Continental Drift theory

• Who created the theory of continental drift and the supercontinent Pangaea?

  Alfred Wegener
• What evidence supports the theory of continental drift using coastlines?

  • Coastlines fit together like a jigsaw
  • Example: South America and Africa
  • Coastlines change due to erosion
  • Continental shelf shows less erosion
• How do glacial deposits support the theory of continental drift?

  • Glaciers cannot form over oceans
  • Striations found near equators
  • Similar striations in Australia, South America, India
  • Suggests these continents were once connected
• What geological evidence supports continental drift?

  • Matching rock sequences in Africa and South America
  • Thick coal deposits found in different continents
  • Mountain ranges in USA, Scotland, Norway suggest connection
  • Coal deposits in Antarctica indicate tropical plants
• What fossil evidence supports the theory of continental drift?

  • Glossopteris fauna found in diverse environments
  • Freshwater reptiles like Mosasaurs found near seawater
  • Glossopteris seeds too large to be wind-carried
• What is palaeomagnetism?

  Fossilized magnetism
• How does palaeomagnetism support continental drift?

  • Iron fillings align with magnetic north in cooling rocks
  • Earth's polarity changes affect rock orientation
  • Ocean bed strips show magnetic orientation corresponds to time scale
  • Sea floor spreading moves material like a conveyor belt
• Where is the deepest part of the ocean located?

  By the continental shelf
• Where are the youngest rocks found?

  Along the mountain chain
• What moves the continents apart?

  The tectonic plates
• What are trenches defined as?

  Old crust consumed (deepest ocean)
• What are ridges defined as?

  New crust that forms (shallow ocean)
• What is seafloor spreading?

  A geological process where tectonic plates split apart
• Who created the theory of continental drift and the supercontinent Pangaea?

  Alfred Wegener
• What evidence supports the theory of continental drift using coastlines?

  • Coastlines fit together like a jigsaw
  • Example: South America and Africa
  • Coastlines change due to erosion
  • Continental shelf shows less erosion
• How do glacial deposits support the theory of continental drift?

  • Glaciers cannot form over oceans
  • Striations found near equators
  • Similar striation orientation in Australia, South America, India
  • Suggests these continents were once connected
• What geological evidence supports the theory of continental drift?

  • Matching rock sequences in Africa and South America
  • Thick coal deposits found in different continents
  • Mountain ranges in the USA, Scotland, Norway suggest connection
  • Coal deposits in Antarctica indicate tropical conditions
• What fossil evidence supports the theory of continental drift?

  • Glossopteris fauna found in diverse environments
  • Freshwater reptiles like Mosasaurs found in seawater
  • Glossopteris seeds too large for wind transport
• What is palaeomagnetism?

  Fossilized magnetism
• How does palaeomagnetism support the theory of continental drift?

  • Iron fillings align with magnetic north in cooling rocks
  • Earth's polarity changes affect rock orientation
  • Ocean bed strips show magnetic orientation corresponding to time scale
  • Indicates sea floor spreading and movement of continents
• Where is the deepest part of the ocean located?

  By the continental shelf
• Where are the youngest rocks found?

  Along the mountain chain
• What moves the continents apart?

  The tectonic plates
• What are trenches defined as?

  Old crust consumed (deepest ocean)
• What are ridges defined as?

  New crust that forms (shallow ocean)
• What is seafloor spreading?

  A geological process where tectonic plates split apart