1. The Theory of Plate Tectonics

2. Expected Learning Explain the theory of plate tectonics Describe the three types of plate boundaries. Explain the theory of plate tectonics Describe the three types of plate boundaries.

3. Lesson work Go through this Powerpoint. Watch the Rich Tea tectonics video, and write a brief description of what the video is demonstrating and how From the tectonics document complete questions 1, 2, 3, 4, 5, 6, 13, 14, 15, 22, 27, 31, 32, 34, 36 and 38 in your book

4. Engage/Explore What is a plate? Think of other contexts in which the word is used. Metal plates that cover machinery Home plate in baseball, a reptile’s plates or scales plate of photographs in a textbook What is a plate? Think of other contexts in which the word is used. Metal plates that cover machinery Home plate in baseball, a reptile’s plates or scales plate of photographs in a textbook

5. Introduction J. Tuzo Wilson - Canadian scientist. He discovered that there are cracks in the continents similar to those on the ocean floor. J. Tuzo Wilson - Canadian scientist. He discovered that there are cracks in the continents similar to those on the ocean floor.

6. Wilson proposed that the lithosphere is broken into separate sections called plates. Plates can carry both continents or parts of the ocean floor. Wilson proposed that the lithosphere is broken into separate sections called plates. Plates can carry both continents or parts of the ocean floor.

7. Great Rift Valley in East Africa

8. A Theory of Plate Motion Wilson combined the thoughts of sea-floor spreading, Earth’s plates, and continental drift into a theory. A scientific theory is a well-tested concept that explains a wide range of observations. Wilson combined the thoughts of sea-floor spreading, Earth’s plates, and continental drift into a theory. A scientific theory is a well-tested concept that explains a wide range of observations.

9. Plate tectonics is the geological theory that state that pieces of Earth’s lithosphere are in constant, slow motion, driven by convection currents in the mantle. It explains the formation, movement, and subduction of Earth’s plates.

10. How can Earth’s plates move? The plates of the lithosphere float on top of the asthenosphere. Convection currents rise in the asthenosphere and spread out beneath the lithosphere.

11. Earth’s Lithospheric Plates

12. Affects of the plates Collide Pull apart Grind past each other Collide Pull apart Grind past each other Volcanoes Mountain ranges Deep-sea trenches Volcanoes Mountain ranges Deep-sea trenches

13. Plate Boundaries Faults - breaks the Earth’s crust where rocks have slipped past each other which form along these boundaries. Three kinds of boundaries Faults - breaks the Earth’s crust where rocks have slipped past each other which form along these boundaries. Three kinds of boundaries

14. Transform Boundary A place where two plates slip past each other, moving in opposite directions. Earthquakes occur along these boundaries. San Andreas Fault is an example. The Pacific plate is sliding past the North American plate. Crust is neither created nor destroyed. A place where two plates slip past each other, moving in opposite directions. Earthquakes occur along these boundaries. San Andreas Fault is an example. The Pacific plate is sliding past the North American plate. Crust is neither created nor destroyed.

15. San Andreas Fault

17. Divergent Boundary The place where two plates move apart. Most occur at the mid-ocean ridge and on land. The boundary forms rift valleys. Example - Great Rift Valley has a 3000 km crack. The place where two plates move apart. Most occur at the mid-ocean ridge and on land. The boundary forms rift valleys. Example - Great Rift Valley has a 3000 km crack.

18. Rio Grande Rift Extends from central Colorado to El Paso, Texas. Extends from central Colorado to El Paso, Texas.

19. Convergent Boundaries Two plates come together. This is called a collision When two continental plates collide, why isn’t one subducted beneath the other? Appalachian Mountains formed when two continental plates collided. -The density of plates determines which plate comes out on top. Two plates come together. This is called a collision When two continental plates collide, why isn’t one subducted beneath the other? Appalachian Mountains formed when two continental plates collided. -The density of plates determines which plate comes out on top.

20. Appalachian Mountains

21. Convergent Boundaries Oceanic/oceanicSubduction occurs Oceanic/continentalOceanic plate sinks Continental/continentalMountain ranges form

22. Lesson work reminder Go through this Powerpoint. Watch the Rich Tea tectonics video, and write a brief description of what the video is demonstrating and how From the tectonics document complete questions 1, 2, 3, 4, 5, 6, 13, 14, 15, 22, 27, 31, 32, 34, 36 and 38 in your book