Download Unit 6 Earthquakes and Volcanoes

Unit 6 Earthquakes
and Volcanoes
Warm Up Friday
Analyze this bar graph- this graph compares
deaths from EARTHQUAKES per time period
How are Richter Scales and Mercalli
Intensity Scale connected?
Both measure earthquakes
How are they not connected?
Richter Scales measure magnitude
and Mercalli Scales measure
observable damage.
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Moving rocks get caught on each other at
faults.
Moving rocks create STRESS points
The breaking point is reached
Energy is released
Earthquakes
1. What are
earthquakes?
1.
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Earthquakes are
movement of earth’s
crust caused by plates
shifting and releasing
stored energy
Rocks on either side of a
fault snag and build up
pressure
When the rocks break ...
shake, rattle and roll!
http://videos.howstuffworks.com/hsw/5934-geology-earthquakes-video.htm
Earthquakes
2. What are seismic
waves?
2. Seismic waves are
shock waves in the
earth caused by an
earthquake.
Earthquakes
3. What are P waves?
3. P waves are primary
waves. They are fast
and longitudinal
( push and pull forces)

P waves are the to 'arrive' at
a seismic station. The P wave
can move through solid rock
and fluids, like water or the
liquid layers of the earth. It
pushes and pulls the rock it
moves through just like sound
waves push and pull the air.
Earthquakes
4. What are S waves?
4. S waves are secondary
or shear waves. They are
slower. S waves are
transverse- move from
side to side.
S waves move rock
particles up and down,
or side-to-side—
perpendicular to the
Direction of the wave.
http://aspire.cosmicray.org/labs/seismic/index.htm
Earthquakes
5. What are L waves?
5. L waves are “love waves”
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Named after a
British scientist who
calculated a
mathematical model
for a wave.
L Waves are the
fastest waves and
move from ground
to side to side. In
other words, they
are P or S waves
that hit the surface.
Earthquakes
6. What is the focus
of an earthquake?
7. What
is the epicenter?
6. The
focus is
where rocks first
break and move.
7. The Epicenter is the
point on earth’s surface
directly above the focus.
Earthquakes
8. What is a
seismograph?
8. A seismograph is
an instrument used
to record seismic
waves.
Earthquake Scales
9. What is the
Richter Scale?
9. A Richter Scale
measures the total
energy released by
an earthquake
b) +1 means x32
#29 Quick Quiz- Video Clips
Write answers in complete sentences
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1. What is one of the first signs of a
tsunami?
2 : List two safety measures that Japan
has implemented to reduce the damage
of tsunamis.
Earthquake Scales
10. What is the 10. The
Mercalli
Intensity
Scale?
Mercalli Intensity Scale is a
scale that measures the intensity
of an earthquake. The scale
quantifies the effects of an
earthquake on the Earth's
surface, humans, objects of
nature, and man-made structures
on a scale of I through XII, with I
denoting a weak earthquake and
XII one that causes almost
complete destruction.
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http://videos.howstuffworks.com/hsw/11899
-earthquakes-protecting-structures-fromdamage-video.htm
Locating Earthquakes

http://videos.howstuffworks.com/hsw/9241cleopatras-palace-alexandria-video.htm
Earthquake Zones
11. Where
are the 3
major
earthquake
zones?
11.
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Ring of Fire- is located around
the edge of the Pacific Ocean.
Mid-Atlantic Ridge- this zone is
caused by sea floor spreading
The Mediterranean –Asiatic
Belt- occurs because
continental plates are colliding.
Earthquake Evidence
12. Describe 12. Ground level earthquake
evidence is side to side or up
ground
and down shifts of the ground.
level
The earth has moved mostly
earthquake
slow and steady and is called
evidence
creep
Earthquake Evidence
13. Describe 13. There are 5 descriptions:
landscape  Slide – rapid down slope
movement of soil, debris, &
evidence of
rock
earthquakes
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Scarp – cliff made by uplifted
.
or subsided earth
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http://videos.howstuffworks.com/hsw/9214discovering-plate-tectonics-changingearths-surface-video.htm
Earthquake Evidence
13.
13.
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Fissures – long cracks in soil
or rock
Tsunami – an ocean wave
caused by earthquakes
a) can be 30m high at the shore
Buildings on loose soil have
more damage.
Quick Quiz- Video Clips:
Answer in complete sentences
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1. What is the first sign of a tsunami?

2 : What are two safety precautions that
Japan has implemented to help reduce the
threat of tsunamis?

http://videos.howstuffworks.com/hsw/25886
-tsunami-the-destructive-force-of-tsunamiwaves-video.htm

http://videos.howstuffworks.com/hsw/25893
-raging-planet-history-of-deadly-tsunamisin-japan-video.htm
http://videos.howstuffworks.com/hsw/25895
-raging-planet-japan-responds-to-tsunamithreats-video.htm
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Volcanoes
1. What is a 1. A volcano is any opening in the
earth’s crust that release
volcano?
molten rock.
Volcanoes
2. What is a 2. An opening through which
material reaches the surface
vent?
3. What is a
crater?
. A crater is a hollowed
3
out area in the top of a
volcano
Volcanoes
4. What is the 4. The pipe is a long crack
pipe?
through which magma
moves
5. What is the 5. A chamber with a pocket
magma
of magma.
chamber?
Volcanoes

Label the parts
Volcano Video Part I
http://videos.howstuffworks.com/hsw/19172understanding-volcanoes-part-one-video.htm
Volcanoes
6. What is an
active
volcano?
6. An active volcano has
erupted during the last
century.
7. What is a
dormant
volcano?
7. A dormant volcano has not
erupted for hundreds of years,
but it believed that it has the
ability to erupt.
http://www.geocodezip.com/v2_activeVolcanos.asp
Volcanoes
8. What is an
extinct
volcano?
8. A volcano is considered
extinct if it has not
erupted for thousands of
years.
http://hvo.wr.usgs.gov/volcanoe
s/maunakea/
Volcanoes
9. List the
sequence of
events when
a volcano
erupts?
9. Lava flows out –usually gently
and quietly
2) Then an explosion of debris
occurs. The following are
products of a volcano
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pyroclasts – fragments of
broken rock from a volcano
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ash – hot fine-grained material
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bombs – large molten or
semimolten chunks
http://videos.howstuffworks.com/hsw/6185-mountains-of-fire-an-eruption-video.htm
Volcanoes
10. What are
cinder cone
volcanoes?
10. A cinder cone formed from
ash and cinders in explosive
eruptions. Cinder cones
volcanoes are smaller, coned
shaped, and steep slopes.
Example:
 Paricutín, Mexico
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http://videos.howstuffworks.com/hsw/9221when-earth-erupts-cinder-cone-volcanoesvideo.htm
Volcanoes
11. What are
shield
volcanoes?
11. Shield
volcanoes are from
from lava flow eruptions. They
have broad with gentle slopes.
 An example is
Muana Loa, Hawaii
http://videos.howstuffworks.
com/hsw/9219-when-eartherupts-shield-volcanoesvideo.htm
Volcanoes
12. What are
composite
volcanoes?
12. Composite volcanoes are formed from
alternating layers of lava and pyroclasts.
Characteristics include:
They are explosive and have
lava eruptions
 They are large with steep
slopes
Examples:
Mt. Fuji, Japan & Mt. St.
Helens, Washington
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13. Case study: Pompeii
13.
•79 CE
•Site was not discovered until 1748
•Provided archeologists extraordinary
details about daily life in Roman
Empire
•Some believe that volcano took 2
months to completely bury the town
as people were “found” wearing
winter clothing in the summer, dates
of minted coins and letters
•Populist tourist site in S. Italy
13.
13.
14. Case study: Mt. St. Helen
14.
•Erupted 05/18/1980.
Caused by an earthquake
on 03/20/1980.
•Most deadliest and costly
volcano in US history.
•“Glacier mountain”
•Due to the eruption, at the
top of the mountain is a 1
mile long horseshoe crater.
•Volcano “steamed” until
January 2008
Pompeii:
http://videos.howstuffworks.com/discovery/28991-assignment-discovery-pompeiis-destruction-video.htm
Mt. St. Helens:
http://videos.howstuffworks.com/discovery/7161-mtsaint-helens-powerful-erruption-video.htm
Igneous Rock Features
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Why study? Many features formed
underground by igneous activity are at the
earth’s surface by erosion.
Igneous Rock Features
15. List
intrusive
igneous rock
formations
15. Batholiths,
sills,
dikes, and volcanic
necks.
Igneous Rock Features
16. What are batholiths?
16. Large intrusive igneous rock
body that forms when magma
being forced upward toward
Earth’s crust cools slowly and
solidifies underground.
Igneous Rock Features
17 . What is a dike?
17.Magma that is
forced into a crack
that cuts across layers
and hardens.
18. What is a volcanic neck?
18. Solid igneous core
of a volcano left
behind after the softer
cone has been eroded.
Igneous Rock Features
19. What is a
caldera?
19. Large, circularshaped opening
formed when the
top of a volcano
collapses. Crater
Lake is an example