Glencoe Science Chapter Resources Earthquakes and Volcanoes Includes: Reproducible Student Pages ASSESSMENT ✔ Chapter Tests ✔ Chapter Review HANDS-ON ACTIVITIES ✔ Lab Worksheets for each Student Edition Activity ✔ Laboratory Activities ✔ Foldables–Reading and Study Skills activity sheet MEETING INDIVIDUAL NEEDS ✔ Directed Reading for Content Mastery ✔ Directed Reading for Content Mastery in Spanish ✔ Reinforcement ✔ Enrichment ✔ Note-taking Worksheets TRANSPARENCY ACTIVITIES ✔ Section Focus Transparency Activities ✔ Teaching Transparency Activity ✔ Assessment Transparency Activity Teacher Support and Planning ✔ Content Outline for Teaching ✔ Spanish Resources ✔ Teacher Guide and Answers
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Glencoe Science
Chapter Resources
Earthquakes and Volcanoes
Includes:
Reproducible Student Pages
ASSESSMENT
✔ Chapter Tests
✔ Chapter Review
HANDS-ON ACTIVITIES
✔ Lab Worksheets for each Student Edition Activity
✔ Laboratory Activities
✔ Foldables–Reading and Study Skills activity sheet
MEETING INDIVIDUAL NEEDS
✔ Directed Reading for Content Mastery
✔ Directed Reading for Content Mastery in Spanish
✔ Reinforcement
✔ Enrichment
✔ Note-taking Worksheets
TRANSPARENCY ACTIVITIES
✔ Section Focus Transparency Activities
✔ Teaching Transparency Activity
✔ Assessment Transparency Activity
Teacher Support and Planning
✔ Content Outline for Teaching
✔ Spanish Resources
✔ Teacher Guide and Answers
Glencoe Science
Photo CreditsSection Focus Transparency 1: Ken M. Johns/Photo ResearchersSection Focus Transparency 2: Prof. Sigurdur Thorarinsson/Univ. of IcelandSection Focus Transparency 3: Mehau Kulyk/Science Photo Library/Photo Researchers
Lab PreviewDirections: Answer these questions before you begin the Lab.
1. Why are safety goggles especially important when doing this lab?
2. Based on what you know about the activity from question 1, what can you expect to happenthat might resemble a cinder-cone volcanic eruption? Explain.
A volcano’s structure can influence how it erupts. Some volcanoes have only onecentral vent, while others have numerous fissures that allow lava to escape.Materials in magma influence its viscosity, or how it flows. If magma is a thinfluid—not viscous—gases can escape easily. But if magma is thick—viscous—gases cannot escape as easily. This builds up pressure within a volcano.
Real-World QuestionWhat determines the explosiveness of a volcaniceruption?
Materialsplastic film canisters baking soda (NaHCO3)vinegar (CH3COOH) teaspoon50-mL graduated cylinder
Goals■ Infer how a volcano’s opening contributes to
how explosive an eruption might be.■ Hypothesize how the viscosity of magma
can influence an eruption.
Safety Precautions
WARNING: This lab should be done outdoors.Goggles must be worn at all times. The caps ofthe film canisters fly off due to the chemical reac-tion that occurs inside them. Never put anythingin your mouth while doing the experiment.
Procedure1. Watch your teacher demonstrate this lab
before attempting to do it yourself.2. Add 15 mL of vinegar to a film canister.3. Place 1 teaspoon of baking soda in the film
canister’s lid, using it as a type of plate.4. Place the lid on top of the film canister,
but do not cap it. The baking soda will fallinto the vinegar. Move a safe distanceaway. Record your observations in theData and Observations section.
5. Clean out your film canister, and repeat thelab, but this time cap the canister quicklyand tightly. Record your observations.
Research three volcanic eruptions that have occurred in the past five years. Compare eacheruption to one of the eruption styles you modeled in this lab. Communicate to yourclass what you learn.
Conclude and Apply1. Identify Which of the two labs models a more explosive eruption?
2. Explain Was the pressure greater inside the canister during the first or second lab? Why?
3. Explain What do the bubbles have to do with the explosion? How do they influence the pressure in the container?
4. Infer If the vinegar were a more viscous substance, how would the eruption be affected?
Lab PreviewDirections: Answer these questions before you begin the Lab.
1. What about this lab makes wearing goggles a good idea?
2. Predict which type of wave will show the most motion in the spring. Explain.
If you and one of your friends hold a long piece of rope between you andmove one end of the rope back and forth, you can send a wave through thelength of the rope. Hold a ruler at the edge of a table securely with one end ofit sticking out from the table’s edge. If you bend the ruler slightly and thenrelease it, what do you experience? How does what you see in the rope andwhat you feel in the ruler relate to seismic waves?
Real-World QuestionHow do seismic waves differ?
Materialscoiled spring toyyarn or stringmetric ruler
Goals■ Demonstrate the motion of primary,
secondary, and surface waves.■ Identify how parts of the spring move in
each of the waves.
Safety Precautions
Procedure1. Use the table in the Data and Observations
section to record your observations.2. Tie a small piece of yarn or string to every
tenth coil of the spring.3. Place the spring on a smooth, flat surface.
Stretch it so it is about 2 m long (1 m forshorter springs).
4. Hold your end of the spring firmly. Make awave by having your partner snap thespring from side to side quickly.
5. Record your observations and draw thewave you and your partner made in thedata table.
6. Have your lab partner hold his or her endof the spring firmly. Make a wave byquickly pushing your end of the springtoward your partner and bringing it backto its original position.
7. Record your observations of the wave andof the yarn or string and draw the wave inthe data table.
8. Have your lab partner hold his or her endof the spring firmly. Move the spring offof the table. Gently move your end of thespring side to side while at the same timemoving it in a rolling motion, first upand away and then down and towardyour partner.
9. Record your observations and draw thewave in the data table.
Compare your conclusions with those of other students in your class. For more help,refer to the Science Skill Handbook.
Conclude and Apply1. Based on your observations, determine which of the waves that you and your partner have gener-
ated demonstrates a primary, or pressure, wave. Record in your data table and explain why youchose the wave you did.
2. Do the same for the secondary, or shear wave, and for the surface wave. Explain why you chosethe wave you did.
3. Explain Based on your observations of wave motion, which of the waves that you and yourpartner generated probably would cause the most damage during an earthquake?
4. Observe What was the purpose of the yarn or string?
5. Compare and Contrast the motion of the yarn or string when primary and secondary wavestravel through the spring. Which of these waves is a compression wave? Explain your answer.
6. Compare and Contrast Which wave most closely resembled wave motion in a body of water?How was it different? Explain.
Today, scientists use seismographs to observe and record seismic waves. Before the nineteenthcentury, however, scientists used other types of instruments to study earthquakes. These instru-ments did not record seismic waves. Instead, they indicated the magnitude or direction of anearthquake in a general way. In the 1600s in Italy, for example, scientists used a device that contained water to observe seismic waves. The amount of water spilling out during an earthquakeindicated the amount of shaking. In this lab, you will make a simple earthquake-detecting deviceand determine how it is affected by seismic waves.
StrategyYou will model and observe the effects of seismic waves.You will infer how the energy released by an earthquake affects the amplitude, or height,
of seismic waves.
Materials baking panlarge ceramic or stainless steel bowlpitcher of tap waterdroppermetersticktextbookpaper towels
Procedure1. Work with a partner. Place the baking pan
on a flat surface such as a desk or counter.Set the bowl inside the pan.
2. Pour water into the bowl from the pitcher.Fill the bowl to within 1 to 2 mm of therim.
3. Using the dropper add water to the bowluntil the surface of the water arches abovethe rim (Figure 1). This is your earthquakedetector.
4. Model an earthquake by having a partnerdrop a textbook near the detector from aheight of 2 cm. Observe what happens tothe water in the bowl. Do waves appear?Does water spill over? Record your observation in the Data and Observationssection. Add more water to the bowl withthe dropper if any spills out. Then repeatthis step, switching roles with your partner.
5. Repeat step 4 several more times. Eachtime, you should increase the height atwhich you drop the book by several centimeters.
6. If any water spills outside the baking pan,be sure to wipe it up with the paper towels.
Questions and Conclusions1. How are the waves produced by the book landing on the table similar to seismic waves?
2. Could you tell that the waves produced by some of your model earthquakes had greater amplitude than others? Explain.
3. How did you increase the magnitude of your model earthquake? How did increasing the magnitude of the earthquake affect the amplitude of the waves in your detector?
4. How could you use two earthquake detectors to model how the amplitude of seismic waves isaffected by the distance the waves travel? Explain.
Strategy Check
Can you model and observe the effects of seismic waves?
Can you infer how the energy released by an earthquake affects the amplitude of seismicwaves?
Hands-On Activities
Trial Height from Which Observations ofBook Is Dropped (cm) Earthquake Detector
Some volcanic eruptions consist of violent explosions of gases and tephra, while others involvea relatively quiet flow of lava around a vent. The type of eruption that occurs depends on both thecomposition of the magma and the amount of gas trapped in it. Thick magma that is rich in silicatends to trap steam and other gases. The more gas in the magma, the greater the pressure thatbuilds up in the volcano. The tremendous pressure that builds in silica-rich magma is releasedwhen the volcano erupts explosively.
By contrast, magma that contains less silica tends to be less explosive and flow more easily.This type of magma is rich in iron and magnesium and traps smaller amounts of gas. It producesbasaltic lava that flows from a volcano in broad, flat layers. In this lab, you will model bothbasaltic lava flows and explosive eruptions.
LaboratoryActivity22
Hand
s-On
Act
iviti
es
StrategyYou will model and observe how the buildup of pressure in a volcano can lead to an
explosive eruption.You will determine how layers of basaltic lava accumulate.
Materials newspaper old paintbrushes (3)balloons (9) spongeempty coffee can markermeasuring cup meterstickplaster of paris scissorswater piece of thick cardboard (approximately 50 cm ✕ 50 cm)1 lb. plastic margarine tubs (2) textbooksred, blue, and green food coloring small tubes of toothpaste in different colors wooden paint stirrers (3) (white, green, striped)WARNING: Never put anything you use in a laboratory experiment into your mouth.
ProcedurePart A—Modeling Explosive Eruptions1. Work in a group of five or six students. Put
on your apron and goggles, and cover yourwork area with sheets of newspaper.
2. Inflate six of the balloons. Put less air in someof the balloons than in others. You’ll need twosmall balloons, two medium, and two large.Leave the remaining balloons uninflated.
3. In the coffee can, combine 1 L of plastermix with 2 L of water. Stir the mixturewith a wooden stirrer until the mixture issmooth. You should use a bit more waterthan the directions on the box suggest.Thinner plaster will be easier to work with.
4. Pour about one-third of the mixture intoeach of the plastic tubs, leaving the final thirdin the can. Add several drops of food coloringto each container, and stir.
You should end up with three colors of plas-ter: red, green, and blue. Do this step asquickly as possible since the plaster mix willbegin to harden.
5. Using paintbrushes, coat the entire surface ofeach of the inflated balloons with a thin layerof plaster. Paint the two small balloons blue,the medium balloons green, and the largeballoons red. Using any color, paint a bandaround the center of each of the empty bal-loons, leaving the ends unpainted (Figure 1).Set the balloons on sheets of newspaper todry. If you spill any plaster while you arepainting, wipe it up with a damp sponge.
6. While the plaster is drying, skip to Part Bof the procedure.
7. To model the buildup of pressure insidemagma, try to inflate the empty balloons.What do you observe? Record your observa-tion in the Data and Observations section.
8. Spread newspapers on an open area of thefloor. With the marker, draw a large X onthe center of the paper. To model anexplosive eruption, take one of the small,blue balloons and place it on the X. Popthe balloon by stepping on it. Leave thepieces of the plaster in place and pop thesecond small balloon in the same way.WARNING: Wear your safety gogglesthroughout this experiment.
9. With the meterstick, measure the distancefrom the X to the piece of plaster thatlanded the farthest from it. This distancerepresents the radius of the debris field.Record this measurement in Table 1 theData and Observations section.
10. Repeat step 8 using the medium balloons.Measure and record the distance from theX to the piece of green plaster that landedfarthest from it.
11. Repeat step 8 using the large balloons.Measure and record the distance from theX to the piece of red plaster that landedfarthest from it.
Part B—Modeling Basaltic Lava Flows1. Use the scissors to poke a hole near the
center of the piece of cardboard. Widen thehole until it is just large enough for the capof a tube of toothpaste to fit through it.
2. Make two stacks of books and place thecardboard on top of them so that the holeis suspended about 30 cm above your worksurface (Figure 2).
3. Remove the cap from one of the tubes oftoothpaste. Stick the cap end of the tubethrough the hole so that the tube is uprightand just the mouth is sticking out the top ofthe cardboard. Model a basaltic lava flow byslowly squeezing out the contents of the tube.
Figure 2
4. Measure the height and diameter of your“lava” flow and record your measurementsin Table 2 in the Data and Observationssection.
5. To model additional eruptions, repeat steps3 and 4 using the other two tubes of tooth-paste to add to your “lava” flow.
Directions: Complete the concept map using the terms in the list below.
elastic limit magma elastic rebound lava tectonic plate
Mee
ting
Indi
vidu
al N
eeds
Directed Reading for
Content Mastery
OverviewEarthquakes and Volcanoes
occurwhen rising
occur whenrocks within
Earth’s crust arestressed past their
4.
5.
erupts through avent onto Earth’s
surface as
Locations of many
1.
volcanoes earthquakes
are related to
2.
3. ___________boundaries
break andundergo
Directions: Use the following terms to fill in the blanks in the paragraph below.
magma divergent mantle hot spots tectonic energy
Volcanoes often occur at 6. _______________ and convergent plate boundaries.
They also occur at 7. _______________ where large, rising bodies of
8. _______________ can force their way through Earth’s 9. _______________
and crust.
Like volcanoes, earthquakes also occur at 10. _______________ plate
boundaries. They are caused by the 11. _______________ generated by the plates’
movement.
Name Date Class
18 Earthquakes and Volcanoes
Section 1 ■ Earthquakes
Directions: Write the term that matches each description below on the spaces provided. The vertical, boxed letters should spell the word that answers question 10.
1. type of fault that may form when rocks are compressed2. the measurement that describes how much energy an earthquake releases3. the fastest type of seismic wave4. on the Modified Mercalli scale, a measure of the amount of structural and
geologic damage an earthquake causes5. kind of force that causes a strike-slip fault to form6. type of seismic wave that causes the most damage7. type of fault that may form when rocks are pulled apart8. type of fault that may form when rocks slide past one another in opposite direc-
tions9. instrument used to record seismic waves
10. what can happen when rocks pass their elastic limit, break, and snap back in
Instrucciones: Completa el mapa de conceptos con los siguientes términos.
límite elástico magma rebote elástico lava placas tectónicas
Lectura dirigida para
Dominio del contenido
SinopsisTerremotos y volcanes
ocurre cuandoal elevarse el(la)
ocurre cuando las rocasdentro de la corteza terres-tre son presionadas más
allá de su
4.
5.
hace erupción a travésde una chimeneahacia la superficie
terrestre como
La ubicación demuchos
1.
volcanes terremotos
está relacionada con
2.
los límites entre3. ___________
y se quiebran yexperimentan
Instrucciones: Usa los siguientes términos para llenar los espacios en blanco.
magma divergentes manto focos cálidos tectónicas energía
Los volcanes ocurren con frecuencia en los límites entre placas
6. _______________ y convergentes. También ocurren en 7. _______________, en
donde grandes masas de 8. _______________ que se elevan pueden forzar su paso
a través del(la) 9. _______________ y la corteza terrestre.
Como los volcanes, los terremotos también ocurren en los límites entre las placas
10. _______________. Los terremotos son causados por el(la)
11. _______________ generada por el movimiento de las placas.
Satis
face
las n
eces
idad
es in
divi
dual
es
Nombre Fecha Clase
22 Terremotos y volcanes
Sección 1 ■ Los terremotos
Instrucciones: Llena el crucigrama con el término que describe cada clave. Las letras en las cajas oscuras verti-cales deben darte la respuesta para la pregunta 10.
Directions: Write the term that matches each description below on the spaces provided. One or two letters havebeen given as clues for each answer. Rearrange the letters given as clues to find the term that completes the sentence in question 9.
1. instrument that records seismic waves2. seismic sea wave; becomes more dangerous as it gets closer to shore and can be very destructive3. the point inside Earth where movement from an earthquake first occurs4. vibrations caused by rocks breaking and moving as a result of a sudden release of energy5. the point on the surface of Earth located directly above the earthquake focus6. type of seismic wave that travels the fastest through rock material by causing rocks to vibrate in
the same direction as the waves7. type of seismic wave that travels the slowest and causes most of the destruction8. type of seismic wave that moves through rocks by causing rocks to vibrate at right angles to the
direction of the waves9. A building able to stand up against an earthquake is considered to be
Of all the states, California faces the highestrisk of earthquakes. This is due, in part, to amajor break in Earth’s crust that runs throughthe state for approximately 1,050 km. Thisfracture, the San Andreas Fault, was responsi-ble for the killer San Francisco earthquake in1906 and countless others since.
Earthquakes in MissouriBut a series of three earthquakes between
December 16, 1811, and February 7, 1812, tookplace not in California, but in Missouri, alonga quake zone called the New Madrid Fault. Allthree measured 8.0 on the Richter scale, mak-ing them the largest American earthquakesever. The quakes were so strong that tremorswere felt as far east as Boston and Washington,D.C. Aftershocks continued for more than ayear. Besides devastating 7,800 to 13,000 km2
of land, the earthquake caused the MississippiRiver to reverse its direction temporarily andbegin to flow upstream. The earthquake alsocaused the Mississippi to permanently changeits course and create new lakes and islandswhere there hadn’t been any before.
The New Madrid Fault is 70 km wide, 300 kmlong, and is located near New Madrid, Missouri.
It runs primarily through Missouri, Arkansas,Kentucky, and Tennessee. If an earthquake hap-pened, it could affect up to 17 states surroundingthe fault zone. For a long time, geologists thoughtthat a New Madrid earthquake was likely to happen only every 1,000 years or so.
Earthquake ConferenceUnfortunately, earthquakes can and do hap-
pen anytime, anywhere. Scientists are still unableto predict them, so they’re constantly working onways to prepare for an earthquake and to mini-mize the damage to lives and property. In the fallof 2000, representatives from 26 earthquake-prone states met at the first-ever National Earth-quake Risk Management Conference. Theydiscussed, among other things, the New MadridFault and the need to make people aware thatearthquakes don’t just happen in California.
Scientists predict that a New Madrid earth-quake could result in $20 billion in damages.With increased land development and urbansprawl hitting all the communities located onthe New Madrid Fault, it’s likely the humancost would be very high as well.
1. Where could you find information on earthquake preparedness? Is this something you andyour family need to think about? Give at least two reasons.
2. When the New Madrid earthquakes of 1811–1812 hit, there were very few people or buildingsin the area. Now scientists predict that a similar earthquake would cause damage from St. Louisto Memphis, causing billions of dollars in property damage and the loss of hundreds of lives.What effect would a New Madrid earthquake have on the land itself?
3. List some preventive measures your school could take to prepare for an earthquake.
1. Why does Iceland have so many volcanic eruptions?
2. How is geothermal energy captured in Iceland?
3. This type of energy is also called hydrothermal energy. Why do you think that is so?
Iceland is a land of fire and ice. Volcanoes,hot springs, and glaciers create a landscape ofhot and cold contrasts. Every now and then, anearthquake shakes things up. The country islocated right over the spreading Mid-AtlanticRidge where the seafloor is tearing apart.
A Volcano ZoneAs the Earth’s plates move apart in a
spreading ridge, fissures form. A long fissurezone with many shield volcanoes on its sidesruns right through the southeastern andsouthwestern parts of Iceland. This zone isabout 70 kilometers long. This has createdmany problems for the people of Iceland,since the volcanic eruptions often cause a lotof damage. Some cities have been damagedbecause they were built near what were erro-neously thought to be inactive volcanoes.
Because much of Iceland is under ice, manysmall volcanic eruptions aren’t seen, but theystill melt a lot of water. The water is captured ina caldera, the center region of a volcano, whereit then spills out every three to four years.
These water spills are called jökulhaups (yoh-kewl-owps) and can cause a great deal ofdestruction.
Putting Volcanoes to UseThe people of Iceland have learned to live
with their volcanoes. Iceland is one of themost effective countries of the world in capturing the geothermal energy of Earth andusing it to make electricity. When water seepsinto the cracks of the fissures, it is superheatedby magma. The water turns to steam andescapes through the top of the fissure as ageyser. This high-temperature steam is used torotate turbine blades. In turn, the turbinesproduce electricity for use by the people. Morethan 70 percent of the homes in Iceland areheated and lighted by geothermal energy.
Iceland is a model for other countries whenit comes to geothermal power. Geothermalenergy is environmentally clean and will probably last a long time.
Hawaii is a favorite vacation spot for peopleall over the world. Many people enjoy its beaches and pleasant weather. You can visit itseight major islands: Nihau, Kauai, Oahu,Molokai, Lanai, Maui, Kahoolawe, and Hawaii.
A New IslandThere is another “island” that is fairly large,
but most people have never heard of it. It iscalled Loihi, a Hawaiian word that means“long.” However, you cannot make a reserva-tion to stay at a hotel there, because Loihi isbeneath the ocean. It is about 20 miles fromthe southeast coast of the island of Hawaii andsits on the same hot spot as Mauna Loa andKilauea, two active Hawaiian volcanoes.
Like the other Hawaiian Islands, Loihi isvolcanic. But unlike most of the other islands,it is still being formed. Currently, the island ismore than 3,000 m high. It has about 969 mto go before it reaches sea level. If it keepsgrowing at its current rate, it should becomevisible above the surface of the ocean some-time in the next 10,000 to 100,000 years.
Scientists Discover LoihiLoihi is a volcano that is a seamount, or
sea mountain. For a long time, scientists knew it existed, but believed it was extinct.
They discovered Loihi was actually relativelyyoung and active in 1970, when an expeditionof scientists went to investigate a swarm ofearthquakes that had occurred there. Swarm isa term used to describe a large amount ofearthquake activity. Undersea photographs ofLoihi showed new-looking lava formations.Actual samples of the lava had a glass-likecrust, which confirmed the lava was new. Keepin mind that “new” in scientific, or geologic,terms can mean as long as several hundredyears ago or as recently as yesterday.
Loihi EarthquakesIn the summer of 1996, the largest swarm of
earthquakes ever recorded for the islandsoccurred at Loihi. About 4,000 earthquakesshook the seamount during a two-month periodthat summer. Once again, scientists went to Loihito study the situation. Diving down to the islandin a vessel called a submersible, they collectedsamples of lava. By using radiometry to date thelava, they found that the volcano had erupted atleast once, and possibly twice, that year.
Scientists have been monitoring Loihi usingdevices such as a hydrophone, a microphonethat works underwater. The evidence the scien-tists are collecting shows that Loihi continuesto erupt and grow.
1. How did scientists recognize that Loihi was still growing?
2. Why do you think Loihi is sometimes called a submarine island?
3. If Loihi reaches sea level in 10,0000 years, what would its average rate of growth per year be?What would its average rate of growth per year be if it reaches sea level in 100,000 years?
4. Do you think other new islands are possible in the Hawaiian chain? Explain.
1. Modified Mercalli intensity scale—measures an earthquake’s intensity based on the amount
of __________________________________
2. Most earthquake damage is caused by ___________ waves.
3. Tsunamis—when an earthquake occurs on the _______________, the sudden movementpushes against the water and creates powerful waves that can travel thousands of kilometers.
E. Seismic-safe structures are able to stand up against an earthquake’s _______________.
1. Many high-rise buildings stand on huge steel and rubber _______________.
2. Underground water and gas pipes are replaced with pipes that will _______________.
3. Highways have cement pillars with spiral _______________ around them.
F. Predicting Earthquakes
1. Long-range forecasts predict whether an earthquake is likely to occur in a given area within
_____________ years.
Section 2 Volcanoes
A. Volcanoes—cone-shaped hills or mountains formed by ___________________
1. When magma flows onto Earth’s surface through a vent, it is called ________.
2. __________—bits of rock or solidified lava dropped from the air after an explosive eruption.
3. Some volcanoes form where Earth’s plates ___________.
a. One plate ____________, or is forced underneath, the other.
b. Part of the plate that is forced underneath _________, forming magma chambers.
4. Avalanches of hot, glowing molten rock that flow on cushions of hot gases down a side of a
volcano are called _____________________.
5. How forceful an eruption is depends on the composition of the _________.
a. More silica makes magma _____________________.
b. More iron and magnesium make magma _____________________.
c. Water vapor trapped in the magma becomes steam and _____________________.
6. The type of _______________ and _______________ contained in the lava determine the
The Richter scale was first used to rate the strength of earthquakesin 1935. Since then, we’ve learned a great deal about the causes ofearthquakes, but predicting when an earthquake will strike remainstricky.
Nobody’s Fault at All
1. What happens during an earthquake?
2. What parts of an earthquake can be measured?
3. Why is it easier to predict where an earthquake will strike thanwhen it will strike?
In November of 1963, the Atlantic Ocean got a new island. Theisland was named Surtsey after Sutur, a mythological fire god. Thenew island was the result of a volcanic eruption very near Iceland.
Does the stork bringbaby islands?
1. Looking at the photo, how did the island of Surtsey form?
2. What do volcanoes and earthquakes have in common?
3. What unique learning opportunities might scientists have onSurtsey?
The dots on this image show places where earthquakes haveoccurred. The line of dots in the middle of the Atlantic Ocean is the Mid-Atlantic Ridge. As you can see, the area is geologically veryactive!
Earth Shattering
1. What do you notice about the locations of the earthquakes shownabove?
2. What other geological activity is likely to follow a similar pattern?
3. Give an example of some geological activity that does not occuralong these boundaries.
1. What instrument records seismic waves from all over the world?
2. What is the name of the scale that gives the magnitude of energy an earthquake releases?
3. What two waves are indicated on the transparency? What do the abbreviations stand for?
4. What is the point on Earth’s surface directly above an earthquake’s focus?
5. What do seismologists study?
6. What do the height of the lines on a seismograph measure?
7. Look at the graph to determine the approximate distance to the epicenter if the first P-wavearrives at the recording station two minutes ahead of the first S-wave.