Unit: 4 Plate Tectonics LT 4.1 Earth s Interior: I can draw and interpret models of the interior of the earth.

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1 Unit: 4 Plate Tectonics LT 4.1 Earth s Interior: I can draw and interpret models of the interior of the earth. 1. Can you draw the 3-layer model and the 5-layer model of the Earth? #1 Yes I can: 2. Can you explain why we have two different models? (hint: think properties) LT 4.2 Plate tectonics: I can explain the evolution of tectonic theory, the evidence used to develop the theory, and a possible mechanism for plate motion. 1. Can explain the difference between continental drift and plate tectonics? Yes I can: 2. Can you list and explain the evidence for plate tectonics? 3. Can you explain what causes the plates to move? 4. Can you describe the process of convection? LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. 1. Can you explain the difference between continental tectonic plates and oceanic plates? Yes I can: 2. Can you name the 5 plate interactions? (i.e. c-c convergent) 3. Can you explain what is made at each plate interaction? (i.e. volcano, subduction, mid-ocean ridge )

2 Vocabulary I should know: #2 1. Crust Outer most layer of the Earth in the compositional model. It is composed of silicate material making it less dense than the other layers 2. Mantle Middle layer of the Earth in the compositional model. It is composed of a mixture of the silicates and iron 3. Core Inner most layer of the Earth in the compositional model. It is composed of iron and magnesium which makes it very dense. 4. Lithosphere - Outer most layer of the Earth in the structural model. It has a solid structure. 5. Asthenosphere - Second layer from the surface in the structural model. It has a plastic structure, meaning it s a solid that flows, much like playdoh. 6. Mesosphere - Middle layer of the Earth in the structural model. It has a solid structure. Meso means middle. 7. Outer core Fourth layer down in the structural model. It is made of liquid iron (Fe) and generates a magnetic field around the earth like a magnet. The magnetic field protects us from harmful radiation from outer space. 8. Inner core - Fifth and final layer of the structural model. It is made of solid iron (Fe). 9. Convergent When plates move toward each other. 10. Divergent When plates move away from each other. 11. Continental Crust that makes up land. It makes up land because it is less dense (made of felsic material) and thicker than oceanic crust. 12. Oceanic - Crust that makes up the ocean floor. It makes up the ocean because it is denser (made of mafic material) and thinner than continental crust. 13. Rift valley a valley that is formed when two continental plates move away from each other at a divergent boundary. 14. Mid ocean ridge Ridges that form in the middle of the ocean floor when two oceanic plates move away from each other at a divergent boundary. 15. Island arc A chain of volcanic islands that form when to oceanic plates move toward each other at convergent boundaries 16. Deep sea trench A deep valley made on the ocean floor when a continental and oceanic plate converge and the oceanic plate subducts under the continental plate. 17. Magnetic symmetry This is when the magnetic field of the earth is recorded in the ocean floor. It is used as evidence that the ocean is spreading apart. 18. Geochronology Means ground order. When aging the ocean floor, the youngest is near the mid ocean ridges and progressively gets older as you go away from the ridge. 19. Subduction When one plate goes underneath another plate 20. Convection When hot liquids rise and cool liquids fall in a circular motion. 21. Transform boundary When two boundaries moves side by side. 22. Plate tectonics the theory that explains that the structures on the earth (i.e. mountains) are made by the interactions of earths plates when they move, because of convection in the mantle. 23. Pangaea the last super continent before our current continents broke apart. 24. Sea floor spreading the theory that the sea floor is spreading part from the middle, creating new sea floor there, 25. The Ring of Fire the area around the Pacific Ocean that is extremely active with volcanoes and earthquakes.

3 #3 Earth Quake map

4 Earth s Interior LT 4.1 Earth s Interior: I can draw and interpret models of the interior of the earth. #4

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6 LT 4.1 Earth s Interior: I can draw and interpret models of the interior of the earth. Model of the Earth #6 Earth is made up of 3 compositional layers and 5 structural layers. These layers overlap within the Earth. So you can have a nice model, you will be making your own diagram of the Earth s interior. Compositional (Chemical Structural (physical properties are different) properties) Layer Depth from Scale (cm) Layer Depth from Scale (cm) surface (miles) surface (miles) Crust 0-22 Lithosphere 0-37 Mantle 22-1,790 Asthenosphere Core Mesosphere Outer core Inner Core Questions 1. Describe how scientists found out that Earth had internal layers. 2. Describe the layers a. Lithosphere - b. Asthenosphere - c. Mesosphere - d. Outer Core - e. Inner Core - 3. Which layers are made of iron and nickel? 4. Describe why scientists believe there is a magnetic field (magnetosphere) around the Earth.

7 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. #7 Discovering Plate Boundaries You have been (or will be) assigned to one of four Scientific Specialties and to one of ten Plates or Plate Groupings. The Scientific Specialties are: A. Seismology B. Volcanology C. Geography D. Geochronology Assemble in your Scientific Specialty groups with your group's map Task 1 Make observations about your map. What are some patterns that you see? During this period concentrate on the whole world, not just your assigned plate (if you know what it is). Task 2 Now focus your attention on the plate boundaries. Identify patterns that you see at plate boundaries. As a group, classify the plate boundaries based on your observations of your group's data (have at least 2-3 types of plate boundaries). Restrict yourselves to about 4-5 boundary types. Task 3 Assign a colored pencil color to each boundary type in your classification scheme. Each person should write down descriptions of the group's plate boundary classifications on the back of their map. What Patterns do you notice for each of the following maps: 1. Semiology 2. Volcanoes 3. Geography 4. Geochronology

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9 #9 LT 4.2 Plate tectonics: I can explain the evolution of tectonic theory, the evidence used to develop the theory, and a possible mechanism for plate motion. Plate Tectonics Notes Some science stuff you should know: Hypothesis: Educated guess (based on something but not necessarily well supported) Theory: supported with lots of evidence (Where Gravity comes from is a theory) Law: describes the relationship of things (The Law of gravity: how strong is the pull of the earth) CONTINENTAL DRIFT Alfred Wegener in the early 1900 s proposed the hypothesis that continents were once joined together in a single large land mass he called Pangea (meaning all land in Greek). He proposed that Pangea had split apart and the continents had moved gradually to their present positions - a process that became known as continental drift. Evidence of Continental Drift/Plate tectonics 1. Continents look like they fit together 2. Fossil evidence 3. Rock formations 4. Climate evidence 5. Sea floor spreading 6. Magnetic symmetry 1. Continents look like they fit together Continents fit together like a puzzle.e.g. the Atlantic coastlines of Africa and South America. The Best fit includes the continental shelves (the continental edges under water.) 2. Fossil evidence Fossils of plants and animals of the same species found on different continents. 3. Rock Formations Matching mountain ranges across oceans

10 4. Climate Glacial ages and climate evidence Evidence of glaciers were temperatures are too warm today Fossils of tropical plants in Antarctica #10 5. Seafloor Spreading Mountains on the ocean floor were magma was coming to the surface (rift) New ocean floor is made in the middle 6. Magnetic symmetry Magnetic field changes are recorded in new rock Symmetrical magnet rock are formed because the floor is spreading Magnetic symmetry Draw what ocean floor looks like below: CONTINENTAL DRIFT vs. PLATE TECTONICS No one believed Alfred Wegener because he could not explain how it work The Theory of Plate Tectonics is the hypothesis of continental drift with an explanation CONTINENTAL DRIFT Evidence for Continental Drift 1. Continents look like they fit together 2. Fossil evidence 3. Rock formations 4. Climate evidence 5. Sea floor spreading 6. Magnetic symmetry Explanation:????????????????? PLATE TECTONICS Evidence for Plate tectonics 1. Continents look like they fit together 2. Fossil evidence 3. Rock formations 4. Climate evidence 5. Sea floor spreading 6. Magnetic symmetry Explanation: Convection

11 #11 LT 4.2 Plate tectonics: I can explain the evolution of tectonic theory, the evidence used to develop the theory, and a possible mechanism for plate motion. 1. What is the scientific definition of convection? We are going to observe three different examples of convection. Please describe each below: Observation #1 Observation #2 Observation #3 2. Draw general what is happening during convection. Label where it is hot and where it is cold. 3. What is your definition for convection?

12 #12 LT 4.2 Plate tectonics: I can explain the evolution of tectonic theory, the evidence used to develop the theory, and a possible mechanism for plate motion. Make your own Pangaea Map 1. On a piece of plane paper, draw an island with a somewhat random shape (don t make a circle or and oval). It should take up most of the paper. 2. Use the symbol for mountains and draw 3 lines of mountains anywhere on your island. 3. Use the symbol for a dinosaur fossil and draw several of them in one area of your island. 4. Use the symbol for a freshwater reptile footprint and draw several of them in one area of your island. 5. Use the symbol for a pinecone fossil and draw several of them in one area of your island. 6. Pick a color for each of previous for steps and shade them. 7. Shade the coast of your island yellow to represent the beach. 8. Cut your island into 6-10 pieces. Make your cuts so that go through the features you made. Each piece should have at least one clue on it clue on it. 9. Give your pieces to another student for them to put together. Key: Example (don t copy mine, do your own!)

13 #13 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. Comparing Crust 1. You are going to be given two samples of rock. Take as many observations of each as you can: Type Granite (Continental) Basalt (Oceanic) Observations 2. We are going to calculate the densities of each. The group closest to the correct answer wins! Show your work below: 3. To summarize what we need to know, we are going to fill the chart below. You will need to know and be able to explain this table! Type Continental Oceanic Type of Rock Location Size Composition Age Density

14 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. #14 Name of Plate boundary Plate Movement Plate tectonics Go to this page: Go to the Plate Motion tab and set up the following scenarios. 1. Using the figure above, first name the type of crust at the boundary and second, name the type of boundary. A. Continental Continental convergent, C-C convergent B. C. D. E. A Island arch Volcano Subduction Rift Valley Trench Mid-ocean Ridge Mountains B C D E

15 #15 Type of Margin Motion Divergent Convergent Transform What it makes Volcanoes? Earthquakes?

16 #16 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. Hotspots Go to the Hot Spot page and draw a picture of what is happening. Label the youngest island and which is the oldest. Also predict where the next island would be. Below is a map of the Hawaiian island chain. Try to recreate it (draw it) in the box to the right. To do this, you cannot move your pencil (the hot spot) move only the paper (the plate). Start here End here 1. What pattern do you notice about the age of the islands? 2. What direction did you have to start moving the paper? 3. What happened about half way through? 4. What direction was the Pacific plate moving when the islands were first formed? 5. What direction is it moving now? Below, describe the motion of each plate to make the island chains that we see. Start Today Start Today Start Today Start Today

17 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. Hotspots #17 Using the data below, we are going to determine how fast the plate is moving. Island Distance from Hot spot Age Rate Hawaii 42 km 0.4 my km/my Necker 1059 km 10.3 my Midway 2432 km 27.7 my Abbott 3280 km 38.7 my Koko 3758 km 48.1 my Nintoko 4452 km 56.2 my Suiko 4860 km 64.7 my 1. How fast is the Plate moving now? 2. How fast was the plate moving when the first islands were formed? 3. Has the plate sped up or slowed down? 4. Looking at the picture on the previous page, about how long ago did the plate change direction? 5. Look at the picture below. This is the hotspot that is under Yellowstone national park that some people refer to as a super volcano. Where is the hotspot currently located? 6. What direction is the plate moving?

18 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. #18

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20 #20 LT 4.3 Surface Features: I can model surface features of the earth due to plate tectonics. Plate Tectonics Stations Lab Answer the following questions when you are at each station Station 1: Seismology: At what type of boundary do deep earthquakes happen? Station 2: Volcanoes: At what type of boundary do volcanoes happen? Station 3: Geochronology: What type of boundary does young crust exist? Station 4: Geography: What type of boundary do trenches and mountains exist? Station 5: Continental-oceanic crust collision: In the space below, Draw and label the picture you see at your table (It does not need to be perfect.) Station 6: Oceanic-Oceanic crust collision: In the space below, Draw and label the picture you see at your table (It does not need to be perfect.) Station 7: Continental-Continental crust collision: In the space below, Draw and label the picture you see at your table (It does not need to be perfect.)