Visualizing Physical Geography Chapter 11

Front 1

Infiltration

Back 1

Absorption and downward movement of precipitation into the soil and regolith

Front 2

Runoff

Back 2

Flow of water from continents to oceans through stream flow and ground-water flow.

Front 3

Ground water

Back 3

Subsurface water in the saturated zone that moves under the force of gravity.

Front 4

Water table

Back 4

Upper limit of the body of ground water; marks the boundary between the saturated and unsaturated zones.

Front 5

Aquifer

Back 5

Layer of rock or sediment that contains abundant freely flowing ground water.

Front 6

Stream

Back 6

Long, narrow body of flowing water moving along a channel to lower levels under the force of gravity.

Front 7

Drainage system

Back 7

A branched network of stream channels and adjacent land slopes converging to a single channel at the outlet.

Front 8

Overland flow

Back 8

Runoff that flows down the slopes of the land in broadly distributed sheets.

Front 9

Floodplain

Back 9

A broad belt of low, flat ground bordering a river channel that floods regularly.

Front 10

Lake

Back 10

Body of standing water that is enclosed on all sides by land.

Front 11

Stream flow

Back 11

Water runs along a narrow channel between banks.

Front 12

Explain the hydrologic cycle.

Back 12

Front 13

How are karst landscapes created?

Back 13

Water slowly erodes limestone below the surface, forming deep underground caverns. The caverns can then collapse, creating a unique type of landscape. When the caverns collapse they are called sinkholes. (11.7)

Front 14

Explain how ground water can become contaminated from waste.

Back 14

When waste is situated in the unsaturated zone, it reacts with rainwater that infiltrates the ground surface. This water picks up a wide variety of chemical compounds from the waste and carries them down to the water table.

Front 15

How do wells affect the water table?

Back 15

Wells lower the water table because they pump water out faster than the water table is recharged by water infiltrating downward.

Front 16

How does a drainage system work?

Back 16

As runoff moves to lower and lower levels and eventually to the sea, it becomes organized into a branched network of stream channels. This network and the sloping ground surfaces next to the channels that contribute overland flow to the streams together are called a drainage system.

Front 17

How do salt flats form?

Back 17

In lakes with no outlet, streams bring water in with dissolved solids. Since evaporation only removes pure water, the salts remain behind. Salt flats form when the climate encourages evaporation rather than input into the lake. The dry lake is then a shallow empty basin covered with salt deposits instead of a lake.

Front 18

What percent of the hydrosphere's total water is fresh water?

Back 18

3%

Front 19

Where is most of the fresh water found?

Back 19

Locked into ice sheets and mountain glaciers.

Front 20

What are the three primary paths that precipitation can take after hitting the soil layer?

Back 20

1. Infiltration 2. Surface runoff 3. Evapotranspiration

Front 21

Evapotranspiration

Back 21

a term describing the transport of water into the atmosphere from surfaces, including soil (soil evaporation), and from vegetation (transpiration).

Front 22

Percolation

Back 22

When the water on the surface of the earth seeps down underground

Front 23

What happens when the water table remains stable?

Back 23

The flow of water released to streams and lakes balances the flow of water percolating down into the water table.

Front 24

Aquiclude

Back 24

An impermeable body of rock or stratum of sediment that acts as a barrier to the flow of groundwater.

Front 25

Artesian well

Back 25

A porous sandstone bed (aquifer) is sandwiched between two impervious rock layers (aquicludes). Precipitation provides water that saturates the sandstone layer. Since the elevation of the well that taps the aquifer is below that of the range of hills feeding the aquifer, pressure forces water to rise in the well.

Front 26

Karst

Back 26

Landscapes where there are numerous sinkholes and no small surface streams.

Front 27

Cone of depression

Back 27

The depression in the water table around a well defining the area of influence of the well. (See 11.12)

Front 28

Drawdown

Back 28

The difference in height between the cone tip and the original water table. (See 11.12)

Front 29

Explain how ground water can become contaminated from saltwater.

Back 29

Fresh water is less dense than saltwater, so a layer of saltwater from the ocean can lie below a costal aquifer. When the aquifer is depleted, the level of saltwater rises and eventually reaches the well from below, making the well unusable.

Front 30

Sheet flow

Back 30

Where the soil or rock surface is smooth and the flow is a continuous thin film. *form of overland flow

Front 31

Stream channel

Back 31

A narrow trough, shaped by the forces of flowing water.

Front 32

If a stream channel is straight and symmetrical, where is the line of maximum velocity?

Back 32

Midstream, because water of the outer ends of the stream are slowed by the friction with the channel walls.

Front 33

If a stream channel is curved, where is the line of maximum velocity?

Back 33

Toward the bank on the outside of the curve.

Front 34

What will the stream channel be like in stretches of rapids?

Back 34

Narrow and shallow.

Front 35

Drainage divide

Back 35

The boundary between slopes that contribute water to different streams or drainage systems.

Front 36

Drainage basin or watershed

Back 36

The pear-shaped drainage divide that bounds the entire drainage system.

Front 37

In what two ways does the growth of cities and suburbs cause flooding?

Back 37

1. When cities are built, the ground is covered with buildings and pavements. Water cannot infiltrate this material so overland flow increases, making flooding more common during heavy storms. 2. Storm sewers carries storm runoff from paved areas directly to streams through large underground pipes. This shortens the time it takes runoff to travel to channels while the proportion of runoff is increased by the expansion in impervious surfaces. Together, these changes reduce the lag time of urban streams and increase their peak discharge levels.

Front 38

What happens when the discharge of a river cannot be accommodated within its normal channel?

Back 38

Water spreads over the adjoining ground.

Front 39

Lakes can disappear by what two processes (or a combination of both)?

Back 39

1. Lakes that have stream outlets will be gradually drained as the outlets are eroded to lower levels. 2. Climate changes- if precipitation is reduced, or temperatures and net radiation increase, evaporation can exceed input and the lake can dry up.

Front 40

In the U.S., what percent of the groundwater used for drinking comes from karst aquifers?

Back 40

40%

Front 41

What are six types of groundwater abuse?

Back 41

1. excessive pumping 2. Rapid withdrawal 3. streamflow depletion 4. land subsidence 5. saltwater intrusion 6. anthropogenic contamination.

Front 42

When does land subsidence occur?

Back 42

Land subsidence occurs when large amounts of ground water have been withdrawn from certain types of rocks, such as fine-grained sediments. The rock compacts because the water is partly responsible for holding the ground up. When the water is withdrawn, the rocks falls in on itself.

Front 43

What is streamflow depletion?

Back 43

The amount of water that flows into a valley, or onto a particular land area, minus the water that flows out the valley or off from the particular land area

Front 44

Effluent streams

Back 44

Streams that get their water from the groundwater.

Front 45

Influent streams

Back 45

Streams that the water from the stream goes into the water table.

Front 46

What regions are effluent streams found in?

Back 46

Humid

Front 47

What regions are influent streams found in?

Back 47

Arid

Front 48

What problems are associated with groundwater mining?

Back 48

Groundwater mining exceed ability to recharge and collapses aquifers.

Front 49

How does groundwater mining collapse aquifers?

Back 49

There is a loss of support of water in pore spaces.

Front 50

What are some examples of collapsed aquifers in the United States?

Back 50

Ogallala Aquifer, Great Plains Aquifer.

Front 51

What is a point source?

Back 51

place where pollution occurred- someone goes out and dumps a pollutant at a particular spot

Front 52

In the U.S. what causes the highest concentrations of groundwater pollution?

Back 52

1. Agricultural runoff (animal feces, pesticides, etc) 2. old sanitary landfills