Transcript Earth and the Moon - Nutley Public Schools

What is happening in this
photograph??
What do volcanic eruptions
reveal about the earth’s
interior??
What do you think the darker
material floating on the molten
lava is??
 Objectives:
› Describe what happens during an
earthquake
› Explain the difference between an
earthquake’s focus and epicenter
› Compare and Contrast the three
types of waves produced by
earthquakes
 This Just In ……
› Imagine you are listening to the radio
when the announcer says that a 5.8
earthquake has occurred in Alaska.
› How do earthquakes happen??
› What does the 5.8 mean??
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Movements of the
earth’s crust that
occur when ______
_________and release
stored _________
Energy quickly travels
out in ________ from
the point of breakage
Energy can ______ and
________ rock and soil
Most occur at depths
less than ____________
because the rocks are
brittle
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Most earthquakes
result from
movements of the
earth’s crust along
___________
Faults are __________
in the earth’s crust
The 2 sides move in
_________ _______
and earthquakes
occur
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As the 2 sides of a
fault move past
each other,
sometimes the rocks
________, _______ and
become __________
Tremendous ________
builds up in these
areas

______ _____ – amount
of stress a material
can absorb
› Example – rubber
band stretched too
far
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When rocks are
strained beyond
elastic limit – _______
and ________ past
each other
Huge amount of
__________ released.
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As rocks break and
move, __________
_______ is transformed
into _______ _________
_______ ________ – the
vibrations produced
by earthquakes
3 Types:
› ____________
› ____________
› ____________
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P Waves – _________
seismic waves
_____________ - the
material through
which the wave is
travelling moves in
the _________
direction as the
wave
____________________
_______the earth in
direction of the
wave
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S Waves - second
waves to arrive at a
given point – _____
_________
__________ – material
moves at ______
________to the wave
direction
Like the up-anddown movement of
a rope

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____________– when
P and S waves arrive
at earth’s surface
Cause the earth’s
surface to __________
____________________
____________________
____________________
Cause the __________
damage during an
earthquake

Earthquakes movie

_______ – area along a
fault where _________
______ ______________ –
where earthquake
begins
› Seismic waves travel
out in __________
from the focus

___________ – point on
earth’s surface directly
__________________ –
strongest shakes felt
here
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________________ detect and record
seismic waves
Have a pen attached
to a weight and a
sheet of paper on a
revolving drum
Seismic waves cause
the pen to _______ and
record a wavy line on
paper
_________ of the peaks
indicates the _________
of the earthquake

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P, S, and L waves
travel at _________
_________
So, they reach a
seismograph at
__________ _________
The difference
between the arrival
times of the waves
helps scientists find
the _______________
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Calculated distance
to the epicenter
becomes the ________
of a circle that is
plotted on a map
Epicenter lies
______________ on the
circle
Plotting circles from
___ ____________
_______ _________
pinpoints the
epicenter – why do
you need 3 stations??

_______ _________–
compares the size of
earthquakes using data
from seismograph
stations
› Each increase of _____
magnitude number
equals an increase of
______ in ground motion
› A magnitude 7
earthquake causes 10
times more damage
than a magnitude 6
and 100 times more
damage than a
magnitude 5
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________ ________–
measures the effects
of an earthquake on
›
›
›
›
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________________
________________
________________
________________
Data gathered from
people who have
experienced the
quake are used to
determine an intensity
value for their location
Comparing earthquake scales
 Textbook page 136
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Most of the world’s
earthquakes occur
along or near the
edges of ________
______________
At these spots, ______
is the greatest
3 Major earthquake
zones:
› 1. ________________
› 2. ________________
› 3. ________________
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Accounts for ______ of
world’s seismic activity
Goes all the way
around the _________
_________
Includes east coast of
Asia and west coasts
of North and South
America
Active spots in the U.S.
› __________________
› __________________
Hypothesis – ________________ __________
is being made along the mid-Atlantic
ridge
 This causes many earthquakes
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_____________
_________ are
colliding

Causes very
destructive
_____________
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Small number of
earthquakes occur
far from plate
boundaries (strong)
› ___________________
___________________
› ___________________
___________________

Even quiet parts of
earth can conceal
large amounts of
____________
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1983 – Coalinga, Ca
(between LA and SF)
Magnitude __________
earthquake
Surprised scientists:
› __________________
› __________________
› __________________
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Team of scientists
studied what
happened
Found several faults
___________ beneath
They were hidden
inside of __________
in the earth
The determined
these faults are
______ very active
1. Explain what causes earthquakes.
 2. What is the difference between an
earthquake’s focus and epicenter?
 3. How do the 3 types of seismic waves
differ? How are they similar?
 4. Would using 4 seismograph stations to
locate the epicenter of an earthquake
be any more accurate than using 3?
Explain.

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Page 139 in Textbook
 Objectives:
› Describe some features produced by
earthquakes
› Discuss factors that determine
earthquake damage
› Explain what causes tsunamis
› Make Inferences about ways to build
structures that could withstand major
damage from earthquakes

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Earthquake
evidence is
sometimes
preserved in ________
or ____________
changes to the
ground
Strong earthquakes
leave _________
evidence
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At some faults
changes are _____ but
________________ – no
earthquakes
____________ – slow,
continuous, steady
motion
Creep rate of 1
cm/year – ground
levels would be
displaced by 1 meter
after __________
Can break structures
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Powerful
earthquakes can
cause ____________
damage
____________
earthquake of 1964
– ______ magnitude
Upheaval of
>260,000 square km
of ground
___________ moved
sideways!

Earthquakes
affect poorly
compacted
sediments more:
› __________
› __________
› __________
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Rapid down slope
movements of ________,
________, and _________
Can occur on a _______
or far away
Large sections of
mountain may ________
and race downward
Some continue for
____________, destroying
all in their paths (homes
and roads)
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Sudden earth
movements that
_________ ________
Height depends on
the _____ of material
uplifted and the
___________ and
___________ of uplift
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Long ________ in rock
or soil
May extend for
_______ _____________
If fissures occur on hill
or mountain –
massive ____________
can occur


____________ of
epicenter to
______________ area
Moderate quake in
a crowded city
causes _________
damage than a
large quake in a
desert

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
_______ ___ _________
where structures are
built affects amount
of damage
Soft, wet, loose soils
can ___________
seismic waves
Buildings on more
solid ground have
better chance of
survival
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Building ________ and
_____________ affect
damage
________ __________
buildings may move
with and withstand
ground motion
Brick and cement
may ________ and
_____________
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__________ – an ocean
wave caused by
________________
__________ water –
tsunamis are low and
fast-moving
__________ water –
they slow down and
increase in height (30
meters)
Few structures survive
a large tsunami
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Past – changes in
animal behavior and
well levels
Now – seismologists
look at
› __________________
› __________________
› __________________
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1981- scientists predict
a quake is likely in the
_____ _______mountains
within ______ years
1988 and 1989 –
moderate quakes
identified as ___________
1989 – devastating
earthquake in _______
___________

If you live near an active fault – should
have an earthquake _______ ________
› What to ______ during quake
› Where to ________ after quake
› How to ______________ if phones don’t work

In earthquake-prone areas – strict
_________ ___ _________ laws are in place
1. What are some changes caused by
earthquakes?
 2. What factors determine the amount of
damage caused by an earthquake?
 3. Describe the hazards you might face if
an earthquake struck while you were:

› asleep in bed
› standing next to a tall building
› at the beach
› skiing

Earthquake Webquest
 Objectives:
› Describe how volcanoes form
› Explain why volcanoes erupt
› Compare the 3 main types of
volcanoes
› Make a model of the structure of a
volcano
 Pressure Is Mounting
› What happens when you blow up a
balloon or inflate a tire and put in too
much air?
› What happens when heat and pressure
build up in a closed space and the
pressure is suddenly released?
› How might these pressure situations be
similar to a volcano that is about to
erupt?
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Any opening in the
earth’s crust that has
________ _______ ______
Also, the mountain
that builds up from
_________ _________
Examples:
› _______ – Japan
› ______________ –
Washington state
› _____________ - Sicily
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________ (molten rock)
is under great ________
deep inside earth
Magma forms deep
pockets called
________ ___________ in
some places
If the __________ and
_________ are great
enough, magma will
force its way up
through earth’s crust
The more heat and
pressure acting on
magma – the more
likely magma will force
its way to the surface
 _________ – magma
that reaches the
earth’s surface
 __________ – when lava
or other volcanic
materials reach earth’s
surface
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___________ – have
erupted in the past
century
___________ –
haven’t erupted in
hundreds of years
___________ –
haven’t erupted in
thousands of years
Eruptive life may
span _________ __
________ ___ ______
Mount Popa Myanmar
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_______ ___________ –
formed from large
pockets of magma
When magma is hot
or powerful enough,
it makes its way
toward the surface
through ________ in
the ________
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________ – long, nearly
_______ ________ in the
crust through which
magma moves
Can be thousands of
meters long and only a
few meters wide
Magma travels
through the pipe until
it reaches a ________
on earth’s surface
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__________ – steep,
hollowed-out area
surrounding a vent
at the _______ of a
volcano
Usually forms after a
very _____________
eruption
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________ – opening
through which all
volcanic material
________ ____ _______
Common at the tops
of volcanoes, but
may also be _______
___ ________

Eruptions can be:
› _____________________
_____________________
› _____________________
_____________________

This is determined by:
› __________________
› __________________
› __________________
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_________ of lava
that flows from a
vent
Stream can be
_______ or spread out
Some lava flows can
reach speeds of
_________________
Lava cools and
hardens as it moves
Example - __________
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Explosive volcanoes
give off ___________
_________
Debris is identified by
____________
› Dust – size of flour
grain
› Ash
› Cinders
› Bombs - > 64 mm
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Produced by
different types of
volcanic eruptions
and explosions
Named for its shape
or structure:
› __________________
› __________________
› __________________
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Form from the
products of _________
_____________
Ash, cinders, and
other debris mound
up around the vent,
___________ __ ______
Are ________ sloping at
the top and _________
sloping at the base
Usually form from ____,
____________ magma
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Have ______, shield
like shapes
Lava is _______ and
______ ______ away
from the vent
As it cools down, it
becomes thicker,
slows down and
collects.
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Contain alternating
layers of _________
_____ ____ _______
Usually formed from
_______ ________ of
eruptions
Have ______ tops but
gently ___________
bases
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Most earthquakes
and volcanoes
occur along _______
______________
Volcanic activity
can often produce
___________________
As magma moves
up, it may _________
rocks or ___________
overlying crust
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Encircles ______________
Major zone of both
_____________ and
_______________
Ocean plates are
______________ and
volcanoes occur in long
chains
One major chain runs
along the west coasts
of _______ _____ _______
_____________
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Earth’s _____________
volcanic zones
Plates are moving apart
forming cracks called
___________
As magma rises through
rifts, the _______________
Lava builds up forming
underwater ___________
__________ is formed
from volcanoes that
have risen above the
surface
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Develop in parts of
the earth’s mantle
that are _______ _____
They can be _______
from plate boundaries
As the hot spots melt
the surrounding rock,
the rock changes to
_________ and rises to
the surface
_________ ________ are
formed over a hot
spot
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________ __________ is
the only active
volcano on the
European mainland
It is located just
outside _______,
_______
It last erupted in ____
Most destructive
eruption was on
August 24, AD. 79

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
Most people
probably didn’t
know that the
mountain was a
volcano
It hadn’t erupted in
_______________
But there was a
________ earthquake
17 years earlier

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Eruption rained hot
ash, mud, and stones
on the residents of
_____________
Many people did not
survive – _______ ______
Town disappeared
completely under
_____ __________of ash
and stone
Wasn’t rediscovered
for ___________ years
How does life develop on
molten rock?
 Moisture from _______ and
______ react chemically with
exposed _________
 Over time, ________ develops
 Wind, waves, and birds scatter
________, ______________ and
_________
 ________ and _________ appear
and break down rock
 Ocean currents bring _________
life
 Eventually there will be a
____________ of plants and
animals

Surtsey, Iceland

Sophisticated devices
can monitor:
› __________
accumulation
› increased __________
activity
› changes in
________________
› gas ____________

Advances in
photography and
satellite imaging
1. What is a volcano? How does it form?
 2. Explain the differences between shield
volcanoes, cinder cones, and composite
volcanoes.
 3. Volcanic activity has been known to
trigger tsunamis. How is this possible?
 4. Draw a general diagram of a volcano.
Label its main parts.

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Volcano Webquest

Review sheets – quiz grade