Deserts Review-Mleziva

Deserts Review-Mleziva

1. Feature X in the photograph is being shaped by
A. saltation. B. abrasion. C. deflation. D. corrosion. Explanation

The feature is in a desert climate where cap rock is protecting softer rock materials underneath it. As the wind blows sand particles against this feature, further erosion occurs. Erosion of bedrock caused by rock particles that are carried by water, waves, wind, or glacial ice is known as abrasion (B) which is also known as corrasion.

Saltation (A) is a method of erosional transport in a river whereby rocks are rolled along the bed.

Deflation (C) is a gradual lowering of the desert floor due to wind erosion.

Corrosion (D) is the dissolving of soluble minerals by water in streams or waves; common in humid areas underlain by limestone rocks.

2. Features associated with a desert landscape are
A. arches and stacks. B. playas and levees. C. barchans and wadis.
D. salt flats and moraines.
Explanation

Arches and stacks (A) are coastal landform features.

Playas (i.e. salty lakes on the edges of alluvial fans) are desert features but levees (B) are river features so this option is eliminated.

Salt flats are desert features but moraines (D) are glacier features.

Barchans / Barkhans (i.e. crescent shaped sand dunes) and wadis (i.e. wide, dry ditches formed after rainstorm water evaporates) (C) are indeed both desert features.

3. A crescent-shaped sand dune is a
A. reg. B. wadi. C. playa. D. barchan.
Explanation
Reg (A) is an extensive desert lowland covered by pebbles and gravel.

A wadi (B) is a wide, dry ditch in the desert.

A playa is a salty lake (C) on the edge of an alluvial fan in a desert.

A crescent-shaped dune is indeed a barchan (D).

4. Barchans result from the interaction between the
A. lithosphere and the biosphere. B. biosphere and the hydrosphere.
C. atmosphere and the lithosphere. D. atmosphere and the hydrosphere. ExplanationBarchans are crescent-shaped sand dunes formed due to wind erosion and deposition. Wind is part of the atmosphere. Sand particles come from the lithosphere. Therefore, the answer is C.

5. Which process is responsible for shaping the boulder in the diagram above?
A. traction B. abrasion C. corrosion D. hydration Explanation

In the picture, wind blown sand particles are helping to erode the boulder. Erosion of bedrock caused by rock particles that are carried by water, waves, wind, or glacial ice is known as abrasion or corrasion (B).

Traction (A) or saltation is the movement of rock fragments by bouncing or hopping along the earth's surface by running water or wind.

Corrosion (C) is the dissolving of soluble minerals by water in streams or waves; common in humid areas underlain by limestone rocks.

Hydration (D) is the process of combining chemically with water.

6. The process illustrated in the diagram above is
A. deflation. B. corrosion. C. hydration. D. exfoliation. Explanation

The removal of sand due to wind erosion results in a lowering of the desert floor. This is known as deflation (A).