loess
Do you agree or disagree?
3. A beach is a landform that does not
change over time.
4. Windblown sediment can cut and
polish exposed rock surfaces.
Mass Wasting and Glaciers
• What are some ways gravity shapes
Earth’s surface?
• How do glaciers erode Earth’s
surface?
Mass Wasting and Glaciers
• mass wasting
• till
• landslide
• moraine
• talus
• outwash
• glacier
Mass Wasting
• Mass wasting is the downhill movement
of a large mass of rocks or soil because
of the pull of gravity.
• Mass wasting commonly occurs when
soil on a hillside is soaked with
rainwater.
• A landslide is the rapid downhill
movement of soil, loose rocks, and
boulders.
Mass Wasting (cont.)
• Two types of landslides are a rockfall
and a mudslide.
• Slump is a type of mass wasting where
the material moves slowly, in a large
mass.
• If the material moves too slowly to be
noticeable, causing trees and other
objects to lean over, the event is called
creep.
Mass Wasting (cont.)
What are some ways gravity shapes
Earth’s surfaces?
Mass Wasting (cont.)
• When material reaches a stable location,
such as the base of a mountain, the
material is deposited.
• Talus is a pile of angular rocks and
sediment from a rockfall.
Mass Wasting (cont.)
• Human activity, such as removing
vegetation, can affect both the severity of
mass wasting and the tendency for it to
occur.
• Landscaping or building on a slope can
make the slope steeper and more likely
to undergo mass wasting.
Glacial Erosion and Deposition
• A glacier is a large mass of ice that
formed on land and moves slowly across
Earth’s surface.
• The two main types of glaciers are alpine
glaciers and ice sheets.
• Glaciers erode Earth’s surface as they
slide over it, carving the land as they
move.
Alpine glaciers produce distinctive
erosional features.
Glacial Erosion and Deposition (cont.)
How do glaciers erode Earth’s
surface?
Sediment that was frozen in a glacier’s ice
is eventually deposited in various forms.
Glacial Erosion and Deposition (cont.)
Till is a mixture of various sizes of
sediment deposited by a glacier.
till
Science Use rock and sediment
deposited by a glacier
Common Use to work by plowing,
sowing, and raising crops
Glacial Erosion and Deposition (cont.)
A moraine is a mound or ridge of unsorted
sediment deposited by a glacier.
moraine
from French morena, means
“mound of earth”
Glacial Erosion and Deposition (cont.)
• Outwash is layered sediment deposited
by streams of water that flow from a
melting glacier.
• A small change in Earth’s average
temperature causes considerable
melting of glaciers.
• As glaciers melt, sea level rises around
the world.
• Mass wasting can occur very fast,
such as when a landslide occurs, or
slowly over many years.
• Material moved by a mass wasting
event is deposited when it reaches a
relatively stable location. An example
is talus deposited at the base of a hill.
• A glacier erodes Earth’s surface as it
moves and melts. Glaciers can form
U-shaped
valleys when
they move
past
mountains.
Which of these describes a type of
mass wasting where the material
moves slowly, in a large mass?
A. slump
B. talus
C. till
D. moraine
A large mass of ice that formed
on land and moves slowly across
Earth’s surface is called what?
A. glacier
B. landslide
C. slump
D. talus
Which term refers to a mound or
ridge of unsorted sediment
deposited by a glacier?
A. till
B. outwash
C. moraine
D. talus
Do you agree or disagree?
5. Landslides are a natural process that
cannot be influenced by human
activities.
6. A glacier leaves behind very smooth
land as it moves through an area.
Key Concept Summary
Interactive Concept Map
Chapter Review
Standardized Test Practice
Erosion and deposition
are constructive and
destructive forces that
shape Earth’s surface
by building up and
tearing down
landforms such as
coastlines, dunes,
rivers, lakes,
mountains, glaciers,
and deltas.
Lesson 1: The Erosion-Deposition
Process
• Erosion is the wearing away and transportation of
weathered material. Deposition is the laying down of
the eroded material.
• Erosion tends to make rocks more rounded. Erosion
can sort sediment according to its grain size.
• Landforms produced by deposition are usually on
flat, low land. Landforms produced by erosion are
often tall and/or jagged.
Lesson 2: Landforms Shaped by
Water and Wind
• A young stream moves quickly down steep slopes.
A mature stream moves more slowly and develops
meanders. An old stream is wider and moves
slowly.
• Water erosion forms V-shaped valleys. Longshore
currents reshape beaches. Deposition of sediment
from water can form deltas.
• Wind abrasion can alter the shape of rock. Wind
deposition can form a dune or loess.
Lesson 3: Mass Wasting and Glaciers
• Gravity can shape Earth’s surface through mass
wasting. Creep is an example of mass wasting.
• A glacier erodes Earth’s surface as it moves by
carving grooves and scratches
into rock.
Which process always alters the
chemical composition of rock?
A. physical weathering
B. chemical weathering
C. deposition
D. erosion
Locations where sediment is
deposited are referred to as
which of these?
A. hoodoos
B. alluvial fan
C. depositional environments
D. swamp
What is a large deposit of sediment
that forms where a stream enters
a large body of water?
A. longshore current
B. delta
C. dune
D. meander
Which term refers to a broad,
C-shaped curve in a stream?
A. mature stream
B. delta
C. loess
D. meander
A pile of angular rocks and
sediment from a rockfall is
referred to as which of these?
A. landslide
B. talus
C. glacier
D. slump
Which term refers to the removal
of weathered material from one
location to another?
A. deposition
B. erosion
C. physical weathering
D. chemical weathering
What is a stream called when it
reaches flat land and moves
slowly?
A. old stream
B. longshore current
C. delta
D. creep
Which term refers to a crumbly,
windblown deposit of silt and
clay?
A. dune
B. loess
C. delta
D. meander
Which of these is the dominant
cause of mass wasting?
A. rain
B. soil
C. gravity
D. erosion
Which of these refers to a mixture
of various sizes of sediment
deposited by a glacier?
A. till
B. outwash
C. moraine
D. talus