Deck 17: Groundwater

Question 1

What force pushes groundwater from pore space to pore space when below the water table?

A)Gravity
B)Hydraulic gradient
C)Hydraulic conductivity
D)Artesian pressure

Answer 1

B

Question 2

What percentage of Earth's liquid freshwater is in the form of groundwater?

A)97.2%
B)96%
C)0)62%
D)0)03%

Answer 2

B

Question 3

What is permeability?

A)Volume of pore space in a material
B)Ability to transmit water
C)When ice crystals deform and slide past each other
D)Dissolution of carbonate rock due to acid

Answer 3

B

Question 4

Which of the following materials would make the best aquitard?

A)Gravel
B)Sandstone
C)Clay
D)Conglomerate

Question 5

________ is the portion of groundwater that is retained as a film on particle and rock surfaces and in tiny openings in the subsurface.

A)Surface tension
B)Infiltration
C)Specific retention
D)Capacity

Question 6

Which of the following is not a factor that will influence infiltration of groundwater?

A)Acidity of precipitation
B)Steepness of the slope
C)Nature of surface material
D)Intensity of rainfall

Question 7

Karst features like caves and sinkholes are an example of ________ porosity.

A)primary
B)secondary
C)superior
D)restricted

Question 8

In order for an aquifer to be useful for reliable water extraction, what kind of porosity and permeability should it have?

A)Low porosity, low permeability
B)High porosity, high permeability
C)Low porosity, high permeability
D)High porosity, low permeability

Question 9

To be a gaining stream, the elevation of the water table must be ________ than that of the surface of the stream.

A)lower
B)higher
C)heavier
D)lighter

Question 10

Which of the following uses the largest percentage of the Earth's groundwater?

A)Mining
B)Hydroelectric power
C)Irrigation
D)Public consumption

Question 11

The ________ is the point in the subsurface where 100% of the pore spaces are filled with water.

A)Vadose Zone
B)Zone of Saturation
C)Zone of Accumulation
D)Capillary Fringe

Question 12

Which of the following materials is most readily dissolved by water?

A)Clay minerals
B)Silica
C)Feldspars
D)Calcite

Question 13

In what spaces or voids does most groundwater reside?

A)Caves
B)Pore spaces
C)Fractures
D)Pore space and fractures

Question 14

Which of the following characteristics is not true of groundwater?

A)Has a constant temperature year round.
B)Rarely contains suspended sediment.
C)Short droughts do not affect the supply.
D)Only occurs underground as large lakes.

Question 15

Which household function has the highest daily water consumption?

A)Dishwashers
B)Showers and baths
C)Clothes washers
D)Toilets

Question 16

How will the water table respond when there is a drought?

A)Water table will rise.
B)Water table will fall.
C)Water table will remain the same.

Question 17

How will the water table respond if it is a wet spring?

A)Water table will rise.
B)Water table will fall.
C)Water table will remain the same.

Question 18

What is porosity?

A)Volume of pore space in a material
B)Ability to transmit water
C)When ice crystals deform and slide past each other
D)Dissolution of carbonate rock due to acid

Question 19

If gravity pulls infiltrating water downward, what force allows water to be pulled upward at the capillary fringe?

A)Static electricity
B)Friction
C)Surface tension
D)Compression

Question 20

What percentage of the Earth's total freshwater is in the form of groundwater?

A)97.2%
B)94%
C)30.1%
D)0)03%

Question 21

The general term used to describe cave deposits is ________.

A)cave pearls
B)dripstone
C)bicarbonate
D)dissolution features

Question 22

What geologic process is responsible for the geothermal features in Yellowstone National Park?

A)Radioactive minerals near the surface
B)Volcanic activity
C)Abnormal volumes of rain
D)Normal geothermal gradient

Question 23

What is the source of much of water in geothermal features such as geysers and hot springs?

A)Precipitation
B)Water vapor from magma
C)Melting glaciers
D)Subterranean lakes

Question 24

Which of the following materials would be the best natural filter, removing contaminants from groundwater over a long period of time?

A)Fractured granite
B)Slightly clayey sand
C)Conglomerate
D)Mica schist

Question 25

Which environmental issue most commonly affects groundwater aquifers in coastal or island areas?

A)Subsidence
B)Dissolution
C)Chemical contamination
D)Saltwater contamination

Question 26

Which acid, found in most groundwater, is responsible for most karst topography worldwide?

A)Hydrochloric
B)Nitric
C)Sulfuric
D)Carbonic

Question 27

What feature develops if a well is withdrawing more groundwater than an aquifer can naturally replace, resulting in a dimple in the water table?

A)Cone of depression
B)Subsidence
C)Contamination
D)Saltwater encroachment

Question 28

What mineral substance makes up most geyser deposits?

A)Travertine
B)Sandstone
C)Sinter
D)Obsidian

Question 29

Which 19^th-century scientist developed the following equation that determines the discharge of an aquifer?

A)Charles Lyell
B)Alfred Wegener
C)Louis Agassiz
D)Henri Darcy

Question 30

California's Central Valley is an important agricultural area for U.S.fruit and vegetable production.Because of the semiarid climate there, farmers must irrigate their crops.Which environmental problem do you anticipate as a result?

A)Saltwater contamination
B)Fluvial erosion
C)Land subsidence
D)Water acidification

Question 31

________ is when groundwater is being replenished.________ is when groundwater is flowing back toward the surface.

A)Recharge; Discharge
B)Drainage; Discharge
C)Dissolution; Recharge
D)Retention; Capacity

Question 32

Which countries/regions outside the United States are famous for their geothermal activity?

A)Brazil, South Africa, and Ukraine
B)Cuba, Italy, and the Philippines
C)Japan, China, and North Korea
D)Iceland, New Zealand, Japan, and Siberia

Question 33

While on vacation, you visit a local Imax theater and see a movie about cave diving in the Yucatan Peninsula.In one of the caves, which is currently filled with water, you notice the divers swimming past some stalactites and stalagmites.If the water table is now above the level of the ceiling of the cave, what does the presence of the cave decorations indicate about past water table levels?

A)The water table was much higher, and the increased water brought in extra material to form the decorations.
B)The water table was much lower, and the features were formed by water dripping from the ceiling into an air-filled chamber.
C)The water table has always been at that level and the cave decorations formed through the fracturing of the ceiling.
D)The water table has always been high, but molten material was able to extrude underwater.

Question 34

What geologic process is responsible for warming the water at nonvolcanic locations such as Hot Springs National Park, Arkansas, and Warm Springs, Georgia?

A)Radioactive minerals near the surface
B)Friction from moving rocks
C)Abnormal volumes of rain
D)Normal geothermal gradient as groundwater circulates at depth

Question 35

A typical rate of groundwater flow for many aquifers is approximately ________.

A)1 cm/day
B)4 cm/day
C)0)5 m/day
D)2 m/day

Question 36

What is the term used to describe the hypothetical line the water in a confined aquifer would rise to if it weren't trapped?

A)Potentiometric surface
B)Hydraulic gradient
C)Darcy's law
D)Discharge

Question 37

What groundwater feature forms where the water table intersects with the Earth's surface, creating a natural outflow of groundwater?

A)Fumarole
B)Sinkhole
C)Lake
D)Spring

Question 38

Which of the following regions is famous for its artesian wells?

A)Central Illinois
B)Florida
C)Western South Dakota
D)Coastal Maine

Question 39

Which of the following accounts for the largest usage of groundwater in the United States?

A)Domestic and municipal water
B)Agriculture and irrigation
C)Cooling reactors at nuclear power plants
D)Manufacturing and industry

Question 40

________ is a term used to describe how the water table around a well becomes lower as water is taken from the subsurface.

A)Depression
B)Saturation
C)Perching
D)Drawdown

Question 41

Aquitards are made of high-conductivity materials such as clay.

Question 42

Stalactites grip tightly to the floor of a cave whereas stalagmites hang from the ceiling.

Question 43

Most caverns are created at or near the water table.

Question 44

When precipitation occurs over a forest, only 25% of the water will make it through the canopy to the forest floor, where other factors may affect how much will infiltrate.

Question 45

Which of the following is an example of a speleothem?

A)Stalagmite
B)Sinkhole
C)Spring
D)Hot spring

Question 46

The water in the majority of wells cannot rise above the level of the water table on its own.

Question 47

Wells are drilled into the subsurface to remove water from the unsaturated zone.

Question 48

The majority of groundwater occurs as underground rivers.

Question 49

Caves can only form in limestone.

Question 50

If a groundwater well pumps enough water to draw down the water table, the drawdown will increase the slope of the water table, which will increase the velocity of groundwater.

Question 51

Lakes and streams are surface expressions of the water table.

Question 52

In semiarid to arid regions, groundwater is considered a nonrenewable resource because it isn't replaced at the same rate as it is withdrawn.

Question 53

The water table is the uppermost 3 feet of the zone of saturation.

Question 54

Clay's porosity is high, but its permeability is low, which means that it has a low specific yield.

Question 55

How do scientists map the water table?

Question 56

Freshwater is less dense than saltwater.

Question 57

A geyser is a type of artesian well.

Question 58

Groundwater is important as an erosional agent.

Question 59

Groundwater migrates from areas of low pressure to areas of high pressure.

Question 60

The water table undulates with the ground surface.It is low where the ground surface is high and high where the ground surface is low.

Question 61

Assume that chemical pollutants have been illegally dumped in the major river on the left side of this image.Will those pollutants infiltrate and contaminate any other bodies of water? If so, which ones?

A)Stream
B)Left-hand lake
C)Right-hand lake
D)None.The major river is a discharge point

Question 62

Compare and contrast a geyser and a hot spring.

Question 63

Undulations of the water table mimic those of the ground surface.What would happen to those undulations in the water table if all rain were to cease?

Question 64

Explain how groundwater can sustain streams even during a long drought.

Question 65

This image shows the gradient of the water table between Well A and Well B.Please note that the label for each well also displays the elevation of the water table in that well.Using the information present in the figure, calculate the hydraulic gradient of this cross section.

A)8 m/km
B)11.7 m/km
C)21.9 m/km
D)32 m/km

Question 66

What is different about mineral deposits at Mammoth Hot Springs compared to other geothermal features in Yellowstone National Park? From which rock were these mineral deposits derived?

Question 67

Examine the groundwater flow patterns around Point X.Into which bodies of water (if any)will water that infiltrates at Point X eventually discharge?

A)Stream
B)Left-hand lake
C)Right-hand lake
D)Major river

Question 68

Which has a higher porosity: sand or sandstone? Why?

Question 69

Assume that chemical pollutants have been buried at Point Y.The heavy dashed arrow shows the path of infiltration the pollutants followed.Which other bodies of water will be contaminated by these pollutants?

A)Both lakes
B)The major river and the left-hand lake
C)All bodies of water will be contaminated.
D)The contamination is flowing below the aquitards, so none will be contaminated.

Question 70

What localized lowering of the water table is present in this figure?

A)Ground subsidence
B)Cone of depression
C)Sinkhole
D)Hot spring

Question 71

Some bottled water companies advertise that their product is clean and pure because it comes from an artesian well.Discuss the validity of this statement.

Question 72

Major coastal cities such as Charleston, South Carolina, have to find a delicate balance between supplying enough water for a healthy, growing city and preventing contamination of their groundwater supplies with saltwater due to overpumping.What steps could be taken to counteract the effects of saltwater contamination without abandoning the well? Explain.

Question 73

Igneous and metamorphic rocks do not form with voids or pore spaces where groundwater can reside.However, these rocks can often both store and transport groundwater.What voids would make up the secondary porosity of igneous and metamorphic rocks?

Question 74

What feature is highlighted with an arrow in this image?

A)Sinkhole
B)Perched water table
C)Cone of depression
D)Ground subsidence

Question 75

What is the difference between a flowing artesian well and a nonflowing artesian well?

Question 76

Explain the process of cave formation.

Question 77

Assume that the irrigation well in the middle of this image was installed by a seed corn company and not by the farmers who own the local wells on either side.If irrigation were stopped immediately, would this localized lowering recover immediately? Why or why not?

A)Yes.Water from other parts of the aquifer could replace what was lost.
B)No.The average aquifer has a groundwater flow rate of 4 cm/day.
C)Yes.The reduced pressure in the aquifer would allow the groundwater to flow faster.
D)No.Now that irrigation has stopped, there is no suction necessary to draw the water.

Question 78

Explain how artesian wells are created.Your explanation should include a discussion of how they get recharged.

Question 79

What physical features are evidence of a karst landscape?

Question 80

A severe drought in 2012 devastated much of the United States, causing crop failure, lower stream levels, and the drying and cracking of the ground.Obviously, a great deal of water was needed to end this drought.At the end of August of that year, Hurricane Isaac made landfall along the Gulf Coast of Louisiana and Mississippi and proceeded to move up the Mississippi River and across central and northern Illinois by August 31 and September 1, precipitating large volumes of rain as it moved.How did the transit of Hurricane Isaac affect the drought (Did it end the drought?)? How would groundwater levels change? Explain your answers.