Download Earthquakes! - Earth Science @ POB

Warm-up: Breaking News!
• PREPARE FOR AN EARTHQUAKE!
• Imagine that you have just received news that
Charlotte is preparing for an earthquake. If you
had to prepare an emergency kit, what would
you include?
Earthquakes!
SWBAT identify the anatomy of an earthquake
SWBAT relate earthquakes to plate
boundaries.
Warm-up: Breaking News!
• PREPARE FOR AN EARTHQUAKE!
• Imagine that you have just received news that
Charlotte is preparing for an earthquake. If you
had to prepare an emergency kit, what would
you include?
Complete Reflection when done with warm up
Follow-up: Did you think of these things?
• First aid kit and instruction booklet
• Plastic tarp or a small tent
• Emergency ("space") blankets and one sleeping bag for each family
member
• At least one gallon of bottled water per person, per day. For a 3-day
supply, that adds up to three gallons of water per person
• Enough canned or dried food for 3 days
• Can opener
• Flashlight (easily in reach)
• Battery-powered radio
• Spare batteries for everything (stored separately in waterproof bags)
• Toilet paper, soap, toothpaste and toothbrushes, and other personal
supplies
• Multi-purpose dry chemical (Class ABC) fire extinguisher
• Any important medicine and supplies for infants, elderly people, and
others with special needs
North Carolina
This map represents seismic activity in North Carolina from 19002006. The pink dots represent earthquakes. Make 2 observations
and one inference about this map.
Guided Notes
What is an earthquake?
• An earthquake is the shaking of the ground due to
the movements of tectonic plates
• Earthquakes occur at different plate boundaries
What happens during an earthquake?
• Foreshock: any of the usually minor tremors
commonly preceding the principal shock of
an earthquake
• Earthquake!
• Aftershock: smaller earthquakes which are
generated by the continued movement of
plates and other materials after the main
shock
Parts of an Earthquake
The focus of an earthquake is the point WITHIN the
Earth where the earthquake starts. It is the place
below the earth’s surface where the rocks tear,
come apart, or collide.
Parts of an Earthquake
The epicenter is the location on the EARTH’S
SURFACE directly above the focus. Surface
waves move outward from the epicenter.
Parts of an Earthquake
The fault is the break in the
crust where the earthquake occurs,
between two blocks of rock that
have moved past each other.
Types of Faults
Strike-Slip, Reverse, Normal
Each fault occurs at a different type of boundary!
Convergent = Reverse
1.
Where does this occur?
At a Convergent Boundary
1.
What is it?
A reverse fault happens when
two blocks of crust are
pushed up against each
other and they slide
vertically
1.
Type of Earthquake?
These types of earthquakes
are usually strong and
deep
Divergent = Normal
1. Where does this occur?
At a Divergent Boundary
2. What is it?
A normal fault occurs when
two blocks of crust are
pulled away from each
other and slide vertically
3. Effect on Earthquake?
This type of earthquake is
usually weak and
shallow
Transform = Strike-Slip
1. Where does it occur?
At a transform Boundary
2. What is it?
A strike-slip fault is when
two blocks of crust slide
past each other
horizontally
3. Effect on Earthquake?
These types of
earthquakes are
moderate and shallow
SEISMOGRAPH
Instrument
used by
scientists to
measure
Earthquakes.
What do we use to measure
earthquakes?
Richter Scale – a scale from 1 – 10 that tells the
magnitude (intensity) of an earthquake
EARTHQUAKES
An aftershock is a smaller earthquake that occurs after a previous
large earthquake in the same area (the main shock).
Let’s take a look at the U.S!
In which state do most earthquakes in the United States take place?
Why does California see so
many EQs?
• The San Andreas Fault!
Elastic Rebound Theory
Why do earthquakes occur?
Along a fault, energy
builds up in a rock
until it breaks and
releases energy. This
rock is ELASTIC
energy.
This release of
energy causes an
earthquake.
What Causes Earthquakes?
• As tectonic plates
push, pull or scrape
against each other,
stress builds up along
faults until the rocks
finally move
• The elastic rebound
theory is the main
cause of earthquakes
Elastic Rebound Theory
The gradual buildup, and release of
stress and strain, between tectonic
plates which leads to earthquakes
HAITI
History of EQs
• Watch videos to learn about examples of real
earthquakes
• Filling in table with details about each EQ
• Head up, Eyes up, Pen in hand, Listening
silently
Independent Practice
• Plate Tectonics Choice Board
• Three activities minimum
• Extra credit for additional boxes
• Use all resources available
• Textbook, vocabulary list, warm ups, guided
notes, internet, peers
• Take 1 minute and read each assignment
• Turn to your partner & tell them what activities you
might choose
Exit Ticket
1. What is an epicenter?
2. What is the elastic rebound theory?
3. Where is the focus in relation to the epicenter?
4. Draw & label a diagram of the three types of faults.
Earthquake Energy!
Extension
Magnitudes and Energy of Earthquakes
Annual Numbers of EQs
What’s the message?
MOST of the energy is released by around 20 magnitude-7 and larger EQs
every year.
Seismic intensity is affected by rock type.
Amplitude of oscillation
Form a hypothesis about how would you expect the houses to react
during an EQ.
Seismic intensity is affected by rock type.
Amplitude of oscillation increasing