Plate Boundaries and California; Grade 6 Chapter 5 5 Plate Boundaries and California ... † The Glencoe Science Web site at science.glencoe.com ... Read and complete a lab safety

Chapter 5Plate Boundaries

and California

LEVELED ASSESSMENT Chapter Review

Chapter Tests

Test A (Below Level) BL

Test B (On Level) OL

Test C (Advanced Learner) AL

LABS For leveled labs, use the

CD-ROM.

Lab worksheets from Student Edition Labs

MiniLab

Lab: Version A (Below Level) BL

Lab: Version B (On Level) OL

(Advanced Learner) AL

UNIVERSAL ACCESS/LEVELED RESOURCES Target Your Reading

Chapter Content Mastery English (Below Level) BL

Chapter Content Mastery Spanish (Below Level) BL

Reinforcement (On Level) OL

Enrichment (Advanced Learner) AL

READING SUPPORT Content Vocabulary

Chapter Outline

TEACHER SUPPORT AND PLANNING Chapter Outline for Teaching

Teacher Guide and Answers

Includes:

CHAPTER RESOURCES

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Printed in the United States of America.

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Table of Contents

Additional Assessment Resources available with Glencoe Science:

• ExamView® Assessment Suite• Assessment Transparencies• Performance Assessment in the Science Classroom• Standardized Test Practice Booklet• MindJogger Videoquizzes• Vocabulary PuzzleMaker at science.glencoe.com• Interactive Classroom• The Glencoe Science Web site at science.glencoe.com• An interactive version of this textbook along with assessment resources are

available online at mhln.com.

To the Teacher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iv

Reproducible Student PagesHands-On ActivitiesMiniLab: How can you model movement of a fault? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Lab Version A: Earthquake Depths and Plate Boundaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Lab Version B: Earthquake Depths and Plate Boundaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Meeting Individual NeedsBelow, On, Advanced

Target Your Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Chapter Content Mastery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Spanish Chapter Content Mastery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Content Vocabulary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Chapter Outline Worksheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

AssessmentChapter Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Chapter Test A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Chapter Test B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Chapter Test C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Teacher Support and PlanningChapter Outline for Teaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T2Teacher Guide and Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T6

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Student Lab/Activity Safety Form

Student Name: ________________________________

Date: ________________________________

Lab/Activity Title: ________________________________

In order to show your teacher that you understand the safety concerns of this lab/activity, the following questions must be answered after the teacher explains the information to you. You must have your teacher initial this form before you can proceed with the activity/lab.

1. How would you describe what you will be doing during this lab/activity?

2. What are the safety concerns associated with this lab/activity (as explained by your teacher)?

•

•

•

•

•

3. What additional safety concerns or questions do you have?

Teacher Approval Initials

Date of Approval

Adapted from Gerlovich, et al. (2004). The Total Science Safety System CD, JaKel, Inc. Used with Permission.

Plate Boundaries and California 1

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A fault is formed when rocks are deformed to the point of breaking, and movement occurs along the break. Scientists observe the movement of faults in nature. This allows them to determine the types of stresses that caused the faulting.

Procedure 1. Read and complete a lab safety form. 2. Cut a shoebox lid in half along its width. The

bottom of the box will represent the surface of the earth.

3. Turn the shoebox over. The bottom of the box will represent the surface of the Earth.

4. Use scissors to cut the shoebox in half along its width. Cut at an angle to model an inclined fault surface. Examine Figures 4, 5, and 6 in your textbook for examples of how faults look in three dimensions.

5. Tape the two halves of the shoebox lid over the shoebox halves to make the fault slope.

6. Model fault movement for a normal, a reverse, and a strike-slip fault.

7. Challenge option: Use poster paints to paint rock layers on a side of the shoebox lid before it is cut to see how the layers move relative to each other.

Analysis1. Illustrate fault movement for each scenario in the space below. Use arrows to show how the

shoebox halves move relative to each other.

2. Relate a type of stress to each of the fault types that you modeled above. Use arrows to indicate the directions of stress on your illustrations.

MiniLabCHAPTER 5How can you model

movement of a fault?

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4 Plate Boundaries and California

Problem Not all earthquakes occur at the same depth in the lithosphere. Use your knowledge of types of plate boundaries to determine a general relationship between plate boundary and the depths of earthquakes experienced there.

Form a Hypothesis • Describe the types of stress that cause earthquakes. • Review the basic structure of divergent boundaries, transform boundaries,

and convergent boundaries.

Hint: Refer back to Figures 10 and 11 and Table 1 in your textbook. • Earthquakes range in depth from zero, at Earth’s surface, to about

700 kilometers deep. The shallow range is from 0 km to about 70 km deep, intermediate earthquakes are about 70 km to 300 km deep, and deep earthquakes occur from about 300 to 700 km below the surface.

• Make a statement about which boundaries you think will have shallow, intermediate, or deep earthquakes associated with them.

Materialsworld map with latitude and longitude linesplate boundary mapgraph papercomputer with Internet access

Collect Data and Make Observations

Directions: Check the boxes below as you complete each step of the procedure.

■■ 1. Visit ca6.msscience.com to research data on recent earthquakes.

■■ 2. Study the data table on the next page or make one like it on a separate sheet of paper.

■■ 3. Record the following: latitude (degrees North or South), longitude (degrees East or West), depth (km), and a location (e.g., near Beijing, China) for each earthquake. Leave the plate boundary column blank for now.

Earthquake Depths and Plate Boundaries

CHAPTER 5

VERSION ALab

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Earthquake Locations and Depths

Latitude Longitude Depth (km) Location Plate Boundary Type

Analyze and Conclude1. Compare the earthquake locations you plotted with a plate boundary map of the world.

2. Specify, in the table above, the type of plate boundary associated with each earthquake or whether an earthquake was not associated with any plate boundary.

Lab: Version A CONTINUED

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Lab: Version A CONTINUED

CommunicateCompare and Contrast Write a paragraph that compares and contrasts the depth of earthquakes that you would expect to occur at transform and ocean-to-continent convergent plate boundaries. Explain any differences in depth ranges for these types of plate boundaries.

3. Determine which plate boundaries experience the deepest earthquakes.

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Problem Not all earthquakes occur at the same depth in the lithosphere. Use your knowledge of types of plate boundaries to determine a general relationship between plate boundary and the depths of earthquakes experienced there.

Form a Hypothesis • Describe the types of stress that cause earthquakes. • Review the basic structure of divergent boundaries, transform boundaries,

and convergent boundaries.

Hint: Refer back to Figures 10 and 11 and Table 1 in your textbook. • Earthquakes range in depth from zero, at Earth’s surface, to about 700

kilometers deep. The showllow range is from 0 km to about 70 km deep, intermediate earthquakes are about 70 km to 300 km deep, and deep earthquakes occur from about 300 to 700 km below the surface.

• Make a statement about which boundaries you think will have shallow, intermediate, or deep earthquakes associated with them.

Materialsworld map with latitude and longitude linesplate boundary mapgraph papercomputer with Internet access

Collect Data and Make Observations

Directions: Check the boxes below as you complete each step of the procedure.

Earthquake Depths and Plate Boundaries

CHAPTER 5

VERSION BLab

■■ 1. Visit ca6.msscience.com to research data on recent earthquakes.

■■ 2. Study the data table on the next page or make one like it on a separate sheet of paper.

■■ 3. Record latitude, longitude, depth (km), and a location for each earthquake. Leave the plate boundary column blank for now.

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Name __________________________________________________ Date _____________________ Class ____________


Earthquake Locations and Depths

Latitude Longitude Depth (km) Location Plate Boundary Type

Analyze and Conclude 1. Compare the earthquake locations you plotted with a plate boundary map of the world.

2. Specify, in the table above, the type of plate boundary associated with each earthquake or whether an earthquake was not associated with any plate boundary.

3. Determine which plate boundaries experience the deepest earthquakes.

Lab: Version B CONTINUED

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Going Further

Challenge 4. Use a copy of a world map. Locate each earthquake on the map.

5. Calculate the percentage of earthquakes occurring along a plate boundary versus the number of earthquakes occurring in the middle of a plate. Was the percentage what you would have predicted? Explain why or why not.

6. Construct a graph showing the magnitude of each earthquake. Use a separate sheet of paper.

7. Analyze What do you notice about the magnitude of the earthquakes during this period? Were most of the earthquakes of low or high magnitude?

ExtendIn this lab, you observed patterns in the location of earthquakes. Geologists study patterns related to the location, frequency and magnitude of earthquakes to help them predict future earthquakes. Research earthquake patterns in your area over the last fifty years. Write a report sharing your findings.

Lab: Version B CONTINUED

CommunicateCompare and Contrast Write a paragraph that compares and contrasts the depth of earthquakes that you would expect to occur at transform and ocean-to-continent convergent plate boundaries. Explain any differences in depth ranges for these types of plate boundaries.


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Name __________________________________________________ Date _____________________ Class ____________

Target Your Reading

Name __________________________________________________ Date _____________________ Class ____________

Use this to focus on the main ideas as you read the chapter. 1. Before you read the chapter, respond to the statements below on your worksheet or on a

numbered sheet of paper. • Write an A if you agree with the statement. • Write a D if you disagree with the statement.

2. After you read the chapter, look back to this page to see if you’ve changed your mind about any of the statements. • If any of your answers changed, explain why. • Change any false statements into true statements. • Use your revised statements as a study guide.

BeforeYou Read

A or DStatement

AfterYou Read

A or D

1. Part of California will eventually break off and fall into the Pacific Ocean.

2. The San Andreas Fault is part of a plate boundary.

3. Plate boundaries extend deep into Earth’s lithosphere.

4. Subduction occurs when oceanic and continental lithospheric plates more toward each other.

5. Mountains in western South America result from a continent-to-continent convergent plate boundary.

6. Faults are surfaces where rocks break and move.

7. Los Angeles and San Francisco are moving closer to one another because of a transform plate boundary.

8. When rocks are subjected to compression stress, they become thinner.

9. The Cascade Range forms on a divergent plate boundary.

Plate Boundaries and CaliforniaCHAPTER 5

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Chapter Content Mastery

Directions: Circle the term or phrase in parentheses that correctly completes the sentence.

1. Stretching and thinning is the deformation that results from (compression/tension stress).

2. If rocks are squeezed, compression makes the rocks (thicker/thinner).

3. When rock is pushed in opposite directions, (tension/shear) stress results.

4. In places where rocks are pushed together, compression produces (strike-slip/reverse) faults.

5. When plates slide past each other, (shearing/stretching) produces strike-slip faults.

6. When two plates of lithosphere are moving (together/apart), it is called a divergent plate

boundary. Most divergent plate boundaries are located on the (seafloor/tops of mountains).

Directions: Complete the concept map using the terms listed below.

deep-sea trenches major earthquakes mid-ocean ridges

rift valleys volcanic islands volcanic mountains

Interactions at Plate BoundariesCHAPTER 5

LESSON 1

Plate boundaries

transformboundaries

11.

10.9.8.

12. 13.

divergentboundaries

convergentboundaries

include includeinclude

formform

cause

and and

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Chapter Content Mastery

Directions: Complete the following sentences using the words listed below.

approaching boundaries convergent earthquake

North American plate rocks strike-slip

1. Because the San Andreas Fault is a transform boundary, it is a system of faults.

2. The Pacific Plate moves northwest, relative to the , at about 3.4 cm/y. It does not slide smoothly and each time a jerky movement occurs, a(n)

happens.

3. The Gorda and Juan de Fuca plates are two small lithospheric plates that are forced beneath the

California coast, forming a plate boundary.

4. California has many mountains because mountains form at plate .

5. Los Angeles and San Francisco are each other about as fast as your fingernail grows.

6. The of the Klamath Mountains, coastal ranges, peninsular ranges, and the Sierra Nevada formed when an ancient oceanic plate subducted beneath the North American Plate.

Directions: Circle the letter of the correct answer.

7. On which plate is most of California located? A. Pacific B. Juan de Fuca C. North American

8. On which plate is Los Angeles located? A. Pacific B. Juan de Fuca C. North American

9. At what velocity does the Pacific Plate move northwest, relative to the North American Plate? A. 3.4 m per year B. 3.4 cm per year C. 340 m per year

California GeologyCHAPTER 5

LESSON 2

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Las fronteras de las placas y California 13

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Nombre _______________________________________________ Fecha _____________________ Clase ____________

Dominio del contenido

13.12.

8. 9. 10.

11.

Las fronterasconvergentes

Las fronteras divergente

Las fronterastransformantes

Las fronteras de las placas

Instrucciones: Circula el término o frase entre paréntesis que correctamente complete la oración.

1. La extensión y la disminución es la deformación que resulta de la

(comprensión/estrés de tensión).

2. Si se aprietan las rocas, la compresión hace las rocas más (gruesas/delgadas).

3. Cuando se empuja la roca en direcciones opuestas, el estrés que resulta es de (tensión/corto).

4. En lugares donde las rocas se empujan juntas, la compresión produce faltas de

(golpe-deslizamiento/reverso).

5. Cuando las placas se deslizan de un lado al lado de la otra, el (la) (corto/extensión) produce

fallas de deslizamiento.

6. Cuando dos placas de la litosfera se están (moviendo juntas/separando), se le llama una placa de

frontera divergente. La mayoría de las fronteras divergentes están en

(el piso del mar/las cimas de las montañas).

Instrucciones: Completa el mapa de conceptos usando los siguientes términos.

cadenas del mediado del océano islas volcánicas montañas volcánicas

terremotos fuertes valles de desunión zanjas submarinas

Las interacciones en las fronteras de las placas

CAPÍTULO 5

LECCIÓN 1

incluyen incluyenincluyen

formanforman

forman

y y

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14 Las fronteras de las placas y California

Nombre _______________________________________________ Fecha _____________________ Clase ____________

Dominio del contenido

Instrucciones: Completa las oraciones usando las siguientes palabras.

acercando convergente fronteras golpe-deslizamiento

norteamericana rocas terremoto

1. La Falla de San Andrés es una frontera de transformación porque es un sistema de fallas

de .

2. La placa Pacífica se mueve al noroeste, relativa al (a la) , a aproximadamente 3.4 cm por año. No se desliza suavemente y cada vez que ocurre un

movimiento espasmódico, ocurre un(a) .

3. Las placas Gorda y Juan de Fuca son dos placas pequeñas litosferas que están forzadas bajo la

costa de California, formando una frontera de placas .

4. California tiene muchas montañas porque las montañas forman en los (las) de placas.

5. Los Angeles y San Francisco se están aproximadamente tan rápido como crecen tus uñas.

6. Los (Las) de las montañas Klamath, las cadenas costales, las cadenas peninsulares y la Sierra Nevada se formaron cuando una placa oceánica antigua se deslizó debajo de la placa norteamericana.

Instrucciones: Circula la letra de la respuesta correcta.

7. ¿California está localizada en qué placa? A. Pacífica B. Juan de Fuca C. norteamericana

8. ¿Los Ángeles está localizado en qué placa? A. Pacífica B. Juan de Fuca C. norteamericana

9. La placa Pacífica se mueve al noroeste, relativa a la placa norteamericana, ¿a qué velocidad? A. 3.4 m por año B. 3.4 cm por año C. 340 m por año

La geología de CaliforniaCAPÍTULO 5

LECCIÓN 2

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Reinforcement


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Interactions at Plate Boundaries

Directions: Write the letter of the word that best matches each description in the blank.

A. tension stress B. compression C. strike-slip D. normal faults

1. rocks slide past each other sideways in this type of fault

2. this type of stress makes rocks thicker

3. these are produced when tension stresses inside Earth pull rocks apart

4. the results from this stretching and thinning of Earth’s plates

Directions: Four diagrams are shown in the table below. Label and describe each diagram in the space provided to complete the table.

Diagram Type of Boundary and Motion at Boundary Diagram Type of Boundary and

Motion at Boundary

5. 6.

7. 8.

CHAPTER 5

LESSON 1

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Reinforcement


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California Geology

Directions: For each statement below, write either divergent, convergent, or transform in the space provided to indicate the type of plate boundary at each location.

1. where mid-ocean ridges are located

2. the San Andreas Fault is located on this type of boundary

3. where volcanic eruptions occur

4. where rift valleys form

5. where the Cascade Range is located

Directions: Respond to each statement on the lines provided.

6. Identify the two plates that meet at the San Andreas Fault, and indicate in which direction each plate is moving.

7. Describe how the Cascade Mountains were formed.

8. Name a type of landform that can be created at all three types of plate boundaries in California.

CHAPTER 5

LESSON 2

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Enrichment Predicting Earthquakes

Although earthquakes often seem to strike without warning, the energy it takes to cause an earthquake takes years to build up in the form of stresses in Earth’s crust. These stresses occur at plate boundaries and reach critically high levels that can cause an earthquake. Current assessments of earthquake risk are based on data regarding the history of earthquakes in an area (seismic history), studies of the geology of an area, and computer models. Despite our advances in technology, scientists can’t predict with accuracy when earthquakes will occur.

Using Satellites to Monitor Ground Movement

This might be changing however. There are now several satellite-based methods that show promise in terms of helping to predict earthquakes well before they strike. One method is called Interferometric-Synthetic Aperture Radar (InSAR). InSAR uses two radar images of a tectonic area and combines them in a process called data fusion, so that any changes in ground motion (comparing one image to the other) at the surface can be detected. This technique allows scientists to see motions of land as tiny as 1 mm per year along fault lines!

By monitoring these motions using landscape-level views provided by satellites, they can determine where along fault lines areas of high stress are building up—areas where earthquakes are most likely to occur.

Eventually, scientists using InSAR data hope to be able to issue “hazard assessments” for a given fault. For example, they might report that the likelihood of a major earthquake occurring along the San Andreas fault during the coming month is 10%.

Other Promising New TechnologiesWhile InSAR helps to improve the data

available to detect the movement of Earth along fault lines, other earthquake prediction methods are being researched. One of these methods looks for surges in infrared (IR) radiation that are associated with earthquakes. Satellites equipped with IR cameras could be used to detect these hotter spots from space. While no one knows for certain what causes rocks under pressure to emit infrared radiation, this technique might be promising.

Scientists have also recorded tiny, slow changes in Earth’s magnetic field just before major earthquakes. Though theories exist, the cause of these changes is also unknown. They are hoping that these magnetic changes might be successfully detected by a satellite that could monitor most of Earth’s surface for earthquakes.

CHAPTER 5

LESSON 1

Directions: Answer the questions below.

1. Assess How has satellite technology improved our earthquake predition capabilities?

2. Use resources at your local library to research and write a newspaper article reporting the facts about a past California earthquake as if you were there. What was the magnitude of the quake and what do you think caused it? Use a separate sheet of paper to write your article.

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EnrichmentAxial Volcano—Evidence for Seafloor Spreading

What happens when a volcano erupts underwater? Ocean scientists had the opportunity to find out in January of 1988 when Axial erupted. Axial is an underwater volcano, or seamount, located about 480 km west of Oregon’s coast. It is the largest of all the underwater structures on the Juan de Fuca Ridge.

Quakes Along the SeafloorUnderwater listening instruments called

hydrophones, which are used by the Navy to hear submarines, first picked up rumblings from Axial on January 25. Scientists recorded nearly 7,000 earthquakes during the first four days alone. Scientists hypothesized that these quakes resulted from hot magma moving and cracking rocks, uncapping the top of Axial. They followed a line in the seafloor where the Juan de Fuca oceanic plate is moving eastward, away from the Pacific oceanic plate. East of the shoreline, the Juan de Fuca plate is being pushed under the North American continental plate.

Creating New SeafloorThe scientists discovered that when Axial

erupted, boiling-hot water shot up out of the volcano, followed by a great quantity of hot lava. Much of this lava filled part of the gap between the Pacific plate and the Juan de Fuca plate, creating new seafloor. Having lost so much magma, Axial caved in somewhat—by about 3.2 m in the center.

MegaplumesAround the same time, another group of

scientists was on a 52 m research ship, the Wecoma, on the ocean’s surface about 1.5 km above the volcano. They fought stormy conditions to gather data such as water temperature, water current flow, and samples of chemicals from the eruption. In 1986, scientists had learned that underwater volcanoes can cause underwater “hurricanes,” called megaplumes, which shoot hot water loaded with minerals and lifeforms about 305 m up from the bottom. Only seven megaplumes in the world had been observed previously.

Hydrothermal VentsAt Axial’s summit sits a rectangular caldera

(roughly 20 km2 in area) between two rift zones. In the dark caldera, hydrothermal vents furnish heat and “food” such as hydrogen sulfide—poisonous to most creatures—to communities of bacteria and tube worms comfortable in temperatures hotter than the boiling point of water.

Axial provides scientists with a model for the rest of Earth’s approximately 64,000 km or so of mid-ocean ridges. Various groups of scientists are conducting long-term studies of Axial and other areas along the Juan de Fuca Ridge, focusing on various aspects of seafloor exploration.

CHAPTER 5

LESSON 2

Directions: Respond to the statements below.

1. Evaluate and describe how seafloor spreading occurs along the Juan de Fuca Ridge.

2. Assess Do you think that the rocks near Axial are younger or older than the rocks in Oregon? Explain. Use a separate sheet of paper for your answers.

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Content Vocabulary

Directions: Match each term with its definition by writing the correct letter on the blank.

CHAPTER 5

Plate Boundaries and California

1. a break or crack in rock

2. when the rocks on one side of a fracture surface move relative to the rocks on the other side

3. the block of rock that lies below the fault

4. the process that pulls a continent apart

5. process in which one plate is forced down into the mantle beneath another plate

6. this fault is an example of a strike-slip fault that extends the length of much of California

7. long, narrow area formed when the hanging wall of a fault slips down

8. the block of rock that lies above the fault

A. continental rifting

B. fault

C. footwall

D. fracture

E. hanging wall

F. rift valley

G. San Andreas

H. subduction

Directions: Complete each statement with the correct phrase below.

moving apart moving together moving past each other

9. A convergent plate boundary is where two plates are .

10. A divergent plate boundary is where two plates are .

11. A transform plate boundary is where two plates are .

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Content Vocabulary CONTINUED

Directions: Write the correct term on the line beside its definition.

compression convergent divergent mid-ocean ridges

normal reverse shear strike-slip

tension transform

12. stress that causes rocks to squeeze together and become thicker

13. stress that causes rocks to pull apart and become thinner

14. looks similar to a normal fault, but the blocks of rock move differently

15. stress that causes rocks to push against each other in opposite directions

16. fault, such as Death Valley, that slopes at an angle

17. vertical fault produced when shear stress causes rocks to slide past each other sideways

18. two plates of lithosphere that are moving apart

19. two plates of lithosphere that are moving toward each other

20. a boundary where two plates move sideways past one another

21. where most divergent plate boundaries occur along the seafloor

Directions: Complete each statement with the correct phrase below.

22. Most of California is on the continental Plate.

23. A small part of California, west of the lies on the oceanic Pacific Plate.

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Chapter Review

Part A. Vocabulary Review

Directions: Complete each sentence using the terms listed below.

compression convergent divergent

fault fracture Pacific Plate

rift valley San Andreas Fault shear

subduction tension transform

1. Most plate boundaries occur on the seafloor at mid-ocean ridges.

2. At a plate boundary, lithosphere is neither formed nor recycled.

3. Plates collide at plate boundaries.

4. When the rocks on one side of a fracture surface move relative to the rocks on the other side,

the fracture is a .

5. A forms as the hanging wall of a normal fault slips down.

6. is a process in which one plate is forced down into the mantle beneath another plate.

7. The system of faults that runs from Cape Mendocino to the Salton Sea is called

the .

8. A break, or crack, in a rock is called a .

9. stress causes rocks to pull apart and become thinner.

10. A lithospheric plate becomes thicker due to stress.

11. Lithospheric plates move sideways and do not change thickness with stress.

12. A small part of California, including Los Angeles, is located on

the .

CHAPTER 5


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Chapter Review CONTINUED

Part B. Concept Review

Directions: Fill in the type of plate boundary associated with each landform in the table below.

Landform Plate Boundary Type

1. Los Angeles Basin

2. Cascade Range

3. San Andreas Fault

4. Mid-Atlantic Ridge

Directions: Determine the type of fault that matches each phrase below.

5. rocks being pushed together

6. rocks being pulled apart

7. rocks slide past each other sideways

Directions: Explain what happens as a result of the following types of plate collisions. Use complete sentences.

8. continent-to-continent

9. ocean-to-ocean

10. ocean-to-continent

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Chapter Outline

Lesson 1: Interactions at Plate Boundaries

A. Stress and deformation result when lithospheric plates at plate boundaries.

1. Rocks that are subjected to and become deformed.

a. When rocks permanently change shape by folding, it is called deformation.

b. When rocks snap back to their original shapes after stress is removed, it is called

deformation.

c. A break or crack in rock is called a .

d. A results if the rock on one side of the fracture surface moves relative to the rock on the other side.

2. stress results when plate rock is pulled apart and it

becomes .

3. If plate rock is squeezed, the stress of makes the

rocks .

4. When plate rock is pushed in opposite directions, the force of

stress acts on it but does not change the of the plate.

B. Different types of stress produce different types of .

1. Geologists measure the of the fault surface to figure out which way the broken sections of rock have moved.

a. The hanging wall is the block of rock that lies the fault.

b. The block of rock that lies below the fault is called the .

2. Tension forces inside Earth pull rock apart, producing faults.

a. This kind of fault at an angle.

b. When rock breaks and along the fault, the

wall slides down the footwall.

CHAPTER 5


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Chapter Outline CONTINUED

3. In places where rocks are pushed together, compression produces faults.

4. Where plates slide past each other, shearing stresses produces faults.

a. Strike-slip faults often are , not inclined.

b. The rocks each other sideways.

C. The boundary formed where two plates of lithosphere are moving apart is

a .

1. occur along divergent plate boundaries.

a. New seafloor forms as two plates of lithosphere move .

b. Seafloor located farther from a divergent plate boundary is because it cools and becomes denser as it moves away from the center of the ridge.

2. is the process that pulls a continent apart.

a. A long, narrow forms when a slips down.

b. collects on the floor of the rift valley, pushing the valley deeper.

3. The East African Rift and the Gulf of California are examples of modern continental

rift .

D. A plate boundary is formed when two lithospheric plates move toward each other.

1. Where two oceanic plates move toward each other, one of the

plates the other plate and is forced down into the mantle in a

process called .

a. The colder, older, slab is usually forced down into the mantle,

forming a on the seafloor where it bends.

b. High temperature and in the mantle release

from minerals in the slab.

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c. Water rises from the mantle and causes rock to , and

rises to the surface, forming volcanoes.

2. Sometimes an oceanic plate and a plate collide at a convergent boundary.

a. The plate always subducts because continental rocks are less

than oceanic rocks.

b. The melting of subducted rock produces a curved string of along the leading edge of the continent.

3. When two continental plates collide, stress forces crust to

and form .

E. A exists where two plates grind past

one another, eventually causing .

1. Lithosphere is neither formed nor recycled at these boundaries.

2. Oceanic transform plate boundaries connect pieces or segments of

the .

3. Continental transform plate boundaries slice through lithosphere.

a. Large resulting from movement along these faults can be very

if they occur in populated areas.

b. The in California is the best studied continental

transform in the world.

c. Most of California is on the continental . But a small part of California, west of the San Andreas fault lies on the adjacent

plate.

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Lesson 2: California Geology

A. Transform Plate Boundary

1. Most of California is situated on continental lithosphere of the .

2. A small part of California, west of the San Andreas Fault, lies on the adjacent

oceanic .

3. The San Andreas Fault is a transform plate boundary. It is also a zone

of .

4. The Pacific Plate moves northwest relative to the , at a velocity of about 3.4 cm per year.

a. It does not move smoothly, but instead moves in . These jerky

movements cause .

B. Convergent Plate Boundary

1. Just offshore of Northern California, there are small oceanic lithospheric plates.

a. These plates, known as the and , are subducted beneath the coast. This subduction forms a convergent plate boundary.

b. Melting above this subduction zone produces the volcanic of the Cascade Range.

C. California’s Mountains formed from interactions at several boundaries.

1. at California’s convergent plate boundaries has been important in forming the state’s mountains.

2. Granitic rocks form under volcanic mountains where plates .

a. During mountain building, compressive stresses and heat produce

rocks.

b. The Klamath Mountains, coastal ranges, peninsular ranges and all contain igneous and metamorphic rocks that formed far below the surface when an

ancient oceanic plate beneath the North American plate.

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3. Above the subduction zone in northern California, granitic rocks are forming deep in the

crust and activity produces the on the surface.

a. Both Lassen Peak and are active volcanoes in this mountain range.

4. There are some mountains in California that have formed because of stresses.

a. The west of Death Valley is rising up as the crust in Eastern California stretches.

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Plate Boundaries and California; Grade 6 Chapter 5 5 Plate Boundaries and California ... † The Glencoe Science Web site at science.glencoe.com ... Read and complete a lab safety

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