Exam 2 Review

They hydrologic cycle ___.
Describes a primary mechanism of the movement of energy as well as the movement of water from one part of the globe to another.
What proportion of the Earth's surface water is fresh water found in streams, lakes, and wetlands?
Less than 1 percent.
Stream gradient, discharge, and ____ determine the velocity of a stream.
Channel shape
A stream's discharge is ___.
Greatest during a time of flood.
Ions dissolved in a stream are called ___.
Dissolved load.
Boulders, cobbles, and sand are carried by a stream as ___.
Bed load.
Most sediment is carried in most streams as ____.
Suspended load.
The water on the outside of a stream curve moves ___.
Faster than the water on the inside.
The velocity in a stream is greatest:
At the center near the surface
The 100-year flood is defined as:
A flood that has a .01 percent chance of happening at any time.
The region ultimately drained by a single river is a ___.
Drainage basin.
Groundwater represents how much of the world's fresh water?
About 1%
Layers that readily transmit groundwater are called ___.
An aquifer is ___.
Both porous and permeable
The process by which surface water becomes groundwater is called ___.
Hydraulic conductivity (permeability) characterizes the ___.
Ease with which a geologic material can move or transmit water.
In the unsaturated zone above a water table, pore spaces in a soil and rock contain ___.
Both air and water.
What type of aquifer is bounded above and below by layers of low permeability?
If the amount of discharge from an aquifer exceeds the amount of its recharge, the water table ____.
Will drop.
Karst topography forms in regions underlain by _____.
Which of the following statements about the water table is true?
The water table has the same general shape as the topography.
Mechanical weathering ___.
Reduces solid rock to small fragments without altering the chemical composition of rocks and minerals.
Weathering is the decomposition and disintegration of rocks and minerals at the Earth's surface by ___.
Both mechanical and chemical processes.
Wind, flowing water, glaciers, and gravity are ___.
Agents of erosion.
In soils, leached ions and clay frequently accumulate in the ___.
B horizon.
During ___ water dissolves a mineral to form a solution.
Rust is an example of ___.
Which of the following forces is the dominant cause of mass movement?
During ___, a coherent block of material fractures and moves downslope.
The ___ is the maximum slope or steepness at which to lose material remains stable.
Angle of repose
Piles of talus found at the base of cliffs in high alpine area are likely the result of ___.
Frost wedging.
Near the base of a glacier the ice is ___.
Relatively plastic and often warm enough so that free water may flow along bedrock.
Crevasses form in ___.
The upper brittle 50 meters of a glacier.
The higher elevation portion of a glacier where more snow accumulates in winter than melts in summer is called ___.
The zone of accumulation.
Imagine that a long-lasting glacier melted and a stream replaced the ice in the valley floor. After many years the valley shape could be best described as a ___.
Valley that looks like a V cut into the bottom of a U.
In a glacial terrain, a horseshoe-shaped depression beneath a steep cliff is a ___.
In glacial terrain, sharp ridge between two glacial valleys is an ___.
A glacier can move as fast as ___.
10 meters per day.
When glaciers grow, global sea level ___.
A kettle lake formed when ___.
Melting glaciers left huge blocks of ice in glacial sediment.
Which one of the following applies to a valley glacier that lengthens over a period of many years?
Accumulation exceeds wastage.
During the most recent ice age, glaciers covered about ___ percent of Earth's land area.
What is a desert?
Any spot on the earth that receives less than 25 cm rain/year.
Where are most of the world's deserts found?
At +/- 30 degrees from the equator.
What is a bajada?
A broad, gently sloping depositional surface formed from merging alluvial fans.
What is a desert pavement?
A remnant surface caused by deflation.
Which is not a type of sand dune?
What is loess?
Wind deposited silt, often of glacial origins.
Death Valley is an example of a ___.
Rain-shadow desert.
An ephemeral stream ___.
Contains water only after rainfall events.