analyzing data, graphing, predicting, modeling, and hypothesizing
(A) Science as Inquiry Develop descriptions, explanations,
predictions, and models using evidence.
(A) Science as Inquiry Thinking critically and logically to
make the relationship between evidence and explanations.
(A) Science as Inquiry Use mathematics in all aspects of scientific
(B) Physical Science Transfer of energy via mechanical motion.
(D) Earth and Space Science Structure of the Earth system -
The solid earth is layered with a lithosphere; hot, convecting
mantle; and dense, metallic core.
(E) Science and Technology Understandings about science and
technology - Science and technology are reciprocal.
(F) Science in Personal and Social Perspectives Natural hazards
- Internal and external processes of the earth system cause natural
hazards, events that change or destroy human and wildlife habitats,
damage property, and harm or kill humans.
(F) Science in Personal and Social Perspectives Risks and benefits
(F) Science in Personal and Social Perspectives Science and
technology in society
(G) History and Nature of Science Nature of science - It is
part of scientific inquiry to evaluate the results of scientific
investigations, experiments, observations, theoretical models,
and the explanations proposed by other scientists.
(G) History and Nature of Science History of science - Tracing
the history of science can show how difficult it was for scientific
innovators to break through the accepted ideas of their time to
reach the conclusions that we currently take for granted.
Eleven 50-minute sessions or five 50-minute and three 90-minute
are one of the most powerful natural forces that can disrupt our
daily lives. Through careful study, geologists are slowly learning
more about such questions as these:
Why do earthquakes occur?
Why do some locations such as California and Japan receive so
Can we design a city to better withstand an earthquake?
Can we stop earthquakes before they occur? Should we try?
assume the role of a seismologist while working on several self-guided
activities to help them think like a geologist. Some of
the activities depend on material learned form previous activities;
therefore, completing the activities in order will help students
to understand each activities better. After developing an
understanding of how seismologists collect and analyze data and
how earthquake epicenters are located, students
demonstrate an understanding about the three types of earthquake
stress that occur in the crust and associated fault deformations.
distinguish between the three categories of seismic waves.
analyze and interpret data to locate the epicenter of an earthquake.
draw conclusions about the inside of the earth.
develop a model of the earth and evaluate the model for its strength
think critically about scientists role in society.
Students print out a scavenger hunt worksheet. By accessing
a variety of listed websites, students are capable of completing
the scavenger hunt. Students will learn that searching results
in a strike-slip fault, tension results in a normal fault, and
that compression results in a reverse fault. Students will
also develop an understanding of how P (primary), S(secondary),
and L(long or last) waves travel.
to the crossword puzzle can be found here: Earthquake
understanding of this information is important background information
for the other activities, encourage students to utilize a dictionary
or the definitions link.
a Quake: Students will view simplified versions of eight
seismograms from eight locations around the world. All eight seismograms
were caused by the same earthquake, though the epicenter of this
quake is not revealed (students discover it in the later activity
Locating an Epicenter) Students will answer questions regarding
these seismograms. Questions focus on identifying the three main
types of seismic waves (P, S, and L), observing that not all cities
received all three wave types, and beginning to hypothesize why
some cities did not get all of the waves.
Students will probably need help understanding the seismograms.
Make sure they clearly understand these points:
1) All recorded waves for all eight locations came from one earthquake
(the quake originated in the Asian side of the Pacific Ocean).
2) Although the seismic waves that created the zig-zag lines left
the epicenter at exactly the same moment, they arrived at different
times in different locations. Cities that were close to the epicenter
received waves first; distant cities received waves last.
3) The first wave to arrive is always the Primary (P) wave, (unless
the P wave is deflected and never arrives at all).
4) Each city started recording its seismogram at the exact moment
the P wave first arrived there. Thus each city started recording
at a time of day different from any of the other cities.
For example, if the quake began at 12:00 p.m., Tokyo received
the first P waves at about 12:05 (and the first S waves at about
12:09), but Rio received these same P waves at about 12:20. (In
this activity, students can determine for themselves which cities
are nearest the epicenter.)
What should the student learn in this activity?
The earthquake created at least three types of waves:
1) A first wave (Primary, P) that hit suddenly but with only minor
vibrations, and then slowly died out.
2) A second sudden set of small vibrations (Secondary, S) that
slowly died out.
3) A final set of very large vibrations (Last, L) that pulsated
by growing larger, then smaller, then larger, etc.
Students should also learn that some cities which are relatively
near each other (compared to the size of the earth) receive very
different waves. One city can receive P, S, and L waves, while
a nearby city receives only L waves.
Encourage students to hypothesize why some waves do not show up
at certain locations. This answer is found in the layers of the
earth's interior, as students will find out if they complete Disappearing
Waves. Something inside the earth is interfering with the waves
that are trying to reach all part of the globe. (If students locate
the cities on a map, they may speculate that the oceans cause
the wave loss, since liquids always stop S waves. However, P and
S waves travel easily through the rock underneath the oceans,
and so the oceans are not the cause of the wave loss.)
an Epicenter: Students study three seismograms from
three different seismic stations (Tokyo, Sydney, and Hawaii) to
determine how far away from the epicenter each one is located.
Then students plot these three cities on a map of the Pacific
Ocean region, draw a circle around each city representing how
far away the epicenter must be, and identify the point on the
map where all three circles roughly intersect -- the epicenter.
Students may need a lot of guidance on the questions of this activity,
but the process of discovering the location of the epicenter can
be interesting. The first part of the activity is simply
determining the distance from Tokyo, Sydney, and Hawaii to the
actual epicenter of the unknown earthquake. (This is the same
earthquake that created the seismograms in Can You Read a Quake?,
so this activity refers back to the same seismograms.) In
this first part, students should confirm that Tokyo is roughly
3100 km away, and then they should determine that Sydney is roughly
4900 km away and Hawaii is roughly 8600 km away.
The second part of the activity is locating the epicenter on the
map. Show students how to understand and use the kilometer (or
mile) scale on the Pacific Ocean Map. One way is simply to measure
the given map scale in centimeters and then use this measurement
as a ratio. For example, if 1000 kilometers on the map is equivalent
to 2 centimeters on the ruler, then Tokyo is...
If Map = 1000km, Ruler = 2.0 cm
If Map = 3100 km, Ruler = 6.2 cm
In this example, students would need to draw a circle of radius
6.2 cm around Tokyo. (These calculations are not explained in
the activity.) Students should repeat the same circle-drawing
process for Sydney and Hawaii, being careful that in each case
they use the seismogram specific to that city. (If Tokyo has a
P to S time delay of 4.2 minutes and thus is 3100 km away from
the epicenter, its circle on the example map is 6.2 cm in radius.
Sydney would have a larger time delay and thus a larger distance
and a larger circle.)
Once they have accurately drawn all three circles, most students
will find that the three circles do not meet exactly in one point
but rather form a small triangle. The epicenter is somewhere inside
of this triangle -- near the Philippines.
Earth: Students explore what early scientists and philosophers
thought the inside of the earth looked like.
with students the difference between a scientist and a philosopher.
Waves: Students are asked to hypothesize why some seismic
waves disappear on their way through the interior of the earth.
In the process of answering this question, they will step through
a series of clues from seismic waves to determine and draw how
the inside of the earth is layered.
This lesson has several diagrams of the interior of the earth.
Some of these diagrams are simple; others may need some helpful
interpretation by the teacher. Students will mostly be
reading and studying diagrams. The teacher could prepare
several overhead transparencies of the wave diagrams. Overlaying
these transparencies on the overhead gives students a great visual
of circular layers inside the Earth.
Earth: After analyzing the clues from seismic waves
in the previous activity, students demonstrate their understanding
of how the inside of the earth is layered. Students can
either draw a picture or think of a model that resembles the earth.
drawings of the interior need not be complicated. They should
simply show round (spherical) layering at the five specific depths
shown in the P wave reflection diagram. Students can color
in each layer, identify which layers are solid, and then explain
with their diagram why S waves have a shadow zone and why P waves
have a shadow zone. The S waves are completely stopped at 2900
km by the molten iron/nickel outer core. The P waves that try
to glance through the outer core at an angle are deflected toward
the center of the earth at this depth and so they never arrive
at the shadow zone region.
could be asked to evaluate their drawing or model for its strengths
and Safety: Students read about how and the kinds of
damage earthquakes cause. They also focus on what can be
done to reduce earthquake hazards.
Have students practice the technique of "echo reading."
The teacher reads a sentence or portion of a sentence aloud and
then students repeat or echo what the teacher has read.
Students should follow along with the teacher. After reading
a section of the material, students close the reading material
and answer questions that focus on their comprehension of the
material just read.
Earthquakes: Students are asked to consider some of
the more difficult issues regarding predicting and preventing
This activity can be assigned in several ways:
1) Individual students write their own responses to the issues
2) An individual or a group of students is assigned one of the
geologic teams and gives an oral presentation to the class.
3) The class is divided into four groups. Groups A and B debate
the Prediction Team issue, and groups C and D debate the Prevention
to Learn: This site has not yet been completed.
Computer with internet access
Circle drawing compass
the beginning of the excursion, students will complete an internet
scavenger hunt by linking to several websites. Either hand
out or have students print the scavenger hunt worksheet.
Students access the student Seismosurfing
site on the internet webpage.
follow the procedures set up in the process section of the webpage.
They begin with TASK 1 and continue in order until all activities
student achievement by reviewing their work throughout the lesson.
Utilize the background information to ensure that students are
learning and performing the excursions accurately. Frequently
ask individual students or cooperative learning groups questions
that access their understanding.
lessons Reading the Quake and Locating an Epicenter require students
to use mathematics skills. The What should be done about
tomorrows earthquakes activity asks students to write a one paragraph
Students apply their understanding of seismographs to locating
the epicenter of an earthquake. They explore how this information
is helpful in determining possible patterns to earthquake locations
by plotting the location of epicenters on a model globe.
Students discuss what else earthquakes could tell scientists.
Students apply what they have learned about earthquake damage
and safety to analyze the risks and benefits of issuing earthquake
predictions with 10% accuracy or preventing large scale earthquakes
by creating smaller ones.
lesson assessment rubric is given as a suggestion to use in evaluating
students and may be printed separately.
The Practical Geologist. Simon & Schuster Inc. New York.
[web site]. Available from http://cse.ssl.berkeley.edu/lessons/indiv/davis/hs/QuakesEng3.html.
Accessed August 2002.
Science teachers Association. Project Earth Science: Geology.
Barbara Brooks. Science Explorer: Inside Earth. Prentice
Hall. New Jersey.