Download earthquakes and mountain building ppt

Earth’s Crust in Motion
Long Island Earthquake!!
• http://www.youtube.com/watch?feature=pl
ayer_detailpage&v=STsn_esGbVM
• When the Earth’s plates are in motion,
earthquakes may occur.
• Tier Word
• Motion-movement
.
STRESS
• The movement causes stress in the crust.
• There are 3 types of stress in the crust
• Stress -pressure
Musical sliders
Tensional Stress
(gum)
Compressional Stress(trash compacter)
What happens during an
earthquake?
• The stress builds and then releases. This
is the energy in an earthquake.
• An earthquake is the shaking and
trembling that is caused by the movement
of rock beneath Earth’s surface.
Faults
• Earthquakes are caused by stress at fault
lines.
• A fault line is found at the boundaries of
two different lithospheric plates.
• (it’s the faults fault! )
• haaaaaaaaaaaa
Do
Now
• Name/Draw three types of stress in
Earth’s Crust.
• Shearing
• Compression
• tension
• HW study today’s notes
• Test next week
• Volcanoes, earthquakes, mountain
Strike slip fault
• Caused by shearing
• Rocks slip past each other
• San Andreas Fault
Strike,slip
• Normal faults -the land is pulling apart or
stretching.
• The tension in the crust increases until the
rocks fracture.
• One block of land slips downward
•
Fracture-break
Reverse
• Forms by compression
• hanging wall slides up and over
footwall
• formed Appalachian Mountains
(Thrust)
Fault
• http://www.iris.edu/gifs/animations/faults.ht
m
• http://science.howstuffworks.com/nature/n
atural-disasters/earthquake3.htm
Safety Tips
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Have an earthquake readiness plan.
bolt bookcases to wall studs,
Find a room of the house that you can go to in case of an earthquake. It
should be a spot where nothing is likely to fall on you.
Keep a supply of canned food, an up-to-date first aid kit, 3 gallons (11.4
liters) of water per person, dust masks and goggles, and a working batteryoperated radio and flashlights.
Know how to turn off your gas and water mains.
.
Safety
Mountain Building
• Takes millions of years
• Caused by compression/converging
forces
• Formed by folding –bends in rock that
form when compression shortens and
thickens part of Earth’s crust
Mountain Building Cont.
• Syncline
• Anti-cline
• Plateau
dip
=
peak
rock bends into an arch
=large area of flat land
elevated high above sea
level
Colorado Plateau
Folding
Syncline
(trace with your finger)
Syncline
Syncline
Anticline(folded arch rock)
Anti-Cline-fold
Tier Words to Know for the Test
and Beyond
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Compress –squeeze
compressional, compressing
Geologic event (earthquakes, volcanoes)
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Interior-inside
Motion -movement
Anything that starts with the prefix geo-earth
Volcanologist- studies volcanoes
Seismologist- studies earthquakes
Diverge –separate
–
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Converge- come together
–
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transforming
Stress –pressure/tension
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Convergent, converging
Transform- slip past
–
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Divergent, diverging
Stressful, tensional
Primary- first,main
Questions to Think About
Essential Questions:
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Can we predict earthquakes? Can we predict when
volcanoes will erupt?
• What do earthquakes and volcanoes tell us about what
is happening inside the earth and on the surface?
• Do you have to worry about a volcanic eruption or
• earthquake where you live? Why or why not?
Stop
Enduring Understandings:
–
Studying historical earthquakes and volcanic eruptions improves our
understanding of earth's processes.
– Although it is known where earthquakes and volcanic eruptions are likely to
happen, there is currently no reliable way to predict precisely when an event will
occur.
– Volcanoes and earthquakes indicate the high temperatures and pressures that
exist in earth's interior.
– Volcanism(volcanic activity) and seismic(earthquake) activity vary across the
globe
Common misunderstandings
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What do students typically misunderstand?
Earthquakes don’t only occur when whole plates slide past each other.
Earthquakes don’t create a gap or hole in the earth's surface.
Earthquakes don’t occur at one depth.
Lava that erupts out of a volcano does not comes from earth's core.
Earthquakes don’t cause volcanic eruptions.
Plate boundaries are not the same as faults.
Lava does not come out of all volcanic eruptions