What is the difference between deflation and abrasion? Pick a
type of wind erosion and explain it.
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Saltation Deflation Abrasion
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Saltation: it is the skipping and bouncing movement of
sand-sized particles in the direction the wind is blowing. Moving
sand particles knock into each other, making other grains bounce
and roll. Areas that get strong winds experience saltation.
Slide 6
Slide 7
Abrasion is the grinding and wearing away of rock surfaces
through the mechanical action of other rock or sand particles. This
happens mostly in places that have strong winds, soft rocks, or
loose sands. Abrasion helps smooth out and shape rocks, like the
one shown.
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Loess Dunes The Movement of Dunes
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Loess- very fine sediments deposited by the wind Areas where
loess is present U.S. Midwest Eastern edge of Mississippi Valley
Eastern Oregon and Washington
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Dunes: a mound of wind-deposited sand that keeps its shape even
though it moves When the wind hits an obstacle, it slows and drops
the heavier material it was holding beforehand. As there is more
material building up, it is completely covered, forming a mound.
Dunes move in the direction of stronger winds but still keep their
shape. Dunes have a steep side, called a slip face, and a gently
sloped side usually facing the wind. Sand moves over the peak of
the dune from the gently sloped side and thus forms a steep
side.
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Move in the direction of winds Different wind conditions
produce various shapes and sizes Has 1 sloped side and 1 steep
sloped side Steep side=slip face Gently sloped side faces wind Wind
constantly transports material up gently sloped side Sand moves
over the peak of the dune, slides down slip face, creating steep
slope
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1q)What is the difference between deflation and abrasion? 1a)
The difference between abrasion and deflation is that abrasion
deals with the grinding and wearing away of rock surfaces, while
deflation deals with the blowing away of dry soil particles.
2q)Pick a type of wind erosion and explain it. 2a) Example:
Saltation is the movement of sand by short jumps and bounces that
is caused by wind or water.