Exam 10: Streams and Floods

Hydraulic action refers to the ability of flowing water to pick up and move rock and sediment.

Streams erode rock and sediment by ___.

A stream reaches its maximum velocity close to the shoreline.

Floods are described by ____, the average time between floods of a given size.

Flood control structures along the Mississippi River surrounding New Orleans are predominantly _____.

Stream discharge is one of the most important factors that controls stream velocity.

Certain features on the planet Mars resemble _____ on Earth.

_____ meanders are meanders that retain their sinuous pattern as they cut vertically downward below the level at which they originally formed.

A cutoff meander may become a crescent-shaped __.

On large alluvial fans, the _____ sediment is deposited near the mountains.

An alluvial fan is a fan- or cone-shaped pile of sediment that forms where a stream emerges from a narrow mountain canyon.

A _____ is a ridge of sediment built by sedimentation on the middle or banks of a stream channel.

Sheetwash is a thin layer of unchanneled water flowing downhill.

___ beds form the main body of a delta with angles of inclination up to 20 to 35 degrees in small sandy deltas.

___ is/are sudden localized floods of large volume and short duration, often triggered by heavy rainstorms.

Low stream velocity generally results in erosion and transportation of sediment.

A(n) __ is the body of sediment deposited at the mouth of a river when the river's velocity decreases.

In North America, the ___ separates streams that flow into the Pacific Ocean from those that flow into the Atlantic Ocean and Gulf of Mexico.

A stream's discharge is __.

_____ refers to sand grain movement in a series of short leaps or bounces off the bottom.