1. Explain the term "Constructive Plate Boundary."
    When the two plates move apart and magma erupts to fill in the gap which creates new land or islands.
  2. Explain the term "Destructive Plate Boundary."
    When the two plates collide, causing the oceanic plate to be pushed down into the mantle to be destroyed/ melted. This can cause earthquakes or volcanic eruptions.
  3. Explain the term "Conservative Plate Boundary."
    When the two plates slide past each other and can trigger earthquakes due to friction.
  4. Name the 6 different plates.
    • Australasian
    • Urasian
    • North American
    • South American
    • Antarctic
    • African
  5. Describe the Continental plate.
    Thicker but less dense than oceanic plates.
  6. Describe the oceanic plate.
    Thinner but denser than the continental plate.
  7. What is subduction?

    C) The sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate.
  8. What are the effects of subduction?
    • Fold mountains to form
    • Earthquakes
    • Volcanic eruptions
  9. What is sea-floor spreading?
    The process of which tectonic plates break away from each other under water which causes the seas/ oceans to gradually become larger.
  10. What are Fold Mountains?
    These are mountains that are formed mainly by the effects of folding on layers within the upper part of the Earth's crust.
  11. How do Fold Mountains occur?
    They are caused along the lines of both destructive and conservative plate boundaries. They from when two plates with landmasses on them move towards each other. The plates then push layers of accumulated sediment in the sea .into folds between them.
  12. How do tectonic plates move?
  13. What is convection?
    When plates move due to, in the mantle, the movement of which the hot magma rises to the top and the cooler semi-molten magma falls to the bottom to heat up again.
  14. What is magnitude?
    A number which represents the danger level/ force of an Earthquake or a volcanic eruption.
  15. What are fault lines?
    Where 2 plates meet.
  16. How are fault lines connected to volcanoes and earthquakes?
    This is because fault lines are the place of which plates either break away, collide or slide past one another (these are different plate boundaries which trigger earthquakes or volcanic eruptions).
  17. Where are most of the world's active volcanoes found?
    They have formed a ring around the pacific ocean called the Ring of Fire.
  18. How many strata volcanoes are found in the Ring of Fire?
  19. Name 2 types of volcano.
    • Strato
    • Shield
  20. Describe a strato volcano.
    • Tall
    • Explosive
    • Conical shaped (slopes above 10 degrees)
  21. Describe a shield volcano.
    • Have gentle slopes
    • Have runny lava that almost pours out
  22. Why do people live in volcanic zones?
    • Geothermal energy can be made and is better for the environment
    • Tourism
    • The soil is richer and more fertile
  23. Describe the Mantle.
    • Widest part of the Earth with a thickness of 2,900km.
    • Made of semi-molten rock called magma.
  24. Describe the Crust.
    • Made of solid rock
    • 0-60km thick
  25. Describe the outer core.
    • Liquid
    • Made of nickel and iron
    • Can reach a temperature of 5,500 degrees C
  26. Describe the inner core.
    Hottest part of the earth at 5,500 degrees C.
  27. Indian Ocean Tsunami/ Earthquake
    • 2004
    • Magnitude 6.9
    • San Francisco
    • October 18/19
    • 63 dead
    • 3000 injured
    • 13 000 homeless
    • $7 billion of damage
  28. Mount Saint Helens Eruption
    • 1980
    • 57 deaths
    • $2.8 billion of damage
    • Washington State
    • 18 may
  29. Nimitz Highway Quake
    • 1989
    • October 18
    • 7 deaths but 250 cars were still trapped
    • $7 Billion of damage
Card Set
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