GCSE Geography

  1. draw a diagram of a volcano
    Image Upload 1
  2. shield volcano
    Image Upload 2
  3. composite volcano
    Image Upload 3
  4. super-volcano eruptions can equal the force of ...... Hiroshima bombs exploding every second
  5. the worlds last super-volcano eruption occurred in
    Indonesia 74,000 years ago
  6. give an example of a supervolcano
    Yellowstone National Park , NW USA , is an example of a super-volcano
  7. super-volcano eruptions are large enough to
    affect almost everybody on Planet Earth for example airports all over the world would likely have to shut down as planes and runways would probably get covered in volcanic ash
  8. a super-volcano is
    a volcano that erupts with a massive volume of material 100km3 of magma
  9. compared to a regular volcano this is huge as Mt St Helens , USA erupted
    less than 1km3 when it violently erupted in 1980
  10. differences between SV's and Volcanoes
    • 1) power/size of eruption 
    • 2) shape 
    • 3) location
  11. magnitude - SV's are more ... than regular volcanoes , erupting lots more .... , .... & .... . The eruptions are less ..... but when they do erupt , are much more .... & .... ..... . They can have an impact on our entire planet
    • powerful 
    • magma , ash & gas 
    • frequent 
    • dangerous & last longer
  12. shape - unlike regular volcanoes SV's do NOT have a distinct ..... shape . They cover such a ..... .... with so many .... & ..... that it is impossible to see them without a satellite . in fact SV's main feature is a huge ...... ..... filled with ......
    • cone 
    • wide area 
    • peaks & vents 
    • underground chamber
    • magma
  13. location - unlike regular volcanoes SV's are NOT distributed in ..../.... on ..... ..... ..... . SV's are ..... i.e. on ..... .... as they are located above ..... ....
    • strips/clusters
    • tectonic plate boundaries 
    • isolated 
    • their own 
  14. explain how a super-volcano forms at a hotspot using a diagram
    • 1) magma rises up through cracks in the crust to form a large magma basin below the surface . the pressure of the magma causes a circular bulge on the surface several km wide 
    • 2) the bulge eventually cracks , creating vents for lava to escape through . The lava erupts out of the vents causing earthquakes and sending up gigantic plumes of ash and rock 
    • 3) as the magma basin empties , the bulge is no longer supported so it collapses - spewing up more lava 
    • 4) when the eruption is finished there's a big crater (called a caldera) left where the bulge collapsed . sometimes these get filled with water to form a large lake , e.g. lake Toba in Indonesia  
    • Image Upload 4
  15. list some global consequences of a super volcano
    1) ash will shoot kilometres into the air and block out almost all daylight over whole continents . this will cause global temperatures to decrease by 5-15 degrees centigrade this can trigger mini ice ages as less heat energy from the sun gets to earth a large percentage of the world's plant life would be killed by the ash and drop in temperature. Also, virtually the entire of the grain harvest of the Great Plains would disappear in hours, as it would be coated in ash. Similar effects around the world would cause massive food shortages which will cause many deaths and humans may become extinct .
  16. explain where fold mountains are formed
    • when tectonic plates collide the sedimentary rocks that have been built up between them are folded and forced upwards to form mountains 
    • so fold mountains are formed at destructive plate margins and places where there used to be destructive margins e.g. the west coast of America 
    • You can get fold mountains where a continental plate and oceanic plate collide e.g. the Andes in South America 
    • you can also get fold mountains where two continental plates collide e.g. the Himalayas in Asia
  17. explain the formation of fold mountains
    • rivers deposited huge quantities of sediments in depressions called geosynclines
    • over millions of years the sediments were compressed into sedimentary rock such as sandstone and limestone 
    • the plates moved together at a destructive plate margin forcing the sedimentary rock upwards into a series of folds
  18. deposition
    material that has been dropped somewehere
  19. geosyncline
    ocean/sea basin
  20. sedimentary rock
    a rock made of layers of smaller particles
  21. compressional plate boundary
    = destructive plate boundary - a tectonic plate boundary where the tectonic plates move together
  22. fold mountain areas have lots of
    very high mountains , which are very rocky with steep slopes . There is often snow and glaciers  in the highest parts and lakes and valleys between the mountains . The vegetation is often sparse
  23. fold mountains are
    huge uplifted sections of sedimentary rock originally formed on ancient ocean floor areas called geosynclines, so fold mountains often have fossilised remains of ancient sea creatures in them . fold mountains occur in long strips or belts , known as ranges . the ranges often have volcanoes piercing through them
  24. earth's recent mountain building phases (in the last 50 million years or so) have created
    "young fold mountains" which are still rising by about 4cm per year
  25. examples of young fold mountains are the :
    • Alps 
    • Rockies 
    • Himalayas 
    • Andes
    • Pyrenees
    • Caucasus
  26. what is the highest mountain in the world
    Mt Everest 8848m which is part of the Himalayas fold mountain range
  27. land use in fold mountains areas is difficult because of
    the steep relief , difficult climate , limited transport and infrastructure and also there is a lack of potential markets
  28. but the five main types of land use that do exist are
    • farming 
    • HEP 
    • mining 
    • forestry 
    • tourism
  29. when were the Alps formed
    30-40 million years ago
  30. where are the alps
    they are the border between France , Italy , Switzerland and Germany
  31. the highest peak of the alp is
    Mount Blanc in France it is 4810m
  32. the alps is the source of Europe's major rivers
    the Rhine and the Rhone
  33. the alps have lots of glacial landforms
    • a pyramidal peak : The Matterhorn in Switzerland 
    • a U shaped glacial valley : Rhone Valley 
    • ribbon lakes : Lakes Como and Garda 
    • the Alps also have many corries and arretes
  34. a major problem for people created by fold mountains is
    accessibility meaning that transport and communication is difficult
  35. there are accessibility problems because
    the mountains are very steep and high and there is virtually no flat land
  36. a good example of difficult communication in the Alps is
    the steep , twisting and winding road called ST Gotthard Pass , in the Alps between Switzerland and Italy . Travel on this road is frequently disrupted by rock falls , avalanches and bad weather
  37. the St Gotthard Road Tunnel a (tunnel through the Alps) was opened in
    1980 as a better alternative to the Gotthard Pass
  38. The Gotthard Road Tunnel over ..... miles long is the .... longest road tunnel in the world and the longest in the Alps . It cost .... and took .... to build
    • 10
    • third 
    • millions 
    • ages
  39. what are the advantages of the tunnel
    it is quicker than the old pass as it is straighter and does not get affected by snow or ice or avalanches or rock falls
  40. what are the disadvantages of the tunnel
    although it is generally safer than the twisty mountain roads disasters can sometimes happen e.g. the Mount Blanc tunnel fire of 1999 . This killed 39 people and the tunnel had to close for 3 years while investigations and safety checks and updates were carried out
  41. plans have now been made to
    add to The Gotthard Road Tunnel with a new rail tunnel called St Gotthard Base Tunnel
  42. St Gotthard Base Tunnel will be
    the longest railway tunnel in the world linking Switzerland with Italy
  43. it will take .... years of planning and .... years of construction
    • 10
    • 15
  44. it was started in
  45. it will be finished in
  46. it will be ....km long
  47. it will take ....million passengers a year
  48. it will take ....million tons of cargo a year
  49. its aim is
    to reduce traffic in the road tunnel which has increased 12 fold in 25 years
  50. it will cost £..... million
Card Set
GCSE Geography