Question 1

The porosity of vesicular basalt is about 30%;however,when water is poured on it,the water does not come out the other side.How is this possible?

Accepted Answer

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. 
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. B

Question 2

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?

Accepted Answer

A) Add acid to the layer to dissolve the rock and create connections between the pores. 
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. 
A) Add acid to the layer to dissolve the rock and create connections between the pores. 
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. B

Question 3

Land subsidence is likely when ________.

Accepted Answer

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

Question 4

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

Accepted Answer

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. 
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 5

Which statement best fits the figure below?

Accepted Answer

A) The oases formed next to or above permeable rock.The confined aquifer has low porosity and permeability. 
B) The oases formed next to or above impermeable rock.The confined aquifer has high porosity and permeability. 
C) The oases formed next to or above impermeable rock.The confined aquifer has low porosity and permeability. 
D) The oases formed next to or above permeable rock.The confined aquifer has high porosity and permeability. 
A) The oases formed next to or above permeable rock.The confined aquifer has low porosity and permeability. 
B) The oases formed next to or above impermeable rock.The confined aquifer has high porosity and permeability. 
C) The oases formed next to or above impermeable rock.The confined aquifer has low porosity and permeability. 
D) The oases formed next to or above permeable rock.The confined aquifer has high porosity and permeability.

Question 6

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 chose to drill into the confined aquifer.Why?

Accepted Answer

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. 
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 7

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

Accepted Answer

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 
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 8

Material through which water readily flows is termed ________.

Accepted Answer

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

Question 9

Pumping vast quantities of water locally ________.

Accepted Answer

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 
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 10

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

Accepted Answer

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) The arsenic is not actually there;it does not show up in groundwater. 
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) The arsenic is not actually there;it does not show up in groundwater.

Question 11

An impermeable layer of rock or sediment is termed a(n)________ in hydrogeologic contexts.

Accepted Answer

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

Question 12

The dissolution of rock produces ________.

Accepted Answer

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

Question 13

If a material is highly permeable,it ________.

Accepted Answer

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

Question 14

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?

Accepted Answer

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. 
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 15

The majority of liquid freshwater within Earth exists in ________.

Accepted Answer

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

Question 16

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

Accepted Answer

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

Question 17

During a particularly cold winter in Florida,the temperatures remained below freezing for several weeks.To avoid freeze damage to the crops,farmers used well water to continuously spray the crop and maintain a protective coating of ice around the crop.Shortly after this long cold snap,sinkholes began forming throughout the region.Were these events linked?

Accepted Answer

A) No;watering crops does not cause the formation of sinkholes. 
B) No;sinkholes form in a karst landscape,which farmers cannot farm on. 
C) Yes;the farmers removed too much water from the aquifers and induced subsidence. 
D) Yes;the farmers added too much weight to the surface and induced subsidence. 
A) No;watering crops does not cause the formation of sinkholes. 
B) No;sinkholes form in a karst landscape,which farmers cannot farm on. 
C) Yes;the farmers removed too much water from the aquifers and induced subsidence. 
D) Yes;the farmers added too much weight to the surface and induced subsidence.

Question 18

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

Accepted Answer

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. 
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 19

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

Accepted Answer

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

Question 20

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 and growing city 50 miles to the north.What can you conclude is the most likely reason for your well to become dry?

Accepted Answer

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. 
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.

Exam 19: A Hidden Reserve: Groundwater

The porosity of vesicular basalt is about 30%;however,when water is poured on it,the water does not come out the other side.How is this possible?

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?

Land subsidence is likely when ________.

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

Which statement best fits the figure below?

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 chose to drill into the confined aquifer.Why?

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

Material through which water readily flows is termed ________.

Pumping vast quantities of water locally ________.

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

An impermeable layer of rock or sediment is termed a(n)________ in hydrogeologic contexts.

The dissolution of rock produces ________.

If a material is highly permeable,it ________.

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?

The majority of liquid freshwater within Earth exists in ________.

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

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

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

Cosmology and the Birth of Earth

Journey to the Center of the Earth

Drifting Continents and Spreading Seas

The Way the Earth Works: Plate Tectonics

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

Pages of Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

The Wrath of Vulcan: Volcanic Eruptions

A Violent Pulse: Earthquakes

Crags,cracks,and Crumples: Crustal Deformation and Mountain Building

Deep Time: How Old Is Old

A Biography of Earth

Squeezing Power From a Stone: Energy Resources

Riches in Rock: Mineral Resources

Unsafe Ground: Landslides and Other Mass Movements

Streams and Floods: the Geology of Running Water

Restless Realm: Oceans and Coasts

An Envelope of Gas: Earths Atmosphere and Climate

Dry Regions: the Geology of Deserts

Amazing Ice: Glaciers and Ice Ages

Global Change in the Earth System

Introducing Rocks

a Surface Veneer: Sediments and Soils

the Rock Cycle in the Earth System

the Earths Interior, revisited: Seismic Layering, gravity, and the Magnetic Field

Memories of Past Life: Fossils and Evolution

Ever-Changing Landscapes and the Hydrologic Cycle

Filters

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