Geo Test

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Geo Test
2013-05-01 01:18:13

Geo final exam practice
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  1. What type of volcano is Augustine?
  2. Augustine Volcano can produce this type of hazard when it collapses during large eruptions?
  3. how long would it take for a tsunami coming from Augustine volcano to reach Homer, Alaska?
    90 minutes
  4. Magma is made at subduction zones by?
    Wet partial melting
  5. Decompression melting occurs at which two tectonic areas?
    Hot spots, Mid ocean ridges
  6. Shield volcanoes are common in which of the following plate tectonic setting?
    Hot spots
  7. What type of partial melting happens at subduction zones?
    Wet Partial melting
  8. Name the three plate tectonic regions on earth that produce volcanoes?
    Hot Spots, Spreading centers, Subduction zones
  9. Briefly describe decompression melting?
    rising mantle rocks expand and as they move to lower pressures they can melt.
  10. Briefly describe wet partial melting?
    adding water to hot mantle rocks at subduction zones.
  11. Volcanic earthquakes that show p and s waves are called?
    Volcano-tectonic (vt)
  12. How are VT earthquakes beneath a volcano located?
  13. What is one way we monitor volcanoes?
  14. This type of seismic signal happens when magma rise to the surface causing the volcano to resonate with a continuous vibration:
    Harmonic tremor
  15. _______Volcano is exhibiting signs of unrest above its known background level?
  16. ________A hazardous eruption is imminent, underway, or suspected.
  17. Green-normal
    non-eruptive state.
  18. Yellow-
    Volcano shows signs of unrest above known baseline levels.
  19. Orange-
    Heightened unrest, with increased likelihood of eruption.
  20. Red-Eruption
    forecast to be imminent with significant ejection of ash, or eruption is underway and producing significant ash.
  21. Normal-
    Typical background activity. No real threat to those in vicinity.
  22. Advisory-
    Elevated unrest. Closely monitored volcano.
  23. Watch-
    Either limited hazards posed by an ongoing but small eruption, or escalating activity signifies increased potential for an eruption to occur.
  24. Warning-
    Highly hazardous eruption imminent or underway.
  25. Volcanoes that have erupted within the past 10,000 years, and usually erupt frequently are considered?
  26. Volcanoes that have been active within the past 10,000 years, but not recently. They may erupt again, but have not erupted in a long while.
  27. Volcanoes that have not erupted within the past 10,000 years and are not expected to ever erupt again. It is approximately 10 million years old.
  28. volcanoes that have not erupted in a long time, and then suddenly surprise everyone by coming back to life.
  29. Volcanoes that explode forcefully. They eject rock fragments out of the vent at high speeds. What type of hazard is this?
    Ash fall/Ash clouds
  30. Deadly, hot (200-700 celsius) avalanches of gas, rock fragments, fine powdery ash rushing down the slopes of volcanoes. What type of hazard is this?
    Pyroclastic flows
  31. Fast moving torrents of muddy, sandy, debris-laden water originating on the flanks of a volcano. What type of hazard is this?
  32. Volcanic eruptions that dump large volumes of pyroclastic flows or landslides into water can cause?
  33. What type of hazard has a typical speed of 1 to 10 km/hour, Usually slow enough that people can leave?
    Basalt lava flow
  34. All areas downwind from the volcano are at risk from what type of hazard?
    Ash clouds and Ash fall
  35. ______ are natural (or human caused) processes that have the potential to wreak havoc, whether humans are threatened or not.
  36. ______describes the effects that those hazards may pose for people, property, crops, livestock or other infrastructure in a threatened area?
  37. How many people fly above Alaskan volcanoes each day?
  38. Tacoma, Washington is at risk from which of the following hazards producted by Mt. Rainier?
  39. Mt. Redoubt caused damage to a KLM 747 jet aircraft. how much did this near-disaster cost?
    $80 million
  40. Lahars impacted which of the following alaskan locations during the 2009 eruption of Mt Redoubt, Alaska?
    Drift River oil terminal
  41. How many people are at risk from pyroclastic flows from Vesuvious volcano, in Italy?
    >1 million
  42. What % SiO2 is in Basalt?
  43. What % SiO2 is in Andesite?
  44. What % SiO2 is in Dacite?
  45. What % SiO2 is in Rhyolite?
  46. What is the size range for Ash?
    <2 mm
  47. What is the size range for Lapilli?
    2-64 mm
  48. What is the size range for blocks and bombs?
    >64 mm
  49. Forms during collapse of the volcano into itself?
  50. Smallest volcano. Made of all granular pyroclasts?
    Cinder Cone
  51. Volcanoes that form underneath glaciers?
  52. Largest volcano by volume. Made of stacks of runny lava flows?
    Shield volcano
  53. Steepest slope angle. Forms a perfect, tall, conical volcano shape?
  54. Lava erups from a long crack in the ground. Common along mid ocean ridges?
  55. Shield volcanoes have a very low slope angle because they are made of?
    Runny lava flows
  56. Volcanic rocks that are full of holes that represent trapped gas bubbles from foamy magna have which type of texture?
  57. Inneous rocks that form as magma completely cools inside the earths crust and never erupts are called?
  58. What does the VEI Scale represent?
    Volcano Explosivity Index
  59. How often do large, VEI 8 eruptions typically happen on earth?
    1-2 million years
  60. What gas can signify that a volcano might erupt soon?
  61. Hawaiin style eruptions are _____ fountains, have ____Viscosity, ____SiO2 basalt magma and _____ exlosiveness?
    Lava, Low, Low, Low
  62. Strombolian eruptions are _____/Lapilli clouds, _____explosiveness, ______SiO2, _______Viscosity?
    Ash, Moderate, Low, Low
  63. Vulcanian eruptions are _____clouds, _____-_____ viscosity magma, _______-_______ SiO2, ______-_____ explosiveness?
    Ash, medium to high, medium to high, moderate to high
  64. Plinian style eruptions are _____Viscosity, _____gas content, _____ SiO2, ________ explosiveness
    high, high, high, highly
  65. Hawaiin erupts what type of magma?
  66. Strombolian erupts what type of magma?
  67. Vulcanian erupts what type of magma?
  68. Plinian erupts what type of magma?
  69. What is the difference between A'a and Pahoe'hoe lava flows?
    A'a is slightly higher in viscosity, and flows slightly faster than pahoe'hoe, A'a is breaks itself up and rolls along the ground like a tank tread
  70. Glassy rocks erupt ______causing no time for crystals to form?
  71. Crystalline rocks ______ erupted and is composed of all _______?
    Never, crystals
  72. Vesiculare rocks contains lots of trapped ____ bubbles?
  73. Porphyritic contains large _______ floating among much smaller ______ and _______?
    Crystals, glass
  74. Glassy rocks are intrusive or extrusive?
  75. Crystalline rocks are intrusive or extrusive?
  76. Vesicular rocks are intrusive or extrusive?
    extrusive pumice
  77. porphyritic rocks are intrusive or extrusive?
  78. Glass and trapped bubbles contained in volcanic rocks signifies that they are?
  79. _______rocks are those that form from magma completely solidifying underneath the ground, that never erupted?
  80. Glassy rocks have few if any _____?
  81. Crystalline contains no ______?
  82. Vesicular rocks are full of ______?
  83. Porphyritic rocks have large _______, surrounded by ______?
    crystals, glass
  84. Which volcanic rock textures represents magma that has cooled very slowly in the crust of the earth, and never erupted?
  85. Magma that does not fragment, that flows out of the volcano in large masses are _______ eruptions?
  86. Fragmentation of magma results in pulverization to tiny bits of ash are _________ eruptions?
  87. Effusive eruptions happen because the conduit is ______ and _______, allowing gas overpressures to be relieved?
    Fractured and leaky
  88. ________ eruptions create huge gas over-pressures and allow the magma to fragment itself violently, creating lots of ash?
  89. A block or bomb is a _______?
  90. What controls or causes the shape of a stratovolcano?
    Layers of lava and ash/tephra grains
  91. What is the most common type of volcano that occurs at mid ocean ridges?
  92. Alaska's subductions zone most commonly creates which of the following types of volcanoes?
  93. Dry, degassed lava flows result from which type of eruption?
  94. what is a common mineral found in most magmas?
  95. How are VT earthquakes beneath a volcano located?
  96. what are the two volcanic gases that are most important to monitor because they indicate magma is rising up and the volcano is likely to erupt soon?
    CO2, SO2
  97. Which is the largest type of volcano on Earth, by volume?
    a. Cinder cone b. Stratovolcano c. Shield volcano d. None of these
  98. The maximum angle to the horizontal at which rocks, soil, etc (granular materials) can form a conical pile is called the:
    a. Collapse angle b. Friction c. Angle of repose d. Horizontal angle
  99. Which of the following is the most hazardous type of volcano in terms of impacts to people? 60% of all volcanoes on Earth are this type:
    a. Cinder cones b. Fissures c. Stratovolcanoes d. None of these