quiz 1

A stream begins at an elevation of 200 meters and flows a distance of 400 kilometers to the ocean? What is the average gradient?

.5

A stream begins at an elevation of 200 meters and flows a distance of 400 kilometers to the ocean? What is the average gradient?

0.5m/km `

Which one of the following logically explains why parts of some cavern systems are aerated?

A nearby, downcutting stream lowered the water table after the caves had formed.

________ account for the largest usage of groundwater in the United States.

Agriculture and irrigation

The ________ river has the largest discharge of any in the world.

Amazon

________ account for the largest usage of groundwater in the United States.

Amazon

Which of the following statements concerning unconfined aquifers on barrier islands and atolls is correct?

Any salty water in the aquifer will rise if the water table is lowered by pumping.

1) ________ is not part of the hydrologic cycle.

Calcium carbonate dissolving in soil water and groundwater

________ describes the total sediment load transported by a stream.

Capacity

What is the relationship between drawdown and the cone of depression associated with a pumping well?

Drawdown is the distance between the original water table and the water level in the well.

________ are components of the hydrologic cycle that release water vapor directly to the atmosphere.

Evaporation and transpiration

________ is an abandoned, cutoff, meander loop.

Oxbow

________ controls the ease (or difficulty) of groundwater transmission through a porous material.

Permeability

________ describes the particle transport mode in streams intermediate between suspension and rolling along the bottom.

Saltation

Which one of the following statements is correct? Sea level drops when water is stored in expanding ice sheets and continental glaciers. Sea level rises when water is added to the oceans through increased rainfall and increased Sea level drops when evaporation rates increase over the oceans and when this extra, atmospheric moisture falls on land as rain. Sea level rises when water is stored in expanding ice sheets and continental glaciers.

Sea level drops when water is stored in expanding ice sheets and continental glaciers.

________ make up the suspended loads of most rivers and streams.

Silt and clay-sized, detrital grains

________ are specific features of karst topography.

Streams flowing into depressions and continuing underground

________ generally constitutes the highest percentage of the annual sediment load moved by a stream.

Suspended load

Which of the following can logically be concluded by speleothems/dripstone hanging from a cave roof?

The cave roof was above the water table when the speleothems formed.

A natural, meandering, river channel is modified into a more or less straight and smooth, canal-like channel. Which of the following statements is correct?

The natural channel had a lower gradient and higher friction than the straight channel.

Which one of the following statements is true concerning natural levees?

They are mostly fine sand and silt that build up during floods.

Which of the following best describes how geysers erupt?

With a slight reduction in pressure, water in a saturated, natural conduit suddenly boils, sending a plume of steam and hot water into the air above the vent.

Where are the most extensive geothermal features in the world?

Yellowstone

The water table is ________.

a boundary between saturated rock below and unsaturated rock above

A perched water table develops when ________.

a horizontal aquitard above the regional water table lies below an aquifer

An aquifer is ________.

a saturated, porous, and permeable layer or stratum

A disappearing (sinking) creek is ________.

an influent stream in a karst area

Which common, rock-forming mineral or mineral group is most readily dissolved by groundwater?

calcite

A dam and reservoir are constructed on a graded river. What will happen?

deposition upstream from the dam; channel downcutting below

At the head of a delta, the major channel splits into smaller channels that follow different paths to the sea. These smaller channels are known as ________.

distributaries

After ice sheets and glaciers, ________ contain(s) the next highest percentage of Earth's freshwater.

groundwater

________ are characteristics found in all good aquifers.

high porosity and high permeability

Which one of the following does not apply to stream turbulence and average velocity?

laminar flow; dissolved load

The aerated zone ________.

lies above the water table

Which of the following geologic materials would have the highest groundwater velocities and be least effective in removing unwanted pollutants from the water?

limestone; numerous solution channels and fractures widened by dissolution

Which of the following features characterize wide streams and valleys?

natural levees; broad floodplains

Where is erosion concentrated along a meandering stream?

on the outer parts of the meander loops or bends

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

pressure gradient or hydraulic gradient

A ________ stream pattern is developed only on growing mountains like volcanoes or where the land surface is tectonically doming upward.

radial

Which of the following is not a general characteristic of groundwater?

rarely contains dissolved constituents

________ would have the largest capacity to naturally remove sewage pollutants.

slightly clayey sand

A ________ is the icicle-like speleothem that grows down from the roof of a cavern.

stalactite

What is the drop in water surface elevation divided by the distance the water flows?

stream gradient

The term karst topography was first used in ________.

the Republic of Slovenia, a province of the former Yugoslavia

Which of the following is the correct definition of stream gradient?

the drop in elevation of a stream divided by the distance the water travels

A stream is said to be perennial and effluent when ________.

the local water table is above the channel bottom year round

Excessive groundwater withdrawals can cause ________.

the water table drops or declines in elevation

A ________ stream pattern develops on lands underlain by tilted or folded, alternating hard and soft, sedimentary strata.

trellis

Which of the following is the only correct response concerning the location and causes of the extraordinarily severe, 1993, flooding on the Mississippi River and tributaries? lower basin; heavy rains in late spring and early summer upper basin; rapid melting of an unusually deep snow pack in early spring lower basin; very heavy, late summer rains associated with a severe hurricane upper basin; very heavy, sustained rainfall in the late spring and early summer

upper basin; very heavy, sustained rainfall in the late spring and early summer

An artesian well is one in which ________.

water rises above the top of the aquifer without any pumping