Download File - Mr. McCabe

Earthquakes are measured by 2 scales. One scale measures
the DAMAGE an earthquake causes and the other measures the
MAGNITUDE or size of an earthquake created by the seismic
waves. The two most popular scales are called the Richter Scale
and the Mercalli Intensity Scale.
The first is called the
RICHTER SCALE. The
Richter Scale measures
the size or MAGNITUDE
of an earthquake. It
measures the maximum
amplitude of the “S”
waves created by an
earthquake.
Each step is 10 times the
magnitude and releases
30% more energy.
Earthquakes are measured by 2 scales. One scale measures
the DAMAGE an earthquake causes and the other measures the
MAGNITUDE or size of an earthquake created by the seismic
waves. The two most popular scales are called the Richter Scale
and the Mercalli Intensity Scale.
The other Scale is called
the Mercalli Scale
The Mercalli Intensity Scale
measures the DAMAGE
done by an earthquake.
Why is this scale not as
accurate as the Richter
Scale?
What has happened here? Mercalli?
What has happened here? Mercalli?
• Chino hills (30 miles from LA) 6.4 Ricther.
DAILY QUESTIONS #10
1. Name the “description” the “earthquake effects” and the
“frequency” of a magnitude 7.3 earthquake.
2. Name the “description” the “earthquake effects” and the
“frequency” of a magnitude 4.5 earthquake.
3. What would you expect to feel during a Mercalli scale
rated Earthquake of a IV (4)?
4. What would you expect to feel during a Mercalli scale
rated Earthquake of a X (10)?
5. Describe the motion of a raleigh wave.
6. Describe the motion of a love wave.
7. Put the following in order from fastest to slowest. Love
wave, primary wave, secondary wave.
8. Please have a ½ sheet of paper out for your 8.2 quiz.
8.2 Quiz
1.Get out a half sheet of paper for your
quiz.
2.WRITE IN COMPLETE
SENTENCES!!!!
3.Turn your paper over when you are
finished.
8.2 Quiz
1. Define Surface waves
2. Which waves are faster P waves or S waves (complete
sentence!)
3. What are instruments that used to measure earthquake
waves?
4. According to the book, P waves are also called
_________ waves.
5. Seismogram shows this type of wave(s)
a) P waves
b) S waves
c) surface waves
6. Define S waves.
7. List the 2 categories of seismic waves.
d) All
LOCATIN’ THE SHAKIN’!!
Seismologists locate earthquakes by
measuring the time between the P and S
waves on a seismogram, produced by a
seismoGRAPH.
After a seismograph "feels" an earthquake,
scientists compare the time difference of
these waves to figure out how far away the
earthquake is.
EARTHQUAKES!
• How do we calculate
the magnitude (richter
scale) of an
earthquake?
• Pieces of information
needed:
– Time (seconds) between
when the P waves and S
waves arrived. Called
“LAG” time.
– Amplitude of the tallest S
wave, measured in
millimeters.
– ABILITY to read charts
C.O. – SWBAT understand the richter scale magnitude of Earthquakes and be
able to locate Earthquakes using triangulation.
L.O. – SW practice how to read and calculate nomograms and triangulation.
DAILY QUESTIONS #11
1. How many seismographs do we need to locate the
epicenter of an earthquake?
2. Describe how a convection oven is better than a regular
oven.
3. What type of waves are P and
S waves? (not body/surface)
4. The map to the right shows the
Effects of an earthquake based off of
the Mercalli scale. Describe the
differences (damage) between the
4 zones shown.
5. What city was the closest to the
epicenter?
6. Why are 9’s so far away from the epicenter?
LOCATIN’ THE SHAKIN’!!
• Time between P and S waves =
• Amplitude of the highest S wave =
LOCATIN’ THE SHAKIN’!!
• Lag time converted to
distance in km
LOCATIN’ THE SHAKIN’!!
• Distance and amplitude
gives us MAGNITUDE.
LOCATIN’ THE SHAKIN’!!
Because we know the
relative speeds of
earthquake waves, we
can measure the time
between the P and S
waves to understand
how far away the
Earthquake occurred.
LOCATIN’ THE SHAKIN’!!
We then can measure the AMPLITUDE of the S
wave to then calculate the magnitude of an
earthquake wave.
LOCATIN’ THE SHAKIN’!!
It takes at least three seismographs to locate an
earthquake’s epicenter.
One seismograph can
only tell how far away it is
from that seismograph.
By measuring the S-P
wave times at 3 or more
stations, these circles can
be drawn around each
station (seismograph) and
where they meet indicates
the earthquake location.
Today you will be calculating
distance and the radius of
circles of 3 overlapping
seismograph stations.
READ THE DIRECTIONS!
USE cm DO NOT USE cm
ON COMPASS!!
Color each set of circles the
same color so you don’t get
confused. I.E. EQ1 = blue.
FOLLOW THE
DIRECTIONS!
Hints on drawing circles.
LAB - Finding the Magnitude and
Epicenter of an Earthquake
Richter Scale
Moment Magnitude Scale
#’s used
1-10
1-10
Easy to figure out
YES
NO
Energy Released per whole # on the scale (ex:
from a 1 -2)
Each step 10x greater
Each step is 32x greater
Energy released from a Mag. 3 to 4
4 is 10x greater than 3
4 is 32x greater than 3
Energy released from a Mag. 3 to 5
5 is 100x greater than 3
Energy released from a Mag. 6 to 7
7 is 10x greater than 6
Energy released from a Mag. 6 to 9
5 is 1024x greater than 3
7 is 32x greater than 6
9 is 1000x greater than 6 9 is 32,768x greater than 6
DAILY QUESTIONS #12
1. Use the following terms and place them in outline format.
Choose the order you feel is the most logical. Use your
notes and your group to discuss the best flowing outline.
You may need to write your own descriptions.
P waves
1-10
Love waves
I-IIV
Richter scale
x10
Surface waves
mercalli scale
Example of outline format:
Transverse waves
1. Main idea or theme
Damage
A. Sub-idea or theme
Types of earthquake waves
a) Another sub idea or theme
B. Second Sub idea
Raleigh waves
a) Etc..
S waves
b) Etc…
2. Another main idea or theme
Body waves
A. Etc..
Longitudinal waves
B. Etc…
a) Etc…
Magnitude
Parts of a Seismogram Review
Amplitude
P waves
S waves
Interpreting the Seismogram
Amp
1.
Eureka, CA;
0s
P wave arrival = ____________
S-wave arrival = ____________
49 s
49 s
P-S wave interval in s = ___________
mm
Amplitude = 285
__________
P
S
Interpreting the Seismogram
Now do the other 2 on your own
Elko, NV
Las Vegas, NV
478
1. Eureka, CA = _____________km
702
2. Elko, NV = __________km
624
3. Las Vegas, NV = _________km
Getting the
Distance to
the Epicenter
Calculating the Magnitude using a
Nomogram
1. Eureka, CA = _____________km
478
2. Elko, NV = 702
__________km
624
3. Las Vegas, NV = _________km
Richter Magnitude =
7.1
_________________
C.O. – Students will explore earthquake effects on the crust of the
earth and the rock layers associated with it.
L.O. – Students will practice reading nonograms, seismograms and
use them to compare the effects of earthquakes.
DAILY QUESTIONS #13
Please collect one of the half sheets from the front. These will need to be
ATTACHED to your notebook (taped or glued in) by Monday. NO I do not have
stuff you can borrow right now to do it. Use the 2 graphs to answer the following
questions. You will be using these graphs many times so if you write on them,
write lightly so you can erase and use over and over. These are for reference.
1. How far away is an EQ with an SP lag time of 55 seconds?
2. If an EQ happened 400 kilometers away, how long should I expect
the lag time to be?
3. If an earthquake was 100 kilometers away and had an amplitude of
20mm, what would its estimated magnitude be?
4. If a seismogram had an S wave amplitude of 100mm and was a
magnitude 5.0, estimate about how far it was away from that
seismograph station.
5. An earthquake lag time was about 60 seconds. The S waves
recorded had an amplitude of 5mm. What was the magnitude of that
Earthquake?
6. A seismogram had an amplitude of 200mm and an estimated
magnitude of 7.0. About how far away was that Earthquake and
estimate about how long lag time between P and S waves would be.
Triangulating the Epicenter
478
1. Eureka, CA = _____________km
702
2. Elko, NV = __________km
3. Las Vegas, NV = _________km
624
500
600
700
Earthquake # 2
Now that you are an expert on finding the magnitude
and epicenter of an earthquake, work to calculate both
for our second earthquake.
This work and the lab questions will be due at the
beginning of class tomorrow.
DAILY QUESTIONS #14
1. Describe a reason why it is very difficult to predict
earthquakes.
2. Name the 2 types of earthquake waves
3. Which are body waves?
4. Which waves are Surface waves?
5. If a seismogram had an S wave amplitude of 80mm
and was a magnitude 5.0, estimate about how far it
was away from that seismograph station.
6. An earthquake lag time was about 50 seconds. The S
waves recorded had an amplitude of 5mm. What was
the magnitude of that Earthquake?
7. A seismogram had an amplitude of 100mm and an
estimated magnitude of 6.0. About how far away was
that Earthquake and estimate about how long lag
time between P and S waves would be.
DAILY QUESTIONS #15
1. Based on the map and your mercalli scale, what is
the highest level of destruction that happened here?
2. Use the Mercalli scale and the map to describe what
3 other cities felt.
3. What is the magnitude
of this earthquake?
4. When did this earthquake
occur?
5. Using your S-P chart
and your nomogram, figure
out the magnitude of an
Earthquake that was 60s
away from a seismograph
and had an amplitude of
100mm.
Homework calendars!
• Write this down…
• EQ location paper due tomorrow!
• QUIZ on how to read an S-P lag time chart,
and an earthquake nomogram chart to figure
out distance, magnitude and amplitude of an
earthquake.
• Students should also know how to triangulate
earthquakes.
C.O. – Students will understand how to read an S-P lag chart, an earthquake nomogram to
calculate earthquake characteristics.
L.O. – Students will practice reading nomograms and S-P lag chart and use a compass to
triangulate epicenters.
DAILY QUESTIONS #16
1. How far away is an earthquake if it took 35 seconds
to get there?
2. If I have a lag time of 40 seconds, how far away did
the earthquake occur.
3. How many seismographs do I need to find the
epicenter of the earthquake?
4. How far is an earthquake away if it was 5.1 on the
richter scale and had an amplitude of 100mm?
5. An earthquake had a magnitude of 7.0 and an
amplitude of 500. How far away was the earthquake?
6. An earthquake occurred 200 km away with a
magnitude of 5.9, what was its amplitude?
7. An earthquake occurred 60 km away and had an
amplitude of 200 mm, what was its magnitude?
Earthquake quiz!
• Please have only a pen and or a pencil on
your desk. Everything else off. You will
need either your ID card or a ruler, or
something you can use to draw straight
lines.
9.1 (next left hand page)
• Words: continental drift, pangaea, Mesosaurus,
• Questions: 1-5
• If you are not finished with your Earthquake
paper, you can finish that now but it is due
today.
• If you are finished, your classwork for today is
9.1
Evidence for plate tectonics
Draw and
Describe the
Layers of the earth.
We live on egg shells
• The earth is made up
of many layers. Just
like an Egg.
• An egg has many
layers
Crust
Cold
THICK JELLY
Hot
HEAT!
HEAT!
Convection
Currents
LIQUID
HEAT!
HEAT!
SOLID
Responsible of
MAGNETIC FIELD
Flash cards for quiz
• You will be having a quiz on the following words
tomorrow.
• Please make the following words into
flashcards so you can study them.
• DO NOT GET THEM FROM THE BACK OF
THE BOOK. The chapter and section of the
book are listed next to the word, where you can
find them.
Flash cards for quiz
•
•
•
•
•
•
•
•
Crust (8.4)
Mantle (8.4)
Lithosphere (8.4)
Asthenosphere (8.4)
Moho (8.4)
Pangaea (9.1)
Mesosaurus (9.1)
Continental drift (9.1)
Evidence for plate tectonics
Describe, in your
own words, what
plate tectonics is
all about.
C.O. – Students will understand how the interior of the earth result in movement of tectonic
plates.
L.O. – Students will practice read and discuss and take notes on the layers and tectonic
plates
CAUSE – mantle convection
EFFECT – moving plates