Aeolian Environment

Question 1

a. Less than 250mm/yr precipitation

b. between 250 and 500mm/yr

Answer 1

a. Desert (Arid)

b. Steppe (Semi-Arid)

Question 2

(a) -Regions near 30° N & S latitude air sinks
(subtropical highs)
-Produce clear skies, sunshine, and ongoing
drought

(b) Give one example

Answer 2

Low Lattitude Desert

Simpson Desert

Question 3

(a) -Located in the deep interiors of continents
- Precipitation only 10-20 cm/yr

(b) Give one example

Answer 3

Mid Lattitude Desert

Gobi Desert

Question 4

are formed because tall mountain ranges prevent moisture-rich clouds from reaching areas on the lee, or protected side, of the range. As air rises over the mountain, water is precipitated and the air loses its moisture content.

Answer 4

Rainshadow Desert

Question 5

• Mean summer temperatures of -1.5 to 2° C
• Mean winter temperatures of -32 to -23° C

(b) Give one example

Answer 5

Polar Desert

Antarctic Desert

Question 6

is an area where sand has accumulated as a result of

aeolian processes.

Answer 6

Erg

Question 7

is blowing out and scattering of rock particles by

wind.

Answer 7

Deflation

Question 8

are sandy depressions in a sand dune ecosystem

(psammosere) caused by the removal of sediments by wind

Answer 8

Blowouts

Question 9

is the mechanical scraping of a rock surface, by

friction between rocks and moving particles

Answer 9

Abrasion

Question 10

Long exposure of rock surface in the oxidizing conditions of a desert also results of a dark, surface patina of iron and manganese oxides

Answer 10

Desert Varnish

Question 11

impact of saltating grains to have a frosted patina, like the frosting of glass windows

Answer 11

Grain Surface Frosting

Question 12

the selective removal of finer grains from the sediment in a flow, but is more effective in the lower density and viscosity medium of air

Answer 12

Winnowing Effect

Question 13

consisting of gravel-sized particles that are too large to be transported by the wind

Answer 13

Lag Deposits

Question 14

are dust that accumulate far from their source

Answer 14

Loess

Question 15

a hill or ridge of wind-deposited sand. Ranges from

3m to 600m in wavelength and are between 10cm and 100m high.

Answer 15

Dunes

Question 16

lunate structures with arcuate slips faces forming cross-bedding

Answer 16

Barchan Dunes

Question 17

straight-crested forms aligned perpendicular to the prevailing wind direction

Answer 17

Transverse Dunes

Question 18

a variety of dune intermediate between barchan and transverse dunes;these dunes form scalloped rows of sand perpendicular to the wind

Answer 18

Barchanoid Dunes

Question 19

characterized by cross-bedding reflecting avalanching down on both sides of the dune and oriented in different directions

Answer 19

Longitudinal Dunes

Question 20

– slip faces in many orientations and hence crossbedding directions are variable

Answer 20

Star Dunes

Question 21

initially originate as blowouts and the dune forms as the head of the dune at the downwind edge of
the blowout

Answer 21

Parabolic Dunes

Question 22

wind eroded (sand blasted) surfaces. With
changing direction of dominant winds, different facets
merge along sharp ridges to transform rounded stones to angular \_\_\_\_\_\_\_\_\_

Answer 22

Ventifacts

Question 23

are larger hill-sized features sculpted by the

wind. It is composed of cohesive silts and clays, sandstone, or limestone

Answer 23

Yardang

Question 24

An isolated mountain remnant characteristic of

the late stage of erosion in a mountainous region

Answer 24

Inselberg

Question 25

a broad, flat-topped area elevated above the surrounding land and bounded, at least in part, by cliffs.

Answer 25

Plateau

Question 26

a broad, flat-topped hill bounded by cliffs and capped with a resistant rock layer

Answer 26

Mesa

Question 27

a narrow hill of resistant rock with a flat top and very steep sides

Answer 27

Butte

Question 28

is determined by the amount of water that is charging the water-bearing strata

Answer 28

Water Table

Question 29

– sand dunes built up by aeolian action that from

adjacent to beaches in any climatic setting

Answer 29

Beach Dunes

Question 30

Wind blowing over the outwash plain can pick up sand

and redeposit it locally, such as the side of a valley.

Answer 30

Periglacial Deposit