Transcript What are earthquakes and volcanoes?

What are earthquakes
and volcanoes?
Chapter 6
Lesson 2
SPI’s: Science 7.7.1, Reading 5.1.1,
5.1.2, 5.1.5, 5.1.12, 5.1.13, 5.1.17,
5.1.26, 5.1.30,
In This Lesson We Will Learn:
Why most earthquakes and
volcanoes occur at plate boundaries.
Have you ever heard about a volcano
or an earthquake?
Let’s talk about it…
Where was it?
What were the details?
Why do we need to learn about
Earthquakes and Volcanoes?
Volcanic eruptions and earthquakes can be
violent events. By learning more about them, we
may be able to avoid some of the dangers they
pose.
Think of it like this…
When a fruit pie bakes in the oven, juices and
steam seep up through cracks in the crust. That
is similar to how a volcano forms.
Wouldn’t you want to know when THAT was
coming?
Do you think there is a pattern to the
occurrence of volcanoes and
earthquakes?
To find the answer, let’s do a class
experiment.
• Turn to P. 213 in your text
• Using the earthquake and volcano list on P.
213, we will identify these locations on our
classroom atlas.
• We will use two different colored sticky notes
One color will represent volcanoes, and one color
will represent earthquakes.
Hint: If you are called on to locate one of these
cities, look in the area of the Pacific Ocean.
Experiment continued
Do you see a “ring” around the Pacific Ocean?
Does anyone know what that ring is called?
The Ring of Fire!!!
Why is this area called,
“The Ring of Fire”?
Answer
Volcanoes and earthquakes are very common
along the Ring of Fire.
Why are volcanoes and earthquakes
more common around the
Ring of Fire?
Hint… it has something to do with the
movement of Earth’s plates…
Answer
Most volcanoes and earthquakes occur near
plate boundaries; for example, around the edge
of the Pacific Ocean.
Ring of Fire
Let’s jump ahead to P. 220 in your text and read
about the Ring of Fire.
Vocabulary
Get out your Science journals...
It’s time to “get smart”!!!
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Earthquake
Epicenter
Fault
Focus
Magma
Seismic waves
Vocab. Cont…
• Earthquake: violent shaking of Earth’s crust as
built–up energy is released
Vocab. Cont…
• Epicenter: point on Earth’s surface directly
above the focus of an earthquake
Turn to page 216 in your text. Look at the
graphic titled, “Seismic Waves”. Notice the
epicenter labeled on the second graphic.
Vocab. Cont…
• Fault: crack in Earth’s crust along which
movement takes place
The San Andreas fault extends almost
the full length of the state of California!!
Vocab. Cont…
• Magma: melted rock below Earth’s surface;
called lava at the surface
Is this lava or magma?
Vocab. Cont…
• Seismic waves: waves of energy sent through
Earth’s crust when plates move suddenly
Turn to page 216 in your text. Look at the
graphic titled, “Seismic Waves”. Notice the
seismic waves labeled on the second graphic.
I need a volunteer, please
We’ll take turns reading pages 214 and 215.
Who would like to go first?
(Remember, when we read, we pay attention to what
we are reading, and we read with expression and
enthusiasm!!!)
Let’s be detectives…
Who can go back and find two words with the
root – verge?
Who can tell me what verge means?
Verge means…
Verge comes from the Latin word vergere, which
means “to turn”, or “to bend”
The prefix con – means together
The prefix di – means two
Now, let’s be detectives and figure out (using our
new clues) what converge and diverge mean.
Remember:
In This Lesson We’re Learning:
Why most earthquakes and volcanoes occur at
plate boundaries.
Question
What information does a seismograph record?
Answer
The strength of seismic waves moving through
Earth’s crust and along the surface.
(you’re so smart!!!)
Question
How is a diverging boundary fault created?
(c’mon man, think!!!!)
Answer
At diverging boundaries, stress builds up
between blocks. Eventually, the rock breaks, and
one block moves down a sloping crack.
(Remember, “di” means two, and “verge” means
“to turn” or “to bend”)
Let’s try another one…
At what type of fault does force squeeze rock,
causing it to break and causing the rock on one
side of the fault to move up while the rock on
the other side moves down?
…you know this!!
Answer
Fault at converging boundaries
Way to go!!!!!!!
Let’s continue reading P. 216
I need a volunteer to begin reading the
paragraph titled “Earthquakes”
*While your classmate is reading, listen for the
meanings of the words, “magnitude” and
“intensity”. When you hear it, raise your hand!!!
Compare and Contrast
It’s Science journal time…
In your journal, compare and contrast how the
measurements of an earthquake’s magnitude
and intensity are alike and different. Refer to
your text of you need help.
Learning about earthquakes is so cool!!!
Let’s continue reading P. 217
This time; while your classmate is reading, I
want you to figure out why surface waves cause
great damage.
Answer
Surface waves make the ground swell and roll.
Question
Would an earthquake that measures 7.7 on the
Richter scale cause blocks of rock to shift a lot or
a little?
A lot!!!
Remember… the higher the
number, the greater the damage!
Let’s Talk Volcanoes…
Where does the word “volcano” come from?
(You’re “gonna” love this…)
Answer
The word volcano comes from the name of the
ancient Roman god of fire, Vulcan.
(Pretty cool, eh?)
I need a volunteer, please…
We’ll take turns reading PP. 218 and 219.
Remember, when you’re reading to the class,
pay attention to what you are reading, and use
expression.
Be sure to follow along as your classmate reads
because YOU could be the next one called on to
read!!
In Your Science Journals
Compare and Contrast:
How are a crater and a chamber alike and how
are they different?
Classify:
If you saw a volcano, what clues would tell you
what type of volcano or volcanic cone it was?
Way To Go!!!
Now you know why most earthquakes and
volcanoes occur at plate boundaries!!!