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Chapter Menu
Lesson 1: Weathering
Lesson 2: Erosion and Deposition
Lesson 3: Reshaping the
California Landscape
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8.1 Weathering
weathering
chemical weathering
physical weathering
frost wedging
soil
8.1 Weathering
Weathering
• The process that breaks down and changes
rocks that are exposed at Earth’s surface
• Caused by the action of water, wind, ice,
and gravity
Weathering
8.1 Weathering
Chemical Weathering
• When minerals and rocks at Earth’s surface
are weakened and broken down from
exposure to water and gases in the
atmosphere
• Changes the composition of minerals in
rocks and forms new minerals
8.1 Weathering
Chemical Weathering (cont.)
• Water: most common agent of
chemical weathering
• Carbon dioxide
• Sulfur dioxide
• Oxygen
8.1 Weathering
Rock Type and Weathering
• Type of rock determines how quickly its
surface is chemically weathered
• Granite or slate resists chemical weathering
better than limestone or marble.
8.1 Weathering
Physical Weathering
• The breaking of rock into smaller pieces
without changing its mineral composition
– Frost wedging—when water freezes,
expands, and melts in the cracks of rocks
– Plants and animals
8.1 Weathering
Soil
• A mixture of weathered rock, minerals,
and organic matter
• Formation affected by the type of rock,
climate, length of time rock weathering, and
the interaction of plants and animals
• Contains the nutrients necessary for plant
growth and food crop production
8.1 Weathering
Soil (cont.)
• Residual soil: soil that remains in the
same location where formed
• Transported soil: soil developed from
weathered material that has been moved to a
new location by wind, water, or glaciers
8.1 Weathering
Soil (cont.)
8.1 Weathering
Soil Layers
• Called soil horizons and take thousands
of years to develop
• A horizon: topmost soil horizon composed
small rocks, minerals, and humus
• B horizon: contains the dissolved minerals
from A horizon
• C horizon: consists partly of weathered
parent material or bedrock
8.1 Weathering
What is chemical weathering?
A breaking rock into
smaller pieces
B the mineral composition
is changed due to
exposure to water and
gases in the atmosphere
C process in which plant
roots break rocks apart
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D frost wedging
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8.1 Weathering
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D
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What is physical weathering?
A breaking of rock into smaller
pieces with no change in
mineral composition
B changing the composition
of minerals and rocks by
exposure to water
C acidic rainwater reacts
with minerals changing
them into different minerals
D oxygen is dissolved in
water starting a chemical
reaction
B
A
B
C
D
A
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8.1 Weathering
If soil remains in the same location
where it formed, what is it called?
A transport
B A horizon
C C horizon
D residual
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8.2 Erosion and Deposition
erosion
flood
deposition
flood plain
mass wasting
beach
landslide
glacier
meanders
8.2 Erosion and Deposition
Erosion
• Process of wearing away rock or soil
• Can be caused by running water, rain,
waves, glaciers, wind, and gravity
(landslides)
• Deposition: when sediments are laid down
in a new location by one of these processes
How are materials
from the Earth
broken down?
8.2 Erosion and Deposition
Mass Wasting
• Form of erosion caused by gravity
• Downhill movement of rocks and/or soil in
one large mass
• Usually occurs when the ground is
saturated with rainwater but can be
triggered by vibrations from earthquakes,
heavy machinery, and blasting
• Steeper the slope of hillside, the more likely
mass wasting will occur
8.2 Erosion and Deposition
Mass Wasting (cont.)
• Landslides: rapid, gravity-caused events
that move soil, loose rock, and boulders
• Mudslides: mixtures of soaked soil and rock
• Rock falls: loosened rock falling from
steep cliffs
• Slumps: a block of rock and overlying soil
slide down as one large mass
• Creep: sediment moves slowly downhill
8.2 Erosion and Deposition
Climate and Erosion
• Climate determines amount of water a
region receives
• Regions with large amounts of rain more
likely to experience mass wasting
• Presence of thick vegetation on slopes
tends to prevent landslides because the
plants’ root systems hold sediment in place
8.2 Erosion and Deposition
Meanders
• Curves in a stream or river
• Develop on gentler slopes when stream
erodes sides of stream bed instead of bottom
due to slower stream flow
8.2 Erosion and Deposition
Meanders (cont.)
8.2 Erosion and Deposition
Deposition
• Sediment and rock that are eroded and
carried by river systems are transported
and eventually deposited at a new location.
– Oxbow lakes
– Delta
– Alluvial fans
8.2 Erosion and Deposition
Deposition (cont.)
8.2 Erosion and Deposition
Flood
• When the water level in a river rises above
the usual height and overflows its banks
• Floodplain: a wide, flat valley located
along the sides of rivers and streams
8.2 Erosion and Deposition
Levees
• Protect area from flooding
– Natural levees: long, low ridges formed
by sediment carried by floodwaters and
deposited along the floodplain
– Artificial levees: human–made structures
built to help control floodwaters
8.2 Erosion and Deposition
Beaches
• Landform consisting of loose sand and gravel
• Dynamic, actively changing systems
• Sand supplied by the continuous flow of
rivers to oceans
8.2 Erosion and Deposition
Erosion Features
• Cliffs: formed by the cutting action of waves
• Eroded cliffs move back from the shoreline
and leave behind a flat area called a wavecut platform
• Sea caves, sea stacks, and sea arches
can form when waves erode the softer
portions of rocks.
8.2 Erosion and Deposition
Longshore Current
• Movement of
the water that
moves large
amounts of
sediment along
coasts
8.2 Erosion and Deposition
Erosion Prevention
• Shoreline armoring: retaining walls, harbor
channels, and groins
• Changes natural shoreline processes but is
necessary to prevent collapse of cliffs or the
complete destruction of a beach
8.2 Erosion and Deposition
Glaciers
• Large masses of ice and snow
• Form in areas where amount of annual
snowfall is greater than the meltoff
• Formation takes hundreds to thousands
of years
• Movement is about 2.5 cm/day
8.2 Erosion and Deposition
Glaciers (cont.)
• Valley glaciers (alpine glaciers): form in
existing stream valleys high in the mountains
• Continental glaciers (ice sheets): cover entire
land areas, only located in Antarctica and
Greenland
8.2 Erosion and Deposition
Glaciers (cont.)
8.2 Erosion and Deposition
Glaciers and Erosion
• Glaciers erode surfaces as they pass
over them.
• Trapped rocks and boulders at the bottom
of the ice create grooves and scratches as
the glacier moves.
• Grooves and scratches show the direction
the glacier was moving.
8.2 Erosion and Deposition
Deposition and Glaciers
• Till: sediment deposited by glacier that
often builds up along the sides and fronts
of glaciers into long, high ridges called
moraines
• Outwash: sediment
deposited by glacier;
consists mostly of
sand and gravel
8.2 Erosion and Deposition
Wind Erosion and Deposition
• Wind lifts and redeposits loose material.
• Sand dunes: mounds and ridges that form
from heavier sediment that blows along the
ground
• Loess: deposit that consists of wind-blown
silt that is carried in the air
8.2 Erosion and Deposition
What is it called when gravity slowly
pulls sediment downhill?
A landslide
B rock fall
C creep
D slump
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8.2 Erosion and Deposition
_____ is when sediments are laid
down in a new location.
A Erosion
B Deposition
C Meander
D Playas
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8.2 Erosion and Deposition
What is shoreline armoring used for?
A to prevent beach erosion
B to produce electricity
C to dam rivers
D to prevent rock slides
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8.3 Reshaping the
California Landscape
basin and range
arroyo
8.3 Reshaping the California Landscape
California Landscapes
8.3 Reshaping the California Landscape
Mountains of California
• U-shaped valleys
• Hanging valleys
• Moraines
• Steep white-water streams in V-shaped
valleys
8.3 Reshaping the California Landscape
Deserts of California
• Mostly located in the southeastern corner
• Flat, sandy valleys
• Playas: dry lakebeds
• Alluvial fans
• Wind-blown sand dunes
8.3 Reshaping the California Landscape
Basin and Range
• Large area of north-south trending
mountain ranges and valleys
• Primarily located in Nevada and Utah
• Has desert climate
8.3 Reshaping the California Landscape
Death Valley
• Lowest point in the western hemisphere
(86 m below sea level)
• Arroyo: streambed that only contains water
during heavy rains or floods
8.3 Reshaping the California Landscape
Rivers of Central Valley
• Sacramento River: south-flowing river
located in the north part of the valley
• San Joaquin River: north-flowing river
located in the south part of the valley
• Abundant river sediment provides the
valley with a thick fertile soil and has made
it the most productive agricultural area in
California.
8.3 Reshaping the California Landscape
Coastal Landscapes
• California’s beaches can change due to
different seasonal conditions.
• El Niño caused many landslides and
general erosion.
8.3 Reshaping the California Landscape
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What is the Basin and Range area?
A large area of east-west trending
mountain ranges and valleys
located primarily in Nevada
and Utah
B large area of north-south trending
rivers and oceans located
primarily in Nevada and Utah
C large area of east-west trending
mountain ranges and valleys
located primarily in New York
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and Pennsylvania
D large area of north-south trending
mountain ranges and valleys
located primarily in Nevada and Utah
B
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B
C
D
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8.3 Reshaping the California Landscape
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What is an arroyo?
A streambed that only
contains water during
heavy rains or floods
B wide, flat valley located
along the sides of some
rivers and streams
C desert climate
D mixture of weathered
rock, minerals, and
organic matter
B
A
B
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D
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8.3 Reshaping the California Landscape
Which of the following is an example
of a glaciated mountain feature?
A V-shaped valleys
B meandering rivers
C U-shaped valleys
D U-shaped mountains
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D
C
Which of the following is a form of glacial
erosion?
A rocks and boulders
trapped at the bottom of
the ice create grooves
and scratches
B sand dunes form from
heavier sediment
C arroyos form
D soil that develops from
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weathered material is
moved to a new location
by landslides
B
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D
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What is mass wasting?
A when a stream erodes
a steep valley to a
gentle slope
B a form of erosion caused
mainly by gravity
C sediment that is
eroded and transported
downstream
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D sediment, mostly sand
and gravel, transported
by glaciers
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What type of glacier forms in stream
valleys high in the mountains?
A till
B moraine
C alpine
D continental
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Copper statues that turn green are
exhibiting _____ weathering.
A physical
B no
C chemical
D transformation
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Deposition on the inside of a meander
can cut off part of the river resulting
in what?
A playa
B oxbow lake
C deltas
D alluvial fan
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SCI 2.a
Which soil layer contains the most
decomposed plant matter?
A A horizon
B B horizon
C C horizon
D none of the above
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SCI 2.b
Which of the following is a form of
fast mass wasting?
A creep
B slump
C meander
D longshore transport
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SCI 2.a
What does feldspar change into
when it comes in contact with
acidic rainwater?
A iron
B granite
C quartz
D clay
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SCI 2.b
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D
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In what areas are V-shaped valleys
common?
A flat, sandy valleys of
some California deserts
B wide, meandering rivers
of California plains
C high, steep parts of
some California
mountains
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D wind-blown area of
California deserts
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SCI 1.f
What is the name and location of the
largest present-day glacier in
California?
A Palisade Glacier in
the Mojave
B Palisade Glacier in
the Sierra Nevada
C Colorado Glacier in the
Sierra Nevada
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D Colorado Glacier in
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