Erosion and WeatheringNatural hazards
Made By: Haley Cioni and
Madison Keegan
Weathering
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Weathering is the breaking down
of rock, soils and minerals as well
as artificial materials through
contact with the Earth’s
atmosphere, biota and waters.
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Two important classifications of
weathering processes exist –
physical and chemistry
weathering; each sometimes
involves a biological component.
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The materials left over after the
rock breaks down combined with
organic material creates soil.
Erosion
• Erosion is the process by
which soil and rock are
removed from the Earth’s
surface by natural processes
such as wind or water flow,
then transported and deposited
in other locations.
• Water and wind erosion are
now the two primary causes of
land degradation ;combined
they are responsible for 84% of
degraded acreage.
Different Types of Weathering
Different Kinds of Weathering and
Erosion
Causes of Weathering and Erosion
• Atmospheric erosion-the suns
heat causes surface rocks to
expand and fracture, and
moisture can evaporate.
• Biological erosion-many plants
secrete acids in their roots.
Root structures also enlarge
cracks seeking water. Animals
crush surface rocks and
deposit organic materials that
interact with minerals.
Factors Controlling the Rate of
Erosion
• Precipitation and wind
speed
• Soil structure and
composition
• Vegetative cover
• Topography
Differences between weathering
and erosion
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Weathering involves two
processes that often work in
concert to decompose rocks. Both
processes occur in place. No
movement is involved in
weathering. The two types of
weathering are called chemical,
and mechanical weathering
As soon as a rock particle moves
we call it erosion or mass wasting.
Mass wasting is simply movement
down slope due to gravity.
So the difference is that
weathering involves staying in
place and erosion involves
movement.
Soil Erosion
• Soil erosion by water,
wind, and tillage affects
both agriculture and the
natural environment.
• Soil loss, and its
associated impacts, is
one of the most important
of today's environmental
problems.
Study of historic Hopi Buttes Area
• Hopi Buttes volcanic field is a
monogenic volcanic field
located on the Colorado
plateau mostly on the Navajo
Reservation around the town
of Dilkon.
• Most of the volcanic activity
occurred between 8.5 and 6
million years ago with the most
recent dated 4.2 million years
ago.
Erosion in the Southwest
• Erosion is carving into
Southwest Washington
beaches. Erosion rates at
Cape Shoal water have
averaged over 100 feet
per year for a century.
• In recent decades, new
erosion hot spots have
developed.
Coastal Erosion Prevention
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Seawalls, which run parallel to the
coast are one of the most
common responses two coastal
erosion. They help stabilize the
beach.
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Groynes- are structures that
prevent erosion by limiting water
flow
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Vegetation- planting vegetation
such as trees defends the coast
line.
•
Offshore breakwaters- are
submerged structures that parallel
the shore.
Wind Erosion Prevention
• Wind erosion happens when
the soil is left unprotected from
the strong winds. The loss of
topsoil lowers the quality of the
soil.
• This makes it more expensive
and harder to grow food crops.
• The blowing soil can also plug
ditches, make driving more
difficult, plug ventilation,
equipment and so on.
Beach Erosion Prevention
• Beach erosion is the
movement of beach materials
by wave action, currents and
tides, or wind.
• Many ways to prevent beach
erosion are available. Natural
dunes and vegetation are slow
forming but more durable than
unnatural dunes and
transplanted vegetation. Man
made structures include
seawalls, sandbags, and sand
fences.
Geological hazard: landslide
• Landslides constitute a major
geological hazard because
they are widespread, occur in
all 50 states and U.S
territories, and cause $1-2
billion in damage and more
than 25 faculties on average
each year.
• Landslides commonly occur in
connection with natural
disasters like, earthquakes,
volcanoes, wildfires, and
floods.
Federal Emergency Management
Agency- Landslides and Mudslides
• The Federal Emergency
Management Agency (FEMA)
is a agency of the United
States department of
homeland security, initially
created by Presidential
Reorganization Plan No.3 of
1978 and implemented by two
executive orders on April 1,
1979.
• To prevent mudslides and
landslides they look for dues to
know when they will occur.
Then they will try to prevent
them as best as they can.
Solution!!!
• Some solutions for erosion are
seawalls, sandbags, and sand
fences. Also some more are
gyrones, vegetation, and
offshore breakwaters.
• This is a way to prevent the
worse of weathering and
erosion. In the future I believe
they will come up with more
solutions to prevent these
natural hazards.
Thanks for watching!!!
Reference Page: Part 1
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http://educatoral.com/weathering_erosion_webques.html
http://en.wikipedia.org/wiki/Weathering
http://en.wikipedia.org/wiki/Erosion
http://facstaff.gpc.edu/~pgore/geology/geo101/weather.htm
http://science.nationalgeographic.com/science/photos/weathering-erosiongallery.html#baffin-island_832_600x450.jpg
http://wiki.answers.com/Q/What_causes_weathering_and_erosion
http://en.wikipedia.org/wiki/Erosion
http://geomaps.wr.usgs.gov/parks/misc/gweaero.html
Reference Page 2
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http://soilerosion.net/
http://en.wikipedia.org/wiki/Hopi_Buttes_volcanic_field
http://www.ecy.wa.gov/programs/sea/coast/erosion/study.html
http://www.advancedcoastaltechnology.com/
http://www.environment.ualberta.ca/SoilPosters/wind.cfm
http://wiki.answers.com/Q/What_causes_beach_erosion
http://landslides.usgs.gov/
http://en.wikipedia.org/wiki/Federal_Emergency_Management_Agency
http://www.fws.gov/fire/ifcc/esr/Media/FEMA%20landslides%20are%20you
%20ready.pdf