high temperatures during the day heat up the rock which makes it expand
cool temperatures at night cause the rock to contract
this constant repeating of expanding and contracting causes stress and makes the layers of rock peel off- flaking. this happens by block disintegration (larger rocks break under constant stress) and granular disintegration (when the small minerals in the rock move due to them being different shades, the darker ones become hotter and stress more)
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crystal growth
high temperatures draw saline (salty) water to the surface, causing the water to evaporate, leaving the salt behind
the salt gets into cracks and salt crystals start to grow, this puts stress on the rocks and minerals leading to block and granular disintegration
along with insolation weathering this causes flaking
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frost thaw
this happens when there is large differences bwetween day and night temperatures
water trapped in rocks freezes over night and expands
at day the ice melts and the rocks contract again
this repeats causing the constant build up and let down of stress on the rocks until it breaks under this stress.
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Hydration
minerals in rocks expand when the absorb water, putting the surrounding rocks under more stress
this build up of stress causes the rocks to snap
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wind processes- creep
a bit like traction transport in rivers
this is when sand grains slide and roll across the surface
this happens due to small differences in pressure close to the surface creating lift
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wind processes- saltation
this is the bouncing of material across the ground at high wind speeds
when sand grains hit the surface, they cause more sand grains to start saltating
saltation is one of the key processes that form sandunes
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wind processes-suspension
small dust particles carried by wind in dust storms
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deflation
this is when the wind removes loose particles of sand and material from the surface.
this helps to form desert pavements, as it removes all small loose material, leaving only the large material behind.
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