Exam 18: Deserts and Wind Action

The Basin and Range province is characterized by rugged mountain ranges bounded by faults.

Dunes are not just desert features,they are commonly found near ____.

Rock debris picked up in flash floods is deposited at the base of mountains in ____.

A pediment is an erosional surface underlain by solid rock,while a bajada is depositional and is underlain by sediment.

A butte is a narrow valley with a narrow bottom and flat sides.

Sand grains found in dunes are commonly _______.

Deflation continues to deepen a blowout until it reaches ______.

Where sand supply is limited a barchan dune generally develops.

____ is a hard shiny coating of dark iron and manganese oxides and clay minerals that form on rock surfaces in arid environments.

In passing over a dune,wind scours sand from the downwind or slip face.

The "horns" in a _______ dune point in a downwind direction.

The high runoff following sporadic desert downpours can create sudden local floods called ______.

Dune sand throughout the world is composed of the stable mineral quartz.

Some of the world's deserts are the result of the rain shadow effect of mountain ranges.

The Colorado Plateau is marked by peculiar,step-like bends in rock layers called ____.

Loess is a deposit of wind-blown silt primarily composed of unweathered angular grains of quartz and feldspar.

The expansion of deserts into once populated areas is known as ___.

Not all deserts are hot.Descending air near the North and South poles creates ____ deserts.

Dune types are influenced by wind velocity.

A desert is any region which has a dry or arid climate with a low rainfall of less than 25 cm per year.