Continental Drift Theory

1. Continental Drift Theory • Alfred Wegener • German meteorologist • 1912 Proposed Pangaea and Continental Drift Theory

2. Continental Drift Theory1912 Wegener 5 Types of Evidence http://library.thinkquest.org/3669/media/map2dd.GIF

3. Evidence of Pangaea • Continents ‘fit’ together • CLICK Simulations http://www.ucmp.berkeley.edu/geology/anim1.html http://www.eoearth.org/upload/thumb/f/fb/Plate_tectonics_over_time.gif/400px-Plate_tectonics_over_time.gif

4. Evidence- Plant and Animal Fossil Distribution

5. Evidence – Similar sequence of rock or Rock formations have same age

6. Glacial Evidence- deposits, striations, scraping patterns

7. Evidence - Climate distribution Past Present

8. Wegener’s Theory Problems • Continents plowing through the crust would destroy the crust, no real “forces” explaining why. • Continents are not moving apart at the speed Wegener proposed

9. Holmes Convection Currents

10. Convection currents • Gravity causes the heated mantle to sink • The mantle heats up near the core and then rises again • Conduction is the transfer of heat between 2 materials in direct contact with each other library.thinkquest.org/C003124/images/convect.jpg http://www.wisc-online.com/objects/index_tj.asp?objID=SCE304 Click animation

11. Magnetic field changes over time Evidence - Magnetic pattern of rock

12. North Magnetic Pole in No. Hemi

13. North Magnetic Pole in So. Hemi

14. Present DayNorth Magnetic Pole in No. Hemi

15. Sea-Floor Spreading Hypothesis by Hess & Deitz CLICK Animation: http://www.uwsp.edu/geo/faculty/ritter/glossary/s_u/sea_flr_spread.html

16. Plate Tectonics Floating on Asthenosphere Plates have oceanic and continental crust www.wiley.com/college/herenow/ptect/pt-map1.gif

17. Earth’s Layers • Inner Core • Outer Core • Mantle • Crust • Atmosphere • Asthenosphere and Lithosphere location http://library.thinkquest.org/04oct/01724/images/Earth-crust-cutaway-english.png

18. Continental Crust • Cooling rate • Crystal size • Density • Composition • Thickness http://www.amonline.net.au/geoscience/images/earth_diagrams/cont_oceanic_crust.gif

19. Oceanic Crust • Cooling rate • Crystal size • Density • Composition • Thickness http://faculty.weber.edu/bdattilo/parks/plume_ocean.jpg

20. Volcano http://cgz.e2bn.net/e2bn/leas/c99/schools/cgz/accounts/staff/rchambers/GeoBytes%20GCSE%20Bl og%20Resources/Images/Plate%20Tectonics/Plate%20Tectonics/VolcanoStructure.jpg

21. Earthquake • http://news.bbc.co.uk/nol/shared/spl/hi/world/04/earthquake/img/earthquake.gif

22. Evidence- Location of mountain ridges, rifts, mid-ocean ridges, trenches on plate boundaries http://www.ifa.hawaii.edu/~barnes/ast110_06/tprai/Tectonic_plate_boundaries.png SIMULATIONS ON ALL BOUNDARY TYPES CLICK http://www.pbs.org/wgbh/aso/tryit/tectonics/shockwave.html

23. Andes MountainsConvergent Oceanic & Continental blue.utb.edu/paullgj/images/Conv_Cont_Ocean.JPG CLICK http://www.pbs.org/wgbh/aso/tryit/tectonics/convergent.html

24. Convergent BoundaryOceanic & Continental CLICK http://geology.com/nsta/convergent-boundary-oceanic-continental.gif http://geology.com/nsta/plate-tectonics-cover.gif

25. Japan or Aleutian IslandsConvergent Oceanic & Oceanic ceeps.colostate-pueblo.edu/.../smM1P1Fig15.gif

26. Convergent BoundaryOceanic & Oceanic http://geology.com/nsta/convergent-boundary-oceanic-oceanic.gif

27. HimalayasConvergent Continental & Continental CLICK Convergent Simulation http://www.pbs.org/wgbh/aso/tryit/tectonics/crush.html

28. Convergent BoundaryContinental & Continental http://geology.com/nsta/convergent-boundary.gif

29. http://www.odp.usyd.edu.au/odp_CD/sr/images/textpics/Fig7.gif Mid Atlantic RidgeDivergent Oceanic DIVERGENT SIMULATIONS CLICK http://geology.com/plate-tectonics.shtml CLICK http://www.pbs.org/wgbh/aso/tryit/tectonics/divergent.html

30. Divergent BoundaryOceanic • Sea-floor spreading, Mid-Ocean Ridges CLICK http://geology.com/nsta/divergent-boundary-oceanic.gif

31. East African Rift ValleyDivergent Continental ceeps.colostate-pueblo.edu/.../smM1P1Fig15.gif

32. Divergent BoundaryContinental • Rift Valley http://geology.com/nsta/divergent-boundary-continental.gif

33. San Andreas FaultTransform Boundary www.wiley.com/college/herenow/ptect/pt-map1.gif

34. Transform Boundary TRANSFORM SIMUALTIONS CLICK http://geology.com/nsta/transform-boundary.gif CLICK http://www.pbs.org/wgbh/aso/tryit/tectonics/transform.htm

35. http://vulcan.wr.usgs.gov/Imgs/Gif/PlateTectonics/Maps/map_plate_tectonics_world.gifhttp://vulcan.wr.usgs.gov/Imgs/Gif/PlateTectonics/Maps/map_plate_tectonics_world.gif Evidence - Location of earthquakes and volcanoes

37. Hot Spots – Hawaiian Islands http://geology.com/nsta/plate-tectonics-cover.gif

38. The Hawaiian - Emperor Volcanic Chain

39. Location of Hot Spots

40. Plate Movement in the future • http://www.scotese.com/earth.htm

41. External Energy For Earth • Sun & Moon keeps air and sea in motion, shapes surface • Sun warms atmosphere & crust unevenly creating winds • Winds drive ocean currents and water cycle • Erosion from winds, rains, rivers, glaciers, and waves shape surface • Weathering from winds and rains • Sun & Moon Gravitational Energy, produces tides • Planetesimal collisions

42. Internal Energy for Earth • Radioactive element decay • Core heat from layers pressure • Convection currents • Volcanoes • Hot Springs • Earthquakes

43. Evidence for Plate Tectonics • Continents fit together • Fossil distribution • Glacier evidence: deposits, striations, scraping • Climate distribution • Common rock formations: same age • Magnetic pattern of rock • Location of earthquakes and volcanoes • Location of mountain ridges, rifts, mid-ocean ridges, trenches