Exam 18: Deserts and Wind Action

A mesa is capped by sedimentary rocks while a butte is capped by a lava flow.

A _____ is a depression on the land surface caused by wind erosion which may have a pillar left at the center.

This area of the desert southwest is characterized by mostly flat-lying beds of sedimentary rock over 1,500 meters above sea level.

Most sand dunes are asymmetric in cross section with a gentle slope facing the wind and a steeper slope on the downwind side.

Rapid down cutting of desert stream channels produces narrow canyons with vertical walls and flat gravel-strewn floors.

A ______ is a narrow hill of resistant rock with a flat top and very steep sides found in some deserts.

A transverse dune is a relatively straight,elongated dune oriented parallel to wind direction.

Most dunes move only ____ per year.

Thin rocky soil and slow rates of creep make desert topography steep and angular.

A large dune type is the _______ (or seif)dune,which forms a ridge parallel to prevailing wind direction.

Loess deposits in the U.S.Midwest are derived from ____.

Desert stream channels called ____ are characterized by narrow canyons with vertical walls and flat,gravel-strewn floors.

The world's best-known deserts lie in a belt 10-15 degrees centered at latitude of 30 degree (North and South).

An area with desert conditions in the United States is ____.

The steep downwind face of a sand dune is called the ______.

How do deserts form in coastal tropical regions?

_______ is a thin surface layer of closely packed pebbles found in deserts.

This agent of erosion and deposition is most effective on fine sediment that is dry.

Which of the following would not be a control on desert development?

Because of their low rainfall,intermittent stream flow,and dry stream beds,desert lack ____.