geol final

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geol final
2015-12-09 20:56:38

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  1. In what physical state do changes in a rock occur to make a metamorphic rock?
    The solid state
  2. What is the general term for the rock before it is metamorphosed?
    A protolith
  3. What are potential sources of heat that can cause metamorphism?
    • Deep in the Earth’s crust
    • Close to an intrusive body
  4. At what temperature does metamorphism usually begin?
  5. What is confining pressure?
    Pressure that is equal in all directions
  6. In what direction do micas crystalize in a rock that has foliation?
    • Perpendicular to the direction of maximum compression
    • Parallel to the direction of shearing
  7. What tectonic environment do blueschists form in?
    A subduction zone
  8. What is the protolith of marble?
  9. What is the protolith of quartzite?
    Quartz Sandstone
  10. What is the state rock of California?
  11. What happens to the carbon content of coal as it experiences higher grade metamorphism?
    Carbon content increases
  12. What is the protolith of slate?
  13. How large are the mica crystals in a phyllite?
    Larger than in slate but still microscopic
  14. How large are the mica crystals in a schist?
  15. What is the appearance of a gneiss?
    Alternating dark and light bands
  16. What is the principle that says layers of sediment deposited in water form horizontal (or near horizontal) beds?
    The principle of original horizontality
  17. How can tilting of sedimentary layers occur?
    During mountain building
  18. How can folding of sedimentary layers occur?
    In compressional environments
  19. What is the position of the oldest layer in a stratigraphic sequence?
    The bottom
  20. What type of underlying unconformity involves igneous or metamorphic rock?
    A nonconformity
  21. In what era do fossils of complex life forms begin appearing?
    The Paleozoic
  22. In what era did dinosaurs roam the earth?
    The Mesozoic
  23. What do we think lead to the extinction of the dinosaurs?
    • Asteroid or comet impact
    • Flood basalts happening in India
  24. What is the name of the current era in geologic history?
    The Cenozoic
  25. What technique do we use to come up with absolute ages of rocks?
    Radiometric dating
  26. How many years back can we date something with 14C decay?
    40,000 years
  27. If we start of with 64,000 atoms of some radioactive isotope, how many radioactive atoms do we have left after three half lives?
    8,000 radioactive atoms
  28. Approximately how old is the Earth?
    4.5 billion years
  29. list from youngest to oldest
    • Youngest
    • J
    • E
    • G
    • K
    • D
    • tilting & erosion
    • A
    • F
    • C
    • I
    • B
    • H
    • Oldest
  30. Where is most of the water in the hydrosphere located?
    The Oceans
  31. Which is more porous: a sandstone or uncemented sand?
    Uncemented Sand
  32. How much water is found in the saturated zone?
    All the pore spaces are filled with water
  33. How much water is found in the unsaturated zone?
    Some to none of the pore spaces are filled with water
  34. At what speeds does water usually flow through the subsurface?
    Centimeters to meters per day
  35. What factors does flow velocity in the subsurface depend on?
    • Slope Angle
    • Permeability of the rock
  36. Would a unfractured granite be considered a potential aquifer of aquitard?
  37. Would a conglomerate be considered a potential aquifer or aquitard?
  38. What feature is formed in the water table when a well is regularly used?
    A cone of depression
  39. What is the name of the well where water is under pressure and rises above the water table?
    An artesian well
  40. What surface features form when the water table intersects the surface?
    • A lake
    • A stream/river
    • A spring
  41. What contaminants are not purified by the soil?
    • Pesticides
    • Toxic Chemicals
  42. What can occur when wells near the seashore pump too much water?
    Saltwater intrusion
  43. What is the name of the features in caves that grow up from the cave floor?
  44. How is water heated to form hot springs and/or geysers?
    • Ground water comes close to an magma body
    • Ground water circulates and reaches unusual depths in the crust
  45. What is the top of the sautrated zone in the ground called?
    water table
  46. What type of stream has a higher discharge upstream?
    A losing stream
  47. What is the name given to a rock before it undergoes metamorphism?
  48. What is a polymorph?
    Minerals with the same composition but different crystal forms
  49. What type of dating puts objects/events in order from oldest to youngest?
  50. What do we think caused the mass extinction at the end of the Mesozoic?
    An asteroid impact and/or flood basalts in India
  51. What technique do we use to come up with an absolute age of a rock?
    Radiometric analysis
  52. What protects us from the solar wind?
    Earth's magnetic field
  53. What are the gas giant planets mostly made of?