The Solid Earth - Chapter 4: Wind Deposits Flashcards
Two distinctive types of wind deposits
Blankets of silt that were in suspension
Mounds of sand from the bed load
This is a material that has been deposited by dust storms and includes windblown silt
Loess
When loess is breached by streams or road cuts it tends to maintain ____ cliffs and lack visible layers
vertical
The distribution of loess indicates that there are two primary sources for this sediment:
Glacial, deserts
When does wind release its load of sediment
Velocity falls and energy available diminishes
Sand begins to accumulate wherever an ____ across the path of the wind slows the movement of air
Obstruction
Winds commonly deposit sand in mounds or ridges called
dunes
True or false: a dune creates a stronger obstacle as it grows
True
Does the windward or leeward size of a dune have a steep slope?
Leeward
The leeward slope of the dune is called the ____ face
slip
The sloping layers formed in the direction of the wind on the slip face
cross beds
This type of dune is solitary and shaped like crescents with tips pointing downward
Barchan
Barchan dunes form where supplies of sand are limited and the surface is relatively __________ (3x)
flat, hard, lacking vegetation
This type of dune is formed where vegetation is sparse/absent and sand is plentiful and features a series of long ridges separated by troughs and oriented at right angles
Transverse
A common dune form that is between barchans and transverse which form scalloped rows of sand oriented with right angles to wind
Barchanoid