Groundwater

Which of the following defines an aquifer?

A saturated, porous, and permeable layer or stratum

Which of the following describes an artesian well?

A well in which water rises above the top of the aquifer without any pumping

Which of the following describes a disappearing (sinking) creek?

An influent stream in a karst area

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

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

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

Calcite

Which of the following describes the configuration of an unconfined water table around a pumping well?

Cone of depression

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.

How would hazardous substances such as gasoline, kerosene, ethyl alcohol, pesticides, and acids that accidentally entered a groundwater system behave?

Gasoline and kerosene would float on the water table; ethyl alcohol would dissolve and disperse in the groundwater.

Which one of the following is not a speleothem?

Geyserite

What reservoir(s) contain(s) the next-highest percentage of Earth's freshwater after ice sheets and glaciers?

Groundwater

Name two characteristics found in all aquifers.

High porosity and high permeability

The hot spring deposits at Mammoth Hot Springs, Yellowstone National Park, are travertine. What rock probably lies somewhere beneath the hot springs?

Limestone

What characteristic of rocks and/or soil controls the ease (or difficulty) of groundwater transmission?

Permeability

What term describes the volume of voids or open spaces in a rock or unconsolidated material?

Porosity

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

Pressure gradient or hydraulic gradient

Which of the following materials would have the best capability to naturally remove sewage pollutants?

Slightly clayey sand

What is the name of an icicle-like speleothem that grows down from the roof of a cavern?

Stalactite

Which of the following are specific features of karst topography?

Streams flow into depressions called sinkholes and continue to flow underground.

Which of the following statements defines the aerated, or vadose, zone?

The aerated, or vadose, zone lies above the water table.

Which of the following describes the water table?

The boundary between saturated rock below and unsaturated rock above

What is an unconfined water table?

The boundary between the aerated, or vadose, zone above and the saturated zone below

What can be a result of excessive groundwater withdrawal?

The water table may drop or decline in elevation.

When will a perched water table develop?

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

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 located?

Yellowstone National Park, United States