Download Wind Erosion

Leveling Forces: Wind, waves and
gravity
http://tophdimgs.com/data_images/wallpaper
s/33/439253-sandstorm.jpg
Main Agents of Erosion and Deposition:
Wind Erosion: carries small particles, such as
sand, and these act like sand paper.
a. causes the rocks to have a pitted or
frosted appearance, as if they’ve been
sandblasted.
b. leaves the particles sorted by size, and
rarely carries particles larger than small
pebbles.
c. Contributes to the creation of strange
shapes, such as hoodoos and dunes
d. dunes show direction of wind movement,
with a gentle slope windward and a sharp
slope leeward.
http://www.americansouthwest.net/arizona/bl
ue-canyon/blue24_l.html
Jean McMahon
e. Wind erosion is the most important agent of
erosion in areas with arid/dry climates, and
flat terrain.
f. Loess is an accumulation of wind
blown sediment of very fine, clay
materials. Fine glacial sediments blew
across our country and much built up in
the southern states and plains.
2. Waves: carry sand and smaller particles to,
from and along the shore/beach.
ocean waves are powered by wind across the
water. Waves transfer energy.
TASA beach slide 1-11
The speed of waves depends on the
Strength of the wind
Distance over which the wind blows (fetch)
Length of time the wind blows
https://www.surfholidays.com/blog/What-Causes-the-Perfect-Wave
http://www.seafriends.org.nz/oceano/waves.htm
Waves grow taller when the depth of the wave is ½
the wavelength. The energy changes from a
horizontal to vertical position and gravity pulls the
‘breaker’ down.
There is increasing friction between the ‘trough’ of
the wave and the sand, slowing the bottom of the
wave, while more energy is given to the ‘top’ or
crest.
Water waves are primarily transverse waves, in
which particles move up and down while the
wave travels in a horizontal direction.
Longshore Currents (drift) occur due to the
combined actions of the refracted incoming wave
and the straight-moving outgoing undertow. The
net effect of these motions is to carry the
sediments down the beach, parallelto the beach
as pushed by wind.
TASA longshore slides 12-on
Jetties, groins, breakers, and other human
obstructions are designed to alter the longshore
current and keep the sand in one area. This can
have devastating effects further down the beach.
3. GRAVITY: rocks fall and are deposited at the
base of mountains.
• Sediments are never sorted by size or shape.
Talus slopes are formed from this material,
which can become breccia.
• TASA mass wasting
http://blogs.agu.org/landslideblog/2011/02/13/two-videos-the-aftermath-of-theremarkable-turkish-open-cast-mine-accident-and-a-cnn-hero/
http://www.latimes.com/local/california/lame-mud-climate-20151017-story.html
mass wasting: _large amounts of sediment move
under the influence of gravity.
soil creep: _slow motion of soil downhill due to
frost action and seasonal heating and cooling
landslide: _sudden movement of large amounts of
sediment on a steep slope.__
mudslide: _sudden movement of large amounts of
sediment mixed with water; often on steep
slopes._
http://team82science.blogspot.com/2014_09_01_archive.h
tml
http://www.mountainnature.com/geology/ero
sion.htm