Name: __________________________________________ Date: __________________ Hour: _________

Earth Science Chapter 9 Note PacketBig Ideas of the Chapter

1. Earth’s lithosphere is broken into about a dozen major pieces and many other smaller pieces.2. These “plates” move about Earth’s surface in a process called plate tectonics.3. Plate tectonics explains the existence of earthquakes, volcanoes, mountains, oceans, and many other things.

Ch. 9.1 Continental Drift - Learning Goals1. Describe the hypothesis of continental drift2. Evaluate the evidence in support of continental drift3. Identify the main objections to Wegener's hypothesis of continental drift

9.1 Engage: How do the continents fit together?1. Get a copy of a world map from your teacher. Cut out the major continents along their coastlines.2. After you cut out continents and fit them together as a single landmass.3. Compare your large landmass with those of other students. Did anyone come up with a landmass that was

different from the others?

4. From your continental reconstruction, where did the continents fit together well?

5. Where did problems occur?

6. Use your observations to develop a hypothesis on how to get a better fit of the continents.

7. How could the overlaps and large gaps be explained?

Ch. 9.1 Notes: Continental Drift

An Idea Before Its Time

- Wegener’s continental drift hypothesis stated that the continents

had once been joined to form a single _______________.

- Wegener proposed that the supercontinent,

_______________, began to break apart 200 million

years ago and form the present landmasses.

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- Evidence

- The Continental _______________

- Matching _______________

- Fossil evidence for continental drift includes several fossil organisms found on different

landmasses.

- Rock Types and Structures

- Rock evidence for continental exists in the form of several _______________ belts that end at

one coastline, only to reappear on a landmass across the ocean.

- Ancient _______________

Evidence____________________________ Evidence _______________________

Rejecting the Hypothesis

- A New Theory Emerges

- Wegener could not provide an explanation of exactly what made the continents move. News technology

lead to findings which then lead to a new theory called _______________ _______________.

Breakup of Pangaea

Look at figure 3 on page 250 and answer the following questions.

1. In the breakup of Pangaea, what continents appear to have separated first?

2. What ocean began to form when North America separated from Africa?

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3. How was India formed?

Prehistoric Land MassesOn your Pangaea map add the

following information. Shade in the areas where these organisms fossils have been found, using the key: Glossopteris is green, Cynognathus is orange, Lystrosaurus is red, and Mesosaurus is blue.

1. What characteristics do you think enable a plant or animal to survive the breakup of a continent? Try to think of at least two characteristics.

2. Scientists have found Mesosaurus fossils on the east coast of the southern tip of South America and the west coast of South Africa. Even though we know this animal could swim, does the presence of Mesosaurus fossil remains in two places support Wegener and Du Toit's theory? Give evidence to support your ideas.

4. Do you think the breakup of Pangaea during the Jurassic period led to the extinction of some dinosaurs and the evolution of other dinosaurs?

5. Scientists have evidence that Glossopteris was found in what is now India, Antarctica, Australia, and Madagascar. What does this tell you about Glossopteris? What does it tell you about the climate and environment of Gondwanaland?

6. Based on the geologic past, we can assume that Earth is always changing. What modern-day evidence supports this idea? Hint: Think about natural disasters. Where do they often occur?

Charting the Age of the Atlantic Ocean: Quick Lab pg. 2521. If the two landmasses moved from each other at a rate of 3.3 cm/yr, how long did it take these two locations to

move to their current positions?

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2. Do you think the Atlantic Ocean would have formed at a constant rate or would that rate have varied over time. Why?

9.1 Review1. Explain how continental drift and plate tectonics are different.

2. What is the weaker, hotter zone beneath the lithosphere that allows for motion of Earth’s rigid outer shell?

a. crust b. asthenosphere c. outer core d. inner core

3. Most of Earth’s earthquakes, volcanoes, and mountain building occur

a. in the center of continents

b. in the Himalayas

c. at plate boundaries

d. at volcanic island arcs

4. Continent drift is the present day explanation for the formation of mountains, earthquakes, and volcanoes.a. True B. False

Ch. 9.2 Plate Tectonics - Learning Goals1. Explain the theory of plate tectonics2. Describe lithospheric plates3. Identify the three types of plate boundaries

Ch. 9.2 Notes

Earth’s Major Roles

- According to the plate tectonics theory, the uppermost _______________, along with the overlying crust, behaves

as a strong, rigid layer. This layer is known as the lithosphere.

- A plate is one of numerous rigid sections of the _______________ that move as a unit over the material

of the _______________.

Types of Plate Boundaries

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- _______________ boundaries (also called spreading centers) are the place where two plates move apart.

- _______________ boundaries form where two plates move together.

- _______________ _______________ boundaries are margins where two plates grind past each other without

the production or destruction of the lithosphere.

Learning Visually: page 256

1. Find a major plate that includes an entire continent plus a large seafloor.

2. Name two other examples of a divergent boundary:

3. Name two other examples of a convergent boundary:

4. Name two other examples of a transform fault boundary:

Ch. 9.2 Review1. Define lithosphere:

2. Define tectonic plate:

3. Identify, draw, and describe the three types of plate boundaries

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4. An underwater mountain chain that has formed by seafloor spreading is called a

a. divergent boundary b. mid-ocean ridge c. subduction zone

5. Two plates grind past each other at a

a. transform boundary b. convergent boundary c. divergent boundary

6. Complex mountain systems such as the Himalayas are the result of

a. oceanic-oceanic convergence b. continental-continental convergence

7. Draw a oceanic-continental convergent plate boundary. Label the subduction zone and continental volcanoes.

8. At what type of boundary do plates move apart, resulting in the upwelling of material from the mantle to create new seafloor?

a. convergent b. divergent c. transform

Hands on Learning: Model the three plate boundaries. Goal: Explain how the modeling clay reacts in each situation.

- Divergent Boundary:

- Convergent Boundary:

- Transform Fault Boundary:

Ch. 9.3 Learning Goals6

1. Explain how seafloor spreading and continental rifting cause formation of new lithosphere.2. Describe the process of lithosphere destruction that takes place at subduction zones. 3. Differentiate among subduction at oceanic-continental, oceanic-oceanic, and continental-continental convergent

boundaries.4. Describe the action of plates at a transform fault boundary.

Ch. 9.3 Notes: Actions at Plate Boundaries

Divergent Boundaries- Oceanic Ridges and Seafloor Spreading

- Oceanic ridges are continuous elevated zones on the floor of all major ocean basins. The rifts at the crest

of ridges represent _____________ plate boundaries.

- _____________ _______________ are deep faulted structures found along the axes of divergent plate

boundaries. They can develop on the seafloor or on land.

- Seafloor spreading produces new oceanic _______________.

- Continental Rifts

- When spreading centers develop within a continent, the landmass may split into two or more smaller

segments, forming a _______________.

Convergent Boundaries

- A _______________ zone occurs when one oceanic plate is forced down into the mantle beneath a second plate.

- Oceanic-Continental

- _______________ oceanic slab sinks into the asthenosphere.

- Pockets of magma develop and rise.

- Continental volcanic arcs form in part by _______________ activity caused by the subduction of oceanic

lithosphere beneath a continent.

- Examples include the Andes, Cascades, and the Sierra Nevadas.

- Oceanic-Oceanic

- Two oceanic slabs _______________ and one descends beneath the other.

- This kind of boundary often forms _______________ on the ocean floor.

- Volcanic _______________ arcs form as volcanoes emerge from the sea.

- Examples include the Aleutian, Mariana, and Tonga islands.

- Continental-_______________

- When subducting plates contain continental material, two continents __________.

- This kind of boundary can produce new mountain ranges, such as the Himalayas.

Transform Fault Boundaries

- At a transform fault boundary, plates _______________ past each other without destroying the lithosphere.

- Transform faults 7

- Most join two segments of a _______ - ________ _______________.

- At the time of formation, they roughly parallel the direction of plate movement.

- They aid the _______________ of oceanic crustal material.

Learning Plate Tectonics VisuallyWatch the video: http://education.nationalgeographic.org/media/plate-tectonics/Answer the following questions as you watch:

1. Given the limited technology and data set available to Marie Tharp and Bruce Heezen in the 1950s-1970s, what could be potential limitations of the Tharp-Heezen map?

2. At which type of tectonic boundary is oceanic crust created? At which type of tectonic boundary is oceanic crust destroyed? Provide at least one example where each type of boundary is found on the Earth.

3. If an oceanic and continental plate converge, which one (if any) would subduct?

9.3 Review1. Is the following sentence true or false? Oceanic lithosphere is created at divergent boundaries.

2. Is the following sentence true or false? Divergent boundaries only occur on the ocean floor.

3. Circle the letter of the description of a subduction zone.a. where an oceanic plate is forced beneath a second plateb. where an oceanic plate grinds past a second platec. where a continental plate grinds past a second plated. where an oceanic plate moves away from a second plate

4. Newly formed land consisting of an arc-shaped island chain is called a(n) ________________________________.

5. Is the following sentence true or false? Mountains form as a result of a collision between two continental plates.

6. Circle the letter of the example of a transform fault boundary that is NOT located in an ocean basin.a. the San Andreas Fault b. the Aleutian Trench c. the Himalayan mountains

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Match the letter on the diagram with the correct place it occurs at.

A. What kind of boundary is this? B. What kind of boundary is this?

Ch. 9.4 Learning Goals1. Explain how paleomagnetism and magnetic reversals provide evidence that supports the theory of plate tectonics.2. Evaluate how earthquakes, ocean drilling, and hot spots provide evidence that supports the theory of plate

tectonics.

Ch. 9.4 Notes: Testing Plate Tectonics

Evidence for Plate Tectonics

- ______________ is the natural remanent magnetism in rock bodies; this permanent magnetization acquired by

rock can be used to determine the location of the magnetic poles at the time the rock became magnetized.

- ______________ polarity—when rocks show the same magnetism as the present magnetism field

- ______________ polarity—when rocks show the opposite magnetism as the present magnetism field

- The discovery of strips of alternating polarity, which lie as mirror images across the ocean ridges, is among the

strongest evidence of ______________ ______________.

- Earthquake Patterns

- Scientists found a close link between deep-focus earthquakes and ocean trenches.

- The absence of deep-focus earthquakes along the oceanic ridge system was shown to be consistent with

the new theory.

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- Ocean Drilling

- The data on the ages of seafloor sediment confirmed what the seafloor spreading hypothesis predicted.

- The youngest oceanic crust is at the ridge crest, and the oldest oceanic crust is at the continental margins.

- Hot Spots

- A hot spot is a concentration of ______________ in the mantle capable of producing magma, which rises

to Earth’s surface; The Pacific plate moves over a hot spot, producing the Hawaiian Islands.

- Hot spot evidence supports that the plates __________ __________ the Earth’s surface.

Ch. 9.4 Notes - Testing Plate Tectonics 1. How is Paleomagnetism Preserved in Lava Flows evidence of plate tectonics?

2. When magnetic mineral grains in a rock form, they become magnetized in the direction parallel to Earth's existing magnetic field.

a. true b. False

3. What are the strongest evidences for seafloor spreading?

4. Define reverse polarity.

5. New basalt rocks currently forming at the oceanic ridges show reverse polarity since they become magnetized according to the present magnetic field.

a. true b. False

6. The absence of deep focus earthquakes along the oceanic ridge system is inconsistent with the theory of plate tectonics.

a. true b. False

7. Deep-focus earthquakes occur away from ocean trenches within the slab of lithosphere descending into the mantle.

a. true b. False

8. The location of the oldest oceanic crust, according to ocean drilling data is

9. The location of the youngest oceanic crust, according to ocean drilling data is

10. A hot spot is a volcanic area on a plate where a plume of material rises.a. true b. False

11. How are hot spots evidence of plate tectonics?

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What are Hotspots?*Watch the video Plate Tectonics: The Hawaiian Archipelago

1. What is a hot spot?

2. What does it mean to say that a volcano is dormant?

Ch. 9.5 Learning Goals - Mechanisms of Plate Motion

1. Compare the mechanisms of slab-pull and ridge-push as contributing to plate motion.

2. Relate the unequal distribution of heat in Earth and the mechanism of mantle convection to the movement of tectonic plates.

Learn by Doing

1. Push your textbook across the table, then pull your textbook towards you.

2. These are the two principal mechanisms of plate motion. Slab-Pull and Ridge Push.

Ch. 9.5 Notes

Causes of Plate Motion

- Scientists generally agree that _______________ occurring in the mantle is the basic driving force for plate

movement.

- Convective flow is the ________ of matter resulting from changes in temperature.

Causes of Plate Motion

- Slab-Pull and Ridge-Push11

- Slab-pull is a mechanism that contributes to plate motion in which cool, dense oceanic crust sinks into the

mantle and “_______________” the trailing lithosphere along. It is thought to be the primary downward

arm of convective flow in the mantle.

- Ridge-push causes oceanic lithosphere to slide down the sides of the oceanic ridge under the pull of

_______________. It may contribute to plate motion.

Causes of Plate Motion

- Mantle Convection

- Mantle _______________ are masses of hotter-than-normal mantle material that ascend toward the

surface, where they may lead to igneous activity.

- The unequal distribution of heat within Earth causes the thermal convection in the mantle that ultimately

drives _______________ _______________.

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