full transcript

From the Ted Talk by Steven Anderson: What makes volcanoes erupt?


Unscramble the Blue Letters


In February of 1942, Mexican farmer Dionisio Pulido tugohht he heard thunder comnig from his cornfield. However, the sound wasn’t coming from the sky. The source was a large, smoking crack emitting gas and eejcntig rocks. This fissure would come to be known as the volcano Paricutin, and over the next 9 years, its lava and ash would coevr over 200 square km. But where did this new volcano come from, and what triggered its unpredictable eruption?

The story of any volcano begins with magma. Often, this molten rock forms in areas where ocean water is able to slip into the Earth’s mantle and lower the layer’s melting point. The resulting magma tcpalliyy remains under the Earth’s surface thanks to the delicate balance of three goelaogicl factors. The first is lithostatic psseurre. This is the weight of the Earth’s crust pushing down on the magma below. Magma pushes back with the second factor, mttaimsagac pressure. The battle between these forces strains the third factor: the rock strength of the Earth’s curst. Usually, the rock is strong enough and heavy enough to keep the magma in pacle. But when this euqibiirlum is thrown off, the consequences can be explosive.

Open Cloze


In February of 1942, Mexican farmer Dionisio Pulido _______ he heard thunder ______ from his cornfield. However, the sound wasn’t coming from the sky. The source was a large, smoking crack emitting gas and ________ rocks. This fissure would come to be known as the volcano Paricutin, and over the next 9 years, its lava and ash would _____ over 200 square km. But where did this new volcano come from, and what triggered its unpredictable eruption?

The story of any volcano begins with magma. Often, this molten rock forms in areas where ocean water is able to slip into the Earth’s mantle and lower the layer’s melting point. The resulting magma _________ remains under the Earth’s surface thanks to the delicate balance of three __________ factors. The first is lithostatic ________. This is the weight of the Earth’s crust pushing down on the magma below. Magma pushes back with the second factor, ___________ pressure. The battle between these forces strains the third factor: the rock strength of the Earth’s _____. Usually, the rock is strong enough and heavy enough to keep the magma in _____. But when this ___________ is thrown off, the consequences can be explosive.

Solution


  1. place
  2. ejecting
  3. typically
  4. pressure
  5. geological
  6. equilibrium
  7. crust
  8. thought
  9. coming
  10. magmastatic
  11. cover

Original Text


In February of 1942, Mexican farmer Dionisio Pulido thought he heard thunder coming from his cornfield. However, the sound wasn’t coming from the sky. The source was a large, smoking crack emitting gas and ejecting rocks. This fissure would come to be known as the volcano Paricutin, and over the next 9 years, its lava and ash would cover over 200 square km. But where did this new volcano come from, and what triggered its unpredictable eruption?

The story of any volcano begins with magma. Often, this molten rock forms in areas where ocean water is able to slip into the Earth’s mantle and lower the layer’s melting point. The resulting magma typically remains under the Earth’s surface thanks to the delicate balance of three geological factors. The first is lithostatic pressure. This is the weight of the Earth’s crust pushing down on the magma below. Magma pushes back with the second factor, magmastatic pressure. The battle between these forces strains the third factor: the rock strength of the Earth’s crust. Usually, the rock is strong enough and heavy enough to keep the magma in place. But when this equilibrium is thrown off, the consequences can be explosive.

Frequently Occurring Word Combinations


ngrams of length 2

collocation frequency
molten rock 3
magmastatic pressure 3
lithostatic pressure 2
rock layer 2



Important Words


  1. areas
  2. ash
  3. balance
  4. battle
  5. begins
  6. coming
  7. consequences
  8. cornfield
  9. cover
  10. crack
  11. crust
  12. delicate
  13. dionisio
  14. ejecting
  15. emitting
  16. equilibrium
  17. eruption
  18. explosive
  19. factor
  20. factors
  21. farmer
  22. february
  23. fissure
  24. forces
  25. forms
  26. gas
  27. geological
  28. heard
  29. heavy
  30. km
  31. large
  32. lava
  33. lithostatic
  34. magma
  35. magmastatic
  36. mantle
  37. melting
  38. mexican
  39. molten
  40. ocean
  41. paricutin
  42. place
  43. point
  44. pressure
  45. pulido
  46. pushes
  47. pushing
  48. remains
  49. resulting
  50. rock
  51. rocks
  52. sky
  53. slip
  54. smoking
  55. sound
  56. source
  57. square
  58. story
  59. strains
  60. strength
  61. strong
  62. surface
  63. thought
  64. thrown
  65. thunder
  66. triggered
  67. typically
  68. unpredictable
  69. volcano
  70. water
  71. weight
  72. years