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Chapter 2.1 Plate Tectonics

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  • + Aspevik Aspevik 1 month ago
    I have solved the problems around Alfred Wegener`s theory who have been discussed since 1911.

    22 August 1998, Jeff Hecht wrote an article in New Scientist who proves that AlfredWegeners Theory is wrong. Here is this article:

    quote: “Magnetic shift

    By Jeff Hecht

    TRACES of the earth’s magnetic field frozen in rocks are yielding surprises about the planet’s past. A re-analysis of old measurements of these fields has forced geologists to conclude that either the migrating continents were clustered closer to the equator than previously thought, or that the Earth’s magnetic field was not the simple pair of poles it is today.

    Geologists track the history of continental motion by measuring the magnetism of ancient rocks. As some rocks form, they retain an imprint of the Earth’s magnetic field. The field direction and the age of the rock together show the latitude of the continent at the time the rock formed, provided that the shape of the terrestrial magnetic field at the time can be worked out.

    Today, the Earth’s magnetic field lines, which emanate from the poles and surround the planet, have a simple and predictable distribution. Geologists have proved that for at least five million years the field has been a dipole, like a bar magnet with poles aligned on the planet’s axis. And they calculate ancient latitudes assuming the field has always been a dipole, says Dennis Kent of the Lamont-Doherty Earth Observatory in Palisades, New York.

    But now Kent and Mark Smethurst of the Geological Survey of Norway in Trondheim have analysed palaeomagnetic data from rocks up to 3·5 billion years old. Instead of the magnetic distribution expected from a dipole, they found an excess of rocks from older eras with low-angle fields, as if they had formed at lower latitudes than those predicted by standard models that assume a random distribution of the early continents (Earth and Planetary Science Letters, vol 160, p 391). 'The surprising result is that in the Palaeozoic and Precambrian, the distributions differ markedly,' Kent says.

    One possible explanation is that the Earth’s magnetic field has not always been a dipole. Kent calculates that if the ancient Earth contained elements of between four and eight poles, its magnetic field lines would have met the migrating continents at lower angles than the lines of the modern dipole field. That would account for the distribution he and Smethurst observed, he says. Such an arrangement might have been possible before the solid part of the core--which started growing as late as a billion years ago--reached its present size.

    The other possible explanation for the findings, Kent says, is that the continents were once clustered near the equator. Such clustering could be the result of centrifugal force tilting heavy parts of the outer layers of the Earth away from the poles (' Twist of fate ', New Scientist, 2 August 1997, p 15).

    Gary Glatzmaier of the Los Alamos National Laboratory in New Mexico says his unpublished simulations of the Earth’s magnetic field may be able to discover which explanation is right. According to his models, multiple poles are unlikely, he says. 'When the inner core was smaller, our simulations suggest the dipole was even stronger than today.' If correct, Glatzmaier’s results would mean that geologists have to redraw their maps of the ancient continents.”

    From New Scientist, 22 August 1998

    Proof should, as the article shows, make the geologists want to re-evaluate the foundations they build their authority upon. Particularly because this earlier model is being taught in Universities and Schools. In my estimation, we have a responsibility that we can not neglect when it comes to correct research theories that obviously do not hold good.

    Even though this is only a theory, we must be willing to re-evaluate old theories when new scientific elements come to light that prove that the former theory no longer holds good.

    Unfortunately, the tendency is that man will reject new thinking, when after a while one has built his whole research upon this one special model. In hopes that my private theory might result in an intelligent discussion, I hereby would like to present my work.

    Each individual reader is encouraged and invited to judge the results for themselves.

    Good luck!!

    Take a look at my home page where I have studied the issue for over 20 years.

    You find my work here: http://aspevik.net

    Helge Aspevik
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Chapter 2.1 Plate Tectonics - Presentation Transcript

  1. Chapter 2: Plate Tectonics
  2. Layers of the Earth
  3. Layers of the Earth Denser Basaltic Rocks
  4. Layers of the Earth Denser Less dense Basaltic Granitic Rocks Rocks
  5. Alfred Wegener’s Continental Drift Theory
  6. Evidences
  7. Evidences
  8. Evidences
  9. Evidences • Geological Evidence: Edges of continents fit like a jig-saw
  10. Evidences • Geological Evidence: Edges of continents fit like a jig-saw • Biological Evidence: Fossils & Imprints of plants
  11. Evidences • Geological Evidence: Edges of continents fit like a jig-saw • Biological Evidence: Fossils & Imprints of plants • Climate Based Evidence: Glaciation
  12. So does our earth still move today?
  13. So does our earth still move today? How will earth look like in the future?
  14. What’s wrong with Wegener’s theory of Continental Drift?
  15. What’s wrong with Wegener’s theory of Continental Drift?
  16. What’s wrong with Wegener’s theory of Continental Drift? • Continents do NOT move.
  17. What’s wrong with Wegener’s theory of Continental Drift? • Continents do NOT move. • It is the tectonic (crustal) plates that consist of both oceanic and continental crusts that moves.
  18. Tectonic Plates vs. Plate Tectonics
  19. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates:
  20. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates: • Consist of both continental and oceanic crusts.
  21. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates: • Consist of both continental and oceanic crusts. • Plate Tectonics:
  22. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates: • Consist of both continental and oceanic crusts. • Plate Tectonics: • How plates move
  23. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates: • Consist of both continental and oceanic crusts. • Plate Tectonics: • How plates move • Why they move
  24. Tectonic Plates vs. Plate Tectonics • Tectonic (Crustal) Plates: • Consist of both continental and oceanic crusts. • Plate Tectonics: • How plates move • Why they move • How the movement changes the physical landscape
  25. Memorise!
  26. Plate Boundaries & Movements
  27. Plate Boundaries & Movements • 1. Constructive plate boundaries
  28. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart)
  29. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force
  30. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries
  31. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries • Convergent (Move towards)
  32. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries • Convergent (Move towards) • Compressional force
  33. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries • Convergent (Move towards) • Compressional force • 3. Conservative plate boundaries
  34. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries • Convergent (Move towards) • Compressional force • 3. Conservative plate boundaries • Transform (Slide past)
  35. Plate Boundaries & Movements • 1. Constructive plate boundaries • Divergent (Move apart) • Tensional force • 2. Destructive plate boundaries • Convergent (Move towards) • Compressional force • 3. Conservative plate boundaries • Transform (Slide past) • Frictional force
  36. Physical features in the World
  37. Physical features in the World Mid-Atlantic Ridge
  38. Physical features in the World East African Rift Valley Mid-Atlantic Ridge
  39. Physical features in the World East African Rift Valley Andes Mid-Atlantic Ridge
  40. Physical features in the World Rockies East African Rift Valley Andes Mid-Atlantic Ridge
  41. Physical features in the World Himalayas Rockies East African Rift Valley Andes Mid-Atlantic Ridge
  42. Physical features in the World St. Andrea’s Fault Himalayas Rockies East African Rift Valley Andes Mid-Atlantic Ridge
  43. 1. Constructive Plate Boundaries Sea Floor Spreading Plates diverges & pulls apart
  44. 1. Constructive Plate Boundaries
  45. 1. Constructive Plate Boundaries
  46. 1. Constructive Plate Boundaries • Case #1: Oceanic-Oceanic Crusts
  47. 1. Constructive Plate Boundaries • Case #1: Oceanic-Oceanic Crusts • Ridges.
  48. 1. Constructive Plate Boundaries • Case #1: Oceanic-Oceanic Crusts • Ridges. • Eg. Mid-Atlantic Ridge
  49. 1. Constructive Plate Boundaries • Case #1: Oceanic-Oceanic Crusts • Ridges. • Eg. Mid-Atlantic Ridge • Sometimes lava fountains are found in the middle of the ridges.
  50. 1. Constructive Plate Boundaries
  51. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts
  52. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts
  53. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts • Rift Valleys
  54. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts • Rift Valleys • Eg. East African Rift Valley
  55. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts • Rift Valleys • Eg. East African Rift Valley • Magma rises and squeezes through the widening cracks, sometimes to erupt and form volcanoes.
  56. 1. Constructive Plate Boundaries • Case #2: Continental- Continental Crusts • Rift Valleys • Eg. East African Rift Valley • Magma rises and squeezes through the widening cracks, sometimes to erupt and form volcanoes. • The rising magma puts more pressure on the crust to produce additional fractures and, ultimately, the rift zone.
  57. 2. Destructive Plate Boundaries Plates converges & collide
  58. 2. Destructive Plate Boundaries
  59. 2. Destructive Plate Boundaries
  60. 2. Destructive Plate Boundaries
  61. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts
  62. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains
  63. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes
  64. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes • Trench
  65. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes • Trench • Eg. Peru-Chile Trench
  66. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes • Trench • Eg. Peru-Chile Trench • Earthquakes
  67. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes • Trench • Eg. Peru-Chile Trench • Earthquakes
  68. 2. Destructive Plate Boundaries • Case #1: Oceanic-Continental Crusts • Mountains • Eg. Andes • Trench • Eg. Peru-Chile Trench • Earthquakes
  69. 2. Destructive Plate Boundaries
  70. 2. Destructive Plate Boundaries
  71. 2. Destructive Plate Boundaries
  72. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts
  73. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts • Oceanic trenches
  74. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts • Oceanic trenches • Eg. Marianas Trench
  75. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts • Oceanic trenches • Eg. Marianas Trench • Volcanic islands  Island Arcs
  76. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts • Oceanic trenches • Eg. Marianas Trench • Volcanic islands  Island Arcs • Hawaiian Islands
  77. 2. Destructive Plate Boundaries • Case #2: Oceanic-Oceanic Crusts • Oceanic trenches • Eg. Marianas Trench • Volcanic islands  Island Arcs • Hawaiian Islands • Earthquakes
  78. 2. Destructive Plate Boundaries
  79. 2. Destructive Plate Boundaries
  80. 2. Destructive Plate Boundaries
  81. 2. Destructive Plate Boundaries
  82. 2. Destructive Plate Boundaries
  83. 2. Destructive Plate Boundaries • Case #3: Continental-Continental Crusts
  84. 2. Destructive Plate Boundaries • Case #3: Continental-Continental Crusts • Fold Mountains
  85. 2. Destructive Plate Boundaries • Case #3: Continental-Continental Crusts • Fold Mountains • Eg. Himalayas
  86. 3. Conservative Plate Boundaries Plates slide past each other
  87. 3. Conservative Plate Boundaries
  88. 3. Conservative Plate Boundaries
  89. 3. Conservative Plate Boundaries
  90. 3. Conservative Plate Boundaries • Fault lines
  91. 3. Conservative Plate Boundaries • Fault lines • Eg. St. Andreas Fault, San Francisco
  92. 3. Conservative Plate Boundaries • Fault lines • Eg. St. Andreas Fault, San Francisco • Earthquakes
  93. Dynamic movements of tectonic plates

+ ACS(BR)ACS(BR), 4 months ago

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