Deck 19: A Hidden Reserve: Groundwater

Question 1

In the figure below,where would be the best place to locate a well that would supply the most water?

A) A
B) B
C) C
D) D

Answer 1

B

Question 2

If a material is porous,it ________.

A) will be permeable as well
B) will be impermeable
C) may be permeable or impermeable
D) would not be permeable or impermeable

Answer 2

C

Question 3

Material through which water readily flows is termed ________.

A) fluent
B) porous
C) permeable
D) fluid

Answer 3

C

Question 4

Which of the following lists correctly orders the three types of subsurface water from shallowest to deepest?

A) groundwater,soil moisture,vadose zone water
B) soil moisture,groundwater,vadose zone water
C) groundwater,vadose zone water,soil moisture
D) soil moisture,vadose zone water,groundwater

Question 5

If a material is highly permeable,it ________.

A) must be porous
B) cannot be porous
C) must be fractured
D) must either have substantial porosity or be fractured

Question 6

Rock or sediment between the water table and the land surface represents a(n)________.

A) aquitard
B) confined aquifer
C) unconfined aquifer
D) unsaturated zone

Question 7

In many areas with karst terrain,people use sinkholes as places to dump garbage.What effect might this practice have on the groundwater supply?

A) None; sinkholes are not connected to groundwater sources.
B) It clogs the sinkholes so that water cannot percolate into the groundwater.
C) It could contaminate the groundwater in unconfined aquifers only.
D) It could contaminate the groundwater in any or all aquifers in the area.

Question 8

An aquifer has ________ porosity and ________ permeability.

A) low; high
B) high; low
C) low; low
D) high; high

Question 9

You have a choice to drill your water well into a shallower unconfined aquifer or a deeper confined aquifer.Drilling deeper will cost more money; however,you choose to drill into the confined aquifer.Why?

A) The confined aquifer will most likely have a higher water quality.
B) The confined aquifer will most likely have a higher permeability.
C) The confined aquifer will not be subject to overpumping.
D) The confined aquifer will contain more water.

Question 10

The dissolution of rock produces ________.

A) primary porosity
B) primary permeability
C) secondary porosity
D) a reduction in primary porosity

Question 11

The porosity of vesicular basalt is about 25%; however,when water is poured on it,the water does not come out the other side.How is this possible?

A) The vesicles in basalt are filled with sediments and thus cannot hold water.
B) The vesicles in basalt are not connected,so it has no permeability.
C) The minerals in the basalt react chemically with the water to produce gases.
D) Vesicular basalt is similar to a sponge and will soak up all the water.

Question 12

Unfractured vesicular basalt has ________ porosity and ________ permeability.

A) high; high
B) low; high
C) high; low
D) no; high

Question 13

A person is digging a hole,when the hole suddenly starts to fill with water.What have they found?

A) the capillary zone
B) the vadose zone
C) the water table
D) an aquitard

Question 14

The majority of liquid freshwater within the Earth exists in ________.

A) lakes
B) rivers and streams
C) groundwater
D) atmospheric clouds

Question 15

The figure below shows the Dakota and Ogallala aquifers along with interlayered shale deposits.What likely occurred in the area to produce the alternating shale and sandstone layers?

A) metamorphism to produce shale
B) transgression and regression
C) intrusion of shale between sandstone
D) precipitation of clay into the shale layer

Question 16

The water table surface mimics the topography in an area because ________.

A) hydraulic head forces it to stay close to the surface
B) the permeability is lowest in hilly areas
C) groundwater cannot penetrate below aquitards
D) groundwater flow rates are so low

Question 17

Porosity is best described by which of the following?

A) the hardness of a rock or sediment
B) the chemistry of a fluid in a rock or sediment
C) the amount of open space in a rock or sediment
D) the ability of fluids to pass through a substance (rock or sediment)

Question 18

Imagine you have a layer of limestone with high porosity but low permeability.What can you do to increase its permeability to allow water to be pumped from the layer and used as a source of drinking water?

A) Add salt to the water to increase its density so that it flows more readily.
B) Drill down to the layer and set off explosives in the hole to fracture the rock.
C) Remove the overburden so that there will be less pressure trapping the water.
D) Increase the hydraulic conductivity by adding metals to the water.

Question 19

If an intrusive igneous rock is unfractured,it serves as a(n)________ in local hydrogeology.

A) aquifer
B) aquitard
C) artesian well
D) perched aquifer

Question 20

An impermeable layer of rock or sediment is a(n)________.

A) aquitard
B) confined aquifer
C) unconfined aquifer
D) unsaturated zone

Question 21

A periodic explosive eruption of steam and water from within the ground up through the surface is termed a(n)________.

A) artesian well
B) geyser
C) spring
D) recharge area

Question 22

You are drilling a water well when you hit water at a much shallower level than you expected.What have you likely found?

A) an artesian aquifer
B) a perched aquifer
C) a natural spring
D) an aquiclude

Question 23

A flowing artesian well is one that ________.

A) discharges groundwater at the ground surface without pumping
B) has its intake sited within the vadose zone of an unconfined aquifer
C) has its intake sited within the unsaturated zone of an unconfined aquifer
D) has its recharge area at an elevation below sea level

Question 24

The elevation of the water table ________.

A) is a constant for a given area so long as the topography remains the same
B) may rise during times of drought and sink during rainy periods
C) may rise during rainy periods and sink during droughts
D) is completely unpredictable

Question 25

Any place where groundwater naturally flows out of the Earth's surface is termed a(n)________.

A) artesian well
B) geyser
C) spring
D) recharge area

Question 26

You have a choice to drill your water well into a shallow unconfined aquifer or a deeper artesian aquifer.Drilling deeper will cost more money; nevertheless,you chose to drill into the artesian aquifer.Why?

A) The artesian aquifer will have a higher permeability.
B) The artesian aquifer will not be subject to overpumping.
C) The artesian aquifer will flow on its own,without a pump.
D) The artesian aquifer will contain more water for your use.

Question 27

For a well to function properly,it must be drilled below the water table and into a(n)_________.

A) aquifer
B) aquitard
C) spring
D) geyser

Question 28

Pumping vast quantities of water locally ________.

A) raises the local water table
B) lowers the local water table,forming a cone-shaped depression
C) lowers the local water table,forming a cylindrical depression
D) does not affect the water table

Question 29

Ultimately geysers erupt because of the __________.

A) periodic opening and closing of a fracture.
B) mixing of hot and cold water to form steam.
C) decrease in pressure as water rises,allowing it to flash to steam.
D) increase in pressure from the hot water,which prevents boiling.

Question 30

Hot springs can be formed by the heating of groundwater by magma or by ________.

A) decompression heating
B) infrared heating by the Sun
C) the geothermal gradient
D) heating by the core

Question 31

Where would you expect to find geysers?

A) Iceland
B) England
C) Antarctica
D) Greenland

Question 32

Hard water results from relatively high concentrations of dissolved ________.

A) calcium and magnesium
B) sodium and lithium
C) sodium
D) potassium

Question 33

The hydraulic gradient in Darcy's Law is essentially the same as which of the following?

A) the slope of a line
B) the quadratic equation
C) a Pythagorean triangle
D) the area of a triangle

Question 34

What does it mean if the potentiometric surface does NOT reach above the ground surface?

A) The aquifer does not have any recharge into it and thus is dry.
B) There will not be any artesian wells or springs associated with the aquifer.
C) It will not be possible to pull water out of the aquifer from any type of well.
D) The aquifer does not have a high enough permeability to produce water.

Question 35

The rate of groundwater flow per unit area through a body of rock or sediment depends ________.

A) only on the slope of the local water table
B) only on the porosity of the rock or sediment
C) on the slope of the water table and the porosity of the rock or sediment
D) on the slope of the water table and the permeability of the rock or sediment

Question 36

Why does an artesian well flow without pumping?

A) The water table is at the surface in an artesian aquifer.
B) The hydraulic head is very low in the aquifer.
C) The water in an unconfined aquifer is pressurized.
D) The water in a confined aquifer is pressurized.

Question 37

As a rule,groundwater always flows from areas of ________.

A) greater land elevation to those of lesser land elevation
B) lesser land elevation to those of greater land elevation
C) greater hydraulic head to those of lesser hydraulic head
D) lower hydraulic head to those of greater hydraulic head

Question 38

Hot groundwater is mineralized because

A) minerals cannot precipitate in hot water.
B) the hot water dissolves minerals.
C) cold water cannot dissolve minerals.
D) hot water flows deeper in the Earth.

Question 39

You are testing the groundwater quality of an aquifer and find that it has high amounts of arsenic.What is the likely source?

A) The arsenic comes from the dissolved minerals in the aquifer rock.
B) The arsenic comes from the reaction of the water with your testing supplies.
C) The arsenic is being poured into the groundwater to poison the town.
D) All groundwater contains high amounts of arsenic.

Question 40

Rates of groundwater flow are ________ than stream flow because the water ________.

A) higher; can flow through large caverns
B) higher; does not have any obstacles to overcome
C) lower; contains dissolved ions that slow it down
D) lower; must make its way through tiny pore spaces

Question 41

Consult the figure below.If someone were to dump chemicals into a dry river,what would happen to those chemicals?

A) They would evaporate into the atmosphere and no longer be a danger.
B) They would remain in the soil but would not make it into the groundwater.
C) They would seep into the groundwater but flow away from the city's wells.
D) They would end up flowing with the groundwater toward the city's wells.

Question 42

Consult the figure below.What will eventually happen to the Everglades if the people of Miami and Fort Myers do not stop using the water?

A) It will shift toward Lake Okeechobee.
B) It will eventually dry up and disappear.
C) It will shift to be closer to Fort Myers.
D) It will be replenished by recharge.

Question 43

In the image below,label the confined aquifer,the unconfined aquifer,and the aquitard.If you were to drill a well for personal use in this region,which of these three layers would you access? Why?

Question 44

The images below are of two different geological scenarios in which springs could form.Describe the similarities and differences between these two scenarios.

Question 45

Where does the heat come from to create hot springs?

Question 46

What are porosity and permeability,and how do they affect the rate of groundwater flow?

Question 47

The commercial distribution of bottled "spring water" has become a major business worldwide,and many people think that this water offers health benefits.Evaluate this belief.How is spring water different from groundwater?

Question 48

A(n)________ aquifer is more likely to be contaminated than a(n)________ aquifer.

A) confined; unconfined
B) unconfined; confined
C) artesian; confined
D) artesian; unconfined

Question 49

Vesicular basalt has high porosity.Would this basalt then make a good aquifer? Why or why not?

Question 50

List and describe one possible effect from overpumping.

Question 51

The majority of large cave and karst systems have resulted from ________ etching into ________.

A) carbonic acid; limestone
B) ascorbic acid; dolostone
C) phosphoric acid; shale
D) sea water; rock salt

Question 52

Topography dominated by depressions formed by the collapse of caves is termed a ________.

A) valley and ridge province
B) karst landscape
C) horst and graben landscape
D) speleothem formation

Question 53

Label the three zones that water moves through as it percolates into the Earth on the image below.Also include where the water table is by marking it with an arrow.

Question 54

Imagine that some of the wells around a city have begun to show elevated levels of a toxic substance.Without knowing what the toxic substance is,how can you determine what the source of the chemicals might be?

A) Without knowing what the toxic chemical is,it would be impossible to pinpoint where the source is.
B) Determine if there are any chemical factories in the area and report them to the authorities.
C) Determine which wells show the chemicals and which do not and use that data to track the flow of the water.
D) Determine which well shows the highest concentration and determine the closest source to that well.

Question 55

The majority of caves are formed by the dissolution of bedrock ________.

A) above the water table
B) just below the water table
C) more than 10 m below the water table
D) more than 10 m above the water table

Question 56

Land subsidence is likely when ________.

A) groundwater recharge occurs
B) the calcium and magnesium content of groundwater increases
C) the water table raises
D) pumping lowers the water table

Question 57

Explain how limestone caves are formed,making sure to include the name of the acids involved and how they form.

Question 58

On the image below,identify the regions of discharge and recharge,and label the water table.Then draw arrows showing the flow of groundwater.

Question 59

In addition to its immense size,what else is unusual about Carlsbad Caverns in southeastern New Mexico?

A) Geologists think the system was produced by sulfuric acid rather than carbonic acid.
B) The caverns are within a deposit of rock salt rather than limestone.
C) The caverns were formed within the span of just a few days in 1937.
D) Although there are conduits to the surface,the caverns do not host a population of bats.

Question 60

For several generations,your family has lived on a farm with a water well.There has never been a problem with the water supply in the past; however,your well has now gone dry.There are several small farms nearby and a large,growing city 50 miles to the north.What can you conclude is the most likely reason for your well to become dry?

A) The farmers nearby have suddenly started using much more water than they used to.
B) The growth of minerals in pore spaces in the aquifer rock has decreased its permeability.
C) As the city grew larger,more wells were drilled and water was overpumped,thus lowering the water table.
D) The water has stopped infiltrating into the ground because of the overuse of pesticides.