Physical Geology - Chapter 17 - The Hydrologic Cycle & Groundwater

1. After oceans, which of the following reservoirs contains the most water?
A) the atmosphere
B) the lakes and rivers
C) the glaciers and polar ice caps
D) the underground waters

C) the glaciers and polar ice caps

2. Which of the following reservoirs contains the least water?
A) the atmosphere
B) the biosphere
C) groundwater
D) lakes and rivers

B) the biosphere

3. The process by which surface water becomes groundwater is called
A) discharge.
B) evaporation.
C) infiltration.
D) transpiration.

C) infiltration.

4. What powers the hydrologic cycle?
A) magnetism
B) mantle convection
C) radioactive decay
D) solar energy

D) solar energy

5. The largest freshwater reservoir in the hydrologic cycle is
A) the atmosphere.
B) groundwater.
C) glaciers.
D) the biosphere.

C) glaciers.

6. The release of water vapor from plants is called
A) evaporation.
B) infiltration.
C) precipitation.
D) transpiration.

D) transpiration.

7. Which of the following terms is a measure of the amount of water vapor in the air as a proportion of the maximum amount the air could hold at the same temperature?
A) dew point
B) evaporation rate
C) relative humidity
D) sublimation point

C) relative humidity

8. Which of the following groundwater contaminations is the most difficult to deal with?
A) chemicals
B) fertilizers
C) septic systems leakage
D) radioactive contaminants

D) radioactive contaminants

9. Which of the following regions has the highest average annual precipitation?
A) northeast United States
B) southwest United States
C) southeast United States
D) central United States

C) southeast United States

10. What is the average annual precipitation in Phoenix, Arizona?
A) fewer than 20 cm
B) 20 to 40 cm
C) 40 to 60 cm
D) more than 60 cm

A) fewer than 20 cm

11. Which of the following regions has the highest annual surface runoff?
A) central Texas
B) southern Florida
C) northern Michigan
D) western Washington

D) western Washington

12. Which of the following rivers carries the most water?
A) the Amazon River in South America
B) the Congo River in Africa
C) the Ganges River in Asia
D) the Mississippi River in North America

A) the Amazon River in South America

13. In the United States, what percentage of the original wetlands has been destroyed?
A) less than 5%
B) approximately 10%
C) approximately 25%
D) more than 50%

D) more than 50%

14. Groundwater represents how much of the world's fresh water?
A) approximately 1%
B) approximately 12%
C) approximately 29%
D) approximately 35%

C) approximately 29%

15. Layers that transmit groundwater are called
A) aquicludes.
B) aquifers.
C) influent streams.
D) unsaturated zones.

B) aquifers.

16. Which of the following unfractured rocks has the highest porosity?
A) granite
B) sandstone
C) schist
D) shale

B) sandstone

17. Which of the following statements regarding porosity and permeability is true?
A) High porosity rocks generally have high permeability.
B) High porosity rocks generally have low permeability.
C) Low porosity rocks generally have high permeability.
D) Porosity and permeability have identical meanings.

A) High porosity rocks generally have high permeability.

18. Which of the following sandstones will have the highest porosity?
A) a poorly sorted, cemented sandstone
B) a poorly sorted, uncemented sandstone
C) a well-sorted, cemented sandstone
D) a well-sorted, uncemented sandstone

D) a well-sorted, uncemented sandstone

19. Permeability is the
A) ability of a solid to allow fluids to pass through.
B) amount of water vapor in the air relative to the maximum amount of water vapor the air can hold.
C) percentage of pore space in a rock.
D) process by which plants release water vapor to the atmosphere.

A) ability of a solid to allow fluids to pass through.

20. In the unsaturated zone, pore spaces in the soil and rock contain
A) air.
B) water.
C) air and water.
D) neither air nor water.

C) air and water.

21. Which of the following combinations make for the best groundwater reservoir?
A) low permeability and low porosity
B) high permeability and low porosity
C) low permeability and high porosity
D) high permeability and high porosity

D) high permeability and high porosity

22. What is the difference between the saturated and unsaturated zones of groundwater?
A) The saturated zone has a higher porosity than the unsaturated zone.
B) The saturated zone has a lower porosity than the unsaturated zone.
C) The pore spaces in the saturated zone are full of water; the pore spaces in the unsaturated zone are not full of water.
D) The pore spaces in the saturated zone are not full of water; the pore spaces in the unsaturated zone are full of water.

C) The pore spaces in the saturated zone are full of water; the pore spaces in the unsaturated zone are not full of water.

23. Which of the following has the highest permeability?
A) gravel
B) sandstone
C) shale
D) silt

A) gravel

24. Which of the following statements about the groundwater table is true?
A) The groundwater table changes when discharge is balanced by recharge.
B) The groundwater table has the same general shape as the topography.
C) The groundwater table is well below the land surface beneath lakes.
D) The groundwater table is elevated near high-volume pumping wells.

B) The groundwater table has the same general shape as the topography.

25. Which of the following statements is true?
A) Influent streams discharge groundwater and are characteristic of arid regions.
B) Influent streams discharge groundwater and are characteristic of humid regions.
C) Influent streams recharge groundwater and are characteristic of arid regions.
D) Influent streams recharge groundwater and are characteristic of humid regions.

C) Influent streams recharge groundwater and are characteristic of arid regions.

26. Which of the following represents the boundary between the saturated zone and the unsaturated zone?
A) aquifer
B) aquiclude
C) groundwater table
D) porosity

C) groundwater table

27. Which of the following statements regarding effluent streams is true?
A) Effluent streams recharge groundwater and are characteristic of humid regions.
B) Effluent streams recharge groundwater and are characteristic of arid regions.
C) Effluent streams are fed by groundwater and are characteristic of humid regions.
D) Effluent streams are fed by groundwater and are characteristic of arid regions.

C) Effluent streams are fed by groundwater and are characteristic of humid regions.

28. What type of aquifer is bounded above and below by relatively impermeable beds?
A) aquiclude
B) confined
C) saturated
D) unconfined

B) confined

29. If the amount of discharge in an aquifer exceeds the amount of recharge, the groundwater table
A) will rise.
B) will drop.
C) will remain the same.
D) may rise or drop depending on the permeability.

B) will drop.

30. Which of the following is not caused by overpumping groundwater?
A) intrusion of salt water into coastal aquifers
B) depletion of an aquifer
C) raising of the land surface
D) development of cracks and fissures at the surface

C) raising of the land surface

31. Which of the following statements about groundwater is true?
A) At the coast, salty groundwater lies on top of fresh groundwater.
B) Groundwater moves from areas where the water table is low to areas where the water table is high.
C) The higher the permeability of an aquifer, the faster the groundwater will flow.
D) The steeper the water-table slope, the slower the groundwater will flow.

C) The higher the permeability of an aquifer, the faster the groundwater will flow.

32. Darcy's law states that the volume of water flowing through a cross-sectional area per time is equal to
A) porosity × hydraulic conductivity.
B) porosity × water table slope.
C) hydraulic conductivity × water table slope.
D) porosity × hydraulic conductivity × water table slope.

C) hydraulic conductivity × water table slope.

33. According to Darcy's law, which of the following aquifers will have the greatest rate of groundwater flow?
A) an aquifer with high hydraulic conductivity and a high hydraulic gradient
B) an aquifer with high hydraulic conductivity and a low hydraulic gradient
C) an aquifer with low hydraulic conductivity and a high hydraulic gradient
D) an aquifer with low hydraulic conductivity and a low hydraulic gradient

A) an aquifer with high hydraulic conductivity and a high hydraulic gradient

34. Which of the following statements about groundwater in coastal regions is true?
A) Fresh water is denser than seawater; therefore, fresh groundwater floats on top of salty groundwater.
B) Fresh water is denser than seawater; therefore, salty groundwater floats on top of fresh groundwater.
C) Seawater is denser than fresh water; therefore, fresh groundwater floats on top of salty groundwater.
D) Seawater is denser than fresh water; therefore, salty groundwater floats on top of fresh groundwater.

C) Seawater is denser than fresh water; therefore, fresh groundwater floats on top of salty groundwater.

35. How fast does most groundwater move in aquifers?
A) a few centimeters per day
B) a few meters per day
C) a few kilometers per day
D) a few tens of kilometers per day

A) a few centimeters per day

36. In what type of rock do most caves form?
A) granite
B) limestone
C) sandstone
D) shale

B) limestone

37. The Ogallala aquifer in the southwestern high plains of Texas and New Mexico consists of
A) basalt and gabbro.
B) sand and gravel.
C) limestone and dolostone.
D) shale and mudstone.

B) sand and gravel.

38. Karst topography forms in regions underlain by
A) basalt.
B) limestone.
C) sandstone.
D) shale.

B) limestone.

39. Stalagmites
A) form in sandstone fractures.
B) form in the pore spaces of a limestone.
C) grow up from the floor of a cave.
D) hang down from the ceiling of a cave.

C) grow up from the floor of a cave.

40. Sinkholes are a possible danger in regions underlain by what type of bedrock?
A) granite
B) limestone
C) sandstone
D) shale

B) limestone

41. Which of the following statements about karst topography is false?
A) Karst topography contains sinkholes.
B) Karst topography forms from freezing and thawing of groundwater.
C) Karst topography does not have a normal river drainage system.
D) Karst topography forms in regions where subsurface limestone is dissolved by groundwater.

B) Karst topography forms from freezing and thawing of groundwater.

42. Which of the following characteristics favors the development of karst topography?
A) high rainfall and fractured limestone bedrock
B) high rainfall and fractured sandstone bedrock
C) low rainfall and fractured limestone bedrock
D) low rainfall and fractured sandstone bedrock

A) high rainfall and fractured limestone bedrock

43. Trichlorethylene (TCE), a serious groundwater contaminant, is used in
A) agriculture.
B) wastewater treatment systems.
C) industrial processes.
D) health and beauty products.

C) industrial processes.

44. Groundwater in agricultural areas may contain high quantities of _______ because of fertilizers.
A) calcium
B) lead
C) nitrate
D) sodium

C) nitrate

49. As one goes deeper in Earth's crust, the porosity __________ and the concentration of dissolved minerals _______.
A) increases; increases
B) increases; decreases
C) decreases; increases
D) decreases; decreases

C) decreases; increases

50. Most of the water coming out of continental hot springs is
A) magmatic water.
B) metamorphic water.
C) meteoric water.
D) seawater.

C) meteoric water.

51. Water that is suitable for drinking is also called ________ water.
A) sanitary
B) fresh
C) potable
D) meteoric

C) potable

52. Crusts of calcium carbonate produced at hot springs are referred to as
A) travertine.
B) hydrothermal deposits.
C) karst.
D) magma.

A) travertine.

53. The world's total water supply is approximately _______ km3.
A) 140 million
B) 1.4 billion
C) 50 billion
D) 2.25 million

B) 1.4 billion

54. Droughts are periods when
A) precipitation is higher than normal.
B) precipitation equals evaporation.
C) precipitation is nonexistent.
D) precipitation is lower than normal.

D) precipitation is lower than normal.

55. ________ is the infiltration of water into the saturated zone, and _______ is the exit of groundwater to the surface.
A) Recharge; discharge
B) Permeation; evaporation
C) Seepage; outflow
D) Hydration; outflux

A) Recharge; discharge

56. The hydraulic gradient is the
A) ratio between the porosity and permeability of an aquifer.
B) ratio between the permeability and elevation difference in an aquifer.
C) ratio between the elevation difference and the flow distance in an aquifer.
D) ratio between the influx and outflow of water in an aquifer.

C) ratio between the elevation difference and the flow distance in an aquifer.

57. The regional aquifer that lies beneath the southwestern United States is called the _____ aquifer.
A) Ogallala
B) Carlsbad
C) Mammoth
D) Long Island

A) Ogallala

58. Groundwater supplies can be contaminated by
A) lead and other heavy metals.
B) nitrates from fertilizers.
C) microorganisms from septic systems.
D) lead and other heavy metals, nitrates from fertilizers, and microorganisms from septic systems.

D) lead and other heavy metals, nitrates from fertilizers, and microorganisms from septic systems.

59. "Hard" water contains an abundance of _________ in solution.
A) calcium
B) bicarbonate
C) magnesium
D) calcium, bicarbonate, and magnesium

D) calcium, bicarbonate, and magnesium

60. Groundwater that tends to be "hard" has usually passed through
A) sandstone.
B) limestone.
C) granite.
D) basalt.

B) limestone.

61. Potable water is a term that covers all
A) groundwater.
B) drinkable water.
C) hydrothermal water.
D) seawater.

B) drinkable water.

62. The recycling of water on Earth is known as the ________ cycle.
A) water
B) wet
C) hydrous
D) hydrologic

D) hydrologic

63. The transformation of solid ice directly into water vapor is called
A) evaporation.
B) melting.
C) sublimation.
D) transpiration.

C) sublimation.

64. A human being can survive off as little as ___ liters of water per day.
A) 0.2
B) 2
C) 20
D) 200

B) 2

65. The per capita daily use of water in the United States is approximately _______ liters.
A) 0.6
B) 6
C) 600
D) 6000

D) 6000

66. Wetlands are valuable because they
A) store little water.
B) are great for land development.
C) can be drained easily.
D) help control flooding.

D) help control flooding.

67. Vuggy porosity would most likely be found in a
A) gneiss.
B) granite.
C) shale.
D) limestone.

D) limestone.

68. The mathematical equation that describes the flow of water underground is known as _______ law.
A) Murphy's
B) Darcy's
C) Henry's
D) Newton's

B) Darcy's

69. How has Darcy's law been verified in nature?
A) by dropping dye into groundwater wells
B) by measuring the rate of underground rivers in caves
C) by measuring the flow rate of springs
D) by measuring the rate at which the water table falls or rises

A) by dropping dye into groundwater wells

70. What startling discovery did scientists make when studying deep underground aquifers?
A) They found hydrothermal waters with unusual chemistry.
B) They found ancient microorganisms.
C) They found unusual cave formations.
D) They found ore deposits.

B) They found ancient microorganisms.

71. The main difference between a hot spring and a geyser lies in the
A) temperature of the water.
B) chemistry of the water.
C) bedrock the water flows through.
D) regularity of the underground plumbing system.

D) regularity of the underground plumbing system.

72. Geysers have ____________ than regular hot springs.
A) hotter water
B) colder water
C) more irregular plumbing systems
D) a higher recharge rate

C) more irregular plumbing systems

73. Sublimation is a process whereby water is returned to the hydrologic cycle from
A) lakes.
B) the ocean.
C) glaciers.
D) groundwater.

C) glaciers.

74. Given the dew point (%) and temperature, which of the following air masses will hold the most water overall? Assume that the air masses all started out dry and have the same volume.
A) 50% at 5˚C
B) 50% at 15˚C
C) 60% at 5˚C
D) 60% at 15˚C

D) 60% at 15˚C

75. Roughly what percentage of the world's runoff is carried by the Amazon River?
A) 5%
B) 25%
C) 50%
D) 75%

B) 25%

76. California and Ohio both
A) belong to the Mississippi River drainage system.
B) have 10% of their original wetlands left.
C) have high precipitation.
D) have access to large freshwater lakes.

B) have 10% of their original wetlands left.

77. Swamps are important in hydrologic system because they
A) serve as collection sites for organic matter that eventually turns into coal, oil, and gas.
B) help regulate the flooding of rivers.
C) can be drained to create new farmland.
D) are wetlands.

B) help regulate the flooding of rivers.

78. Swamps are important components of hydrologic system because they
A) turn organic matter into peat.
B) help alleviate droughts.
C) are great farmlands once drained.
D) are wetlands.

B) help alleviate droughts.

79. What type of porosity would you expect to be most common in granite?
A) fracture
B) intergranular
C) vuggy
D) they are all similarly common

A) fracture

80. What type of porosity would you expect to be most common in limestone?
A) fracture
B) intergranular
C) vuggy
D) they are all similarly common

C) vuggy

81. What type of porosity would you expect to be most common in sandstone?
A) fracture
B) intergranular
C) vuggy
D) they are all similarly common

B) intergranular

82. Layers that are impervious to groundwater flow are called
A) aquicludes.
B) aquifers.
C) influent streams.
D) unsaturated zones.

A) aquicludes.

83. Since 1965, most groundwater has been withdrawn for
A) irrigation.
B) public supply.
C) rural water supply.
D) thermoelectric power.

A) irrigation.

84. Between 1960 and 1965, ______ groundwater went to irrigation and _____ groundwater for thermoelectric power.
A) less; less
B) more; more
C) less; more
D) more; less

D) more; less

85. How old is the oldest water discovered on Earth?
A) 1,500 years
B) 1.5 million years
C) 250 million years
D) 1.5 billion years

D) 1.5 billion years

86. Where was the oldest water on Earth found?
A) in a deep mine
B) in a deep drill hole
C) trapped inside ancient salt deposits
D) in the Ogallala Aquifer

A) in a deep mine

87. How many states are underlain by the Ogallala Aquifer?
A) two
B) four
C) eight
D) 10

C) eight

88. Icicles are to ice what ________ are to limestone.
A) stalagmites
B) stalactites
C) carbonates
D) marbles

B) stalactites

89. Karst topography is common in which of the following states?
A) Alabama, California, New Mexico
B) Florida, Indiana, Kentucky
C) Michigan, Iowa, Illinois
D) New York, Washington, Texas

B) Florida, Indiana, Kentucky

90. What is the most common source of groundwater pollution?
A) chemical spills
B) fertilizer overuse
C) septic systems leakage
D) radioactive waste disposal

C) septic systems leakage