1 / 38

PLATE TECTONICS

PLATE TECTONICS. Earth’s tectonic plates. Arrows indicate the direction of movement. 1.2. Continents change position over time. Gravity and motions in the asthenosphere move tectonic plates over Earth’s surface. continental drift. Pangaea. mid-ocean ridge. convection. convection current.

cybill
Download Presentation

PLATE TECTONICS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PLATE TECTONICS

  2. Earth’s tectonic plates. Arrows indicate the direction of movement. 1.2 Continents change position over time. Gravity and motions in the asthenosphere move tectonic plates over Earth’s surface. continental drift Pangaea mid-ocean ridge convection convection current theory of plate tectonics CHAPTER RESOURCES SECTION OUTLINE

  3. 1.2 Continents change position over time. • Plates move at very slow rates—from about one to ten centimeters per year. • At one time in geologic history the continents were joined together in one large landmass called Pangaea. • As the plates continued to move and split apart, oceans were formed, landmasses collided and split apart until Earth’s landmasses came to be in the positions they are now. continental drift Pangaea mid-ocean ridge convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  4. 1.2 Continents change position over time. • Evidence of these landmass collisions and splits comes from fossils, landform shape, features, and rock structures, along with climate change. • Landmass changes can occur at hot spots within lithospheric plates. • Earth’s landmasses will continue to move and change during the geologic time of the future. continental drift Pangaea mid-ocean ridge convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  5. continental drift 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge The hypothesis that Earth’s continents move on Earth’s surface. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  6. Pangaea 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge A hypothetical supercontinent that included all of the landmasses on Earth. It began breaking apart about 200 million years ago. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  7. mid-ocean ridge 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge A long line of sea-floor mountains where new ocean crust is formed by volcanic activity along a divergent boundary. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  8. convection 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge A process by which energy is transferred in gases and liquids, occurring when a warmer, less dense area of gas or liquid is pushed up by a cooler, more dense area of the gas or liquid. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  9. convection current 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge A circulation pattern in which material is heated and rises in one area, then cools and sinks in another area, flowing in a continuous loop. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  10. theory of plate tectonics 1.2 Continents change position over time. continental drift Pangaea mid-ocean ridge A theory stating that Earth’s lithosphere is broken into huge plates that move and change in size over time. convection convection current theory of plate tectonics CHAPTER RESOURCES KEY CONCEPT SUMMARY

  11. 1.3 Plates move apart. New crust is formed at divergent boundaries. Features include: divergent boundary • mid-ocean ridges convergent boundary transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES SECTION OUTLINE

  12. 1.3 Plates move apart. New crust is formed at divergent boundaries. Features include: divergent boundary • mid-ocean ridges • records of magnetic reversals convergent boundary transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES SECTION OUTLINE

  13. 1.3 Plates move apart. New crust is formed at divergent boundaries. Features include: divergent boundary • mid-ocean ridges • records of magnetic reversals convergent boundary • rift valleys transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES SECTION OUTLINE

  14. VISUALIZATION CLASSZONE.COM Explore what happens along plate boundaries. 1.3 Plates move apart. New crust is formed at divergent boundaries. Features include: divergent boundary • mid-ocean ridges • records of magnetic reversals convergent boundary • rift valleys transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES SECTION OUTLINE

  15. divergent boundary 1.3 Plates move apart. divergent boundary convergent boundary • Where two plates are moving apart. • Most are located along the mid-oceanic ridge (sea-floor spreading). • New crust forms because magma pushes up and hardens between separating plates. • Characterized by either a mid-ocean ridge or a continental rift valley. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  16. convergent boundary 1.3 Plates move apart. divergent boundary convergent boundary • Where two plates come together and collide. • Activity depends upon the types of crust that meet. • A more dense oceanic plate slides under a less dense continental plate or another oceanic plate—this is called a subduction zone, and some crust is destroyed during this type of activity. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  17. transform boundary 1.3 Plates move apart. divergent boundary convergent boundary • Where two plates slide past each other. • Crust is neither created or destroyed at this type of boundary. • Earthquakes occur frequently along this type of boundary. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  18. rift valley 1.3 Plates move apart. divergent boundary convergent boundary A deep valley formed as tectonic plates move apart, such as along a mid-ocean ridge. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  19. magnetic reversal 1.3 Plates move apart. divergent boundary convergent boundary A switch in the direction of Earth’s magnetic field so that the magnetic north pole becomes the magnetic south pole and the magnetic south pole becomes the magnetic north pole. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  20. hot spot 1.3 Plates move apart. divergent boundary convergent boundary An area where a column of hot material rises from deep within a planet’s mantle and heats the lithosphere above it, often causing volcanic activity at the surface. transform boundary rift valley magnetic reversal hot spot CHAPTER RESOURCES KEY CONCEPT SUMMARY

  21. 1.4 Plates converge or scrape past each other. Crust is destroyed or folded at convergent boundaries. • Subduction boundaries form island arcs, deep-ocean trenches, and coastal mountains. subduction continental-continental collision • Collision boundaries can form mountains. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES SECTION OUTLINE

  22. 1.4 Plates converge or scrape past each other. Crust is destroyed or folded at convergent boundaries. • Subduction boundaries form island arcs, deep-ocean trenches, and coastal mountains. subduction continental-continental collision • Collision boundaries can form mountains. Crust is neither formed nor destroyed at transform boundaries. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES SECTION OUTLINE

  23. subduction KEY CONCEPT SUMMARY 1.4 Plates converge or scrape past each other. subduction continental-continental collision The process by which an oceanic tectonic plate sinks under another plate into Earth’s mantle. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES

  24. continental-continental collision 1.4 Plates converge or scrape past each other. subduction continental-continental collision A boundary along which two plates carrying continental crust push together. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES KEY CONCEPT SUMMARY

  25. oceanic-oceanic subduction 1.4 Plates converge or scrape past each other. subduction continental-continental collision A boundary along which a plate carrying oceanic crust sinks beneath another plate with oceanic crust. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES KEY CONCEPT SUMMARY

  26. oceanic-continental subduction 1.4 Plates converge or scrape past each other. subduction continental-continental collision A boundary along which a plate carrying oceanic crust sinks beneath a plate with continental crust. oceanic-oceanic subduction oceanic-continental subduction CHAPTER RESOURCES KEY CONCEPT SUMMARY

  27. 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. • http://www.pbs.org/wgbh/aso/tryit/tectonics/# vocanic eruptions mountain-building forces • http://www.pbs.org/wnet/savageearth/animations/volcanoes/index.html stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  28. Volcanic Eruptions: 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Volcanic eruptions are constructive in that they add new rock to existing land and form new islands. • Magma from the mantle rises to Earth’s surface and flows out an opening called a vent. • Magma that reaches Earth’s surface is known as lava. • The vent as well as the mountain that forms around is from the cooled lava, ash, cinders, and rock is called a volcano. • Most volcanoes occur along plate boundaries; • An area in the Pacific Ocean where volcanoes are common is called the Ring of Fire. mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  29. Mountain-Building Forces 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Forces or stresses (for example, tension and compression) on rocks in the lithosphere can cause them to bend and stretch. • This bending and stretching can produce mountain ranges. • If pressure is applied slowly, folded mountains form. • Fast pressure=high peak mountains (The Himalayan Mountains) • Slow pressure=folded mountains (they look like a hood of a car after a wreck, and an example are the Appalachian Mountains. mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  30. Stresses: 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Forces or stresses (for example, tension, compression, or shearing) great enough to cause rocks to break can create faults. • There are three types of faults. mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  31. Normal Faults: 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Caused by tension forces. • Happen where the lithosphere is being stretched. • Usually occur at divergent boundaries. • If normal faults uplift a block of rock, a fault-block mountain forms. mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  32. Reverse Faults: 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Caused by compression forces. • Causes shortening of the crust. • Occurs most frequently at convergent boundaries. mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  33. Strike-Slip Faults: 1.5 The landforms of Earth can be changed by volcanic eruptions and mountain-building forces. vocanic eruptions • Caused by shearing forces. • Occur most often at transform boundaries. • Example of fault: the San Andreas Fault • http://www.iris.edu/gifs/animations/faults.htm mountain-building forces stresses normal fault reverse fault strike-slip fault CHAPTER RESOURCES KEY CONCEPT SUMMARY

  34. 1.1 Earth has several layers. I. Earth has several layers. inner core A. Earth is made up of materials with different densities. outer core mantle B. Earth’s layers have different properties. crust 1. Core, Mantle, Crust lithosphere C. The lithosphere is made up of many plates. asthenosphere tectonic plate CHAPTER RESOURCES KEY CONCEPT SUMMARY

  35. 1.2 Continents change position over time. II. Continents change position over time. continental drift A. Continents join together and split apart. Pangaea 1. Evidence for Continental Drift mid-ocean ridge 2. Pangaea and Continental Drift convection convection current B. The theory of plate tectonics explains how plates and their continents move. theory of plate tectonics 1. Evidence from the Sea Floor 2. Causes of Plate Movement CHAPTER RESOURCES 3. Putting the Theory Together KEY CONCEPT SUMMARY

  36. 1.3 Plates move apart. III. Plates move apart. divergent boundary A. Tectonic plates have different boundaries. convergent boundary B. The sea floor spreads apart at divergent boundaries. transform boundary 1. Mid-Ocean Ridges and Rift Valleys rift valley 2. Sea-Floor Rock and Magnetic Reversals magnetic reversal C. Continents split apart at divergent boundaries. hot spot D. Hot spots can be used to track plate movements. CHAPTER RESOURCES KEY CONCEPT SUMMARY

  37. 1.4 Plates converge or scrape past each other. IV. Plates converge or scrape past each other. subduction A. Tectonic plates push together at convergent boundaries. continental-continental collision 1. Continental-Continental Collision 2. Oceanic-Oceanic Subduction oceanic-oceanic subduction 3. Oceanic-Continental Subduction oceanic-continental subduction B. Tectonic plates scrape past each other at transform boundaries. C. The theory of plate tectonics helps geologists today. CHAPTER RESOURCES KEY CONCEPT SUMMARY

  38. CLASSZONE.COM CHAPTER HOME Chapter Resources Image Gallery Click here to review chapter images and animations Review Game Play a fun interactive review game Animations Link to all the McDougal Littell Science animations Click on the items below to access resources on Resource Centers Get more information on select science topics Audio Readings Hear chapter audio readings Content Review Review key concepts and vocabulary Standardized Test Practice Practice state standardized tests Math Tutorial Review math concepts BACK TO CHAPTER

More Related