Download Geohazards

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* You need to create a foldable on geo-hazards
* The title page must include the title “Geo-hazard” and an
explanation in your own words
* You need to include the following Geo-hazards – Landslides,
Earthquakes, Volcanoes, Tsunamis, Sinkholes and Flooding
* You must describe each hazard
* You must include precautions for each geo-hazard
* You need to include at least 3 pictures
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*A geohazard is a geologic event
that has the potential to both
destroy property and cause a loss of
life
* Landslide
* Earthquake
* Tsunami
* Sinkhole
* Flooding
* Volcanoes
*A landslide is where
debris separates from
bedrock and the
material slides rapidly
down slope
Caused by:
*Over steepened slope
*Removal of
vegetation
*Earthquakes
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Ways to avoid landslide
damage
*Don’t build homes on
areas of weak soil
*Replant trees
*Slopes can be sprayed
with concrete to reduce
rock slippage
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Rapid downslope movement of Earth
materials.
Caused by heavy rainfall, flood,
earthquake, erosion, and human activities
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*Avoid building on steep, unstable
slopes.
*Cover the slopes with metal netting.
*Build retaining wall at bottom of slope.
*Education
*Total avoidance of area
*Restriction of land
*Design or refit building to be resistant
*Prevent erosion
*Avoid weak slopes
*Structural examples nets and walls
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*Earthquakes occur
when tectonic plates
slide past each other,
slip and release seismic
waves
*Ways to mitigate
earthquake damage:
*Secure bookshelves in
home
*Secure gas/water
heater
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Precautions:
*Buildings should meet earthquake
construction requirements.
*Have heavy items close to the ground.
*Make buildings more stable no store or
concrete.
*Use wood or steel frames
*Rest structures on large rubber structures
that absorb most vibration from Earthquakes
*Use Earthquake resistant buildings
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*Volcanoes release dust and ash which
can alter the climate by blocking out the
sun
*As well they can trigger mudslides and
send lava down a mountainside
*This contour map
represents a volcano
*The lava and ash
flow would have to
flow North due to
the sharp drop in
elevation on the
Northward side
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*If a lahar, pyroclastic flow, or lava flow is
headed toward you
*Leave the area immediately. If you are warned
to evacuate because an eruption is imminent,
evacuate.
*If you can drive rather than walk, use your
vehicle to evacuate. When driving keep doors
and windows closed, drive across the path of
danger if you can or away from the danger if
you can not, and watch for unusual hazards in
the road
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If you are indoors:
*Close all windows, doors, and fireplace or
woodstove dampers.
*Turn off all fans and heating and air
conditioning systems.
*Bring pets and livestock into closed
shelters.
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If you are outdoors:
*Seek shelter indoors.
*If caught in a rockfall, roll into a ball to protect your head.
*If near a stream or river, be aware of rising water and possible
mudflows in low-lying areas. Move up-slope as quickly as
possible.
*Seek care for burns right away. Immediate care can be life
saving.
*If your eyes, nose, and throat become irritated from volcanic
gases and fumes, move away from the area immediately. Your
symptoms should go away when you are no longer in contact
with the gases or fumes. If the symptoms continue, consult
your doctor.
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*Protecting yourself during ashfall
*Stay inside, if possible, with windows and doors
closed.
*Wear long-sleeved shirts and long pants.
*Use goggles to protect your eyes. If ash is continually
falling, you may not be able to shelter indoors for
more than a few hours, because the weight of the ash
could collapse the roof of your building and block air
intakes into the building. Listen to authorities for
advice on leaving the area when ashfall lasts more
than a few hours.
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*Avoid active area
*Ash fall have proper filters
to reduce damage
*Redirect small lahars
*Education
*A tsunami is a large
tidal wave that is
generated by seismic
waves released from
an earthquake
*Slab of crust is
displaced along a
fault
*Can travel up to
500-950 kilometers
per hour
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*Ways to mitigate
tsunami damage:
*Preserve dunes on
beaches  Provide
inland protection
from tsunamis
*Build trenches to
divert water
*Build seawalls to
protect inland
areas
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*A giant wave caused by
an underwater
earthquake.
Precaution:
*Listen to news for a
warning
*Move away from the
shore and to higher
ground
*Do not go to the beach
even if you see water
receding
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*Build structures at least 200
meters from high tide line
*Reinforce building structures to
withstand impact from wave
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*A sinkhole is a
natural depression
on the Earth’s
surface
*Can be caused
by collapse of
underlying rock
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*
*Mitigation:
*Use filters  Pump out water which
dissolve underlying rock
*Careful inspection of bedrock
*Test soil composition before
building
*Treat underground limestone to
resist water
*Redirect surface water
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*Groundwater-Water stored beneath the surface
*Becomes polluted when chemical seep into the
ground and contaminate the aquifer
*This can contaminate wells and a communities
drinking water
*Build impermeable underground barriers
*Treat groundwater before using
*Be aware of well location
*Keep hazards such as pesticides and gasoline
away from well
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*Flooding occurs over an area where
water cannot seep into the soil
*Soil is impermeable or saturated
*Natural event when water
flows over the banks of
rivers.
Precautions:
*Recognize clues such as
heavy rains, topography
and flood history.
*Learn evacuation routes.
*Keep vehicle fueled since
power failure may render
service stations inoperable.
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*Mitigation:
*Flood risk maps
*Don’t build homes
on flood plains
*Redirecting
waters through
flood channels
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