Wind Erosion

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Wind Erosion . Erosion. Mechanical weathering breaks rocks apart, erosion moves the broken pieces. Water Wind Ice. Sediment types. Sand = larger Dust (silt and clay)= medium Silt= small Clay=small. Wind erosion . Saltation Moves sediment by a series of jumps and bounces. - PowerPoint PPT Presentation

Text of Wind Erosion

Wind Erosion

Wind Erosion ErosionMechanical weathering breaks rocks apart, erosion moves the broken pieces.WaterWindIce

Sediment typesSand = larger

Silt= small

Clay=smallvery small

Dust (silt and clay)= medium

Wind erosion Sand is mostly transported bySaltation Moves sediment by a series of jumps and bounces

Wind erosionSilt is mostly transported byDeflation: winds blow sediment into air *dust storms

Why only sand and silt

Which Climates produce the most deflation?

desertis a barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground.Farmers

Everything is going to end up somewhere!

Sand dune formationa dune is a hill of sand built by either wind or water flow.

Formation Wind blows sandWind is slowed by some type of barrierAccumulation of sand can now occurMore sand is added buries original barrier * Limited by angle of repose 30- 40 degrees

Loess deposits predominantly silt-sized sediment, which is formed by the accumulation of wind-blown dust.

FormationWind carries dust and siltSilt is deposited in thin layersThick layers form from this accumulation *Loess often stands in either steep or vertical faces. loess will often stand in banks for many years without slumping. (unlike sand dunes!)

Wave erosion

ClickerThe fine-grained, sediment that is soft, easily eroded, and deposited by the wind in steep cliffs is called:

LoessSand duneDesert pavementDust stormsTimerTimes up!

Wave formation

usually result from the wind blowing over a vast enough stretch of fluid surface.

wind or some force causes up and down motion of water

Transfers energyBreakers Some waves undergo a phenomenon called "breaking". A breaking wave is one whose base can no longer support its top, causing it to collapse.

Wave hits the bottom of the shore or sand barCollides with another wave

Wave size3 Factors affect wind wave size:

Wind speed: wind must be moving faster than the wave crest for energy transfer

Wind duration: how long the wind blows

Fetch

FetchThe uninterrupted distance of open water over which the wind blows without significant change in direction.

Partner time

MichiganErieHuronSuperior Ontario Westerlies Long shore current Waves go at an angle to shoreline

Water moves along shore

Carries sediment with it

Shoreline erosion features

ABCDEFGMass movements Also known as mass wasting, is the process by which soil, sand, and rock move downslope largely under the force of gravity.

TriggersSaturation of water(heavy rain fall)Spring meltsEarthquakes/tectonicsWindHumans Mass movementsRockfall/slide:Sudden movement of rocks, normally in mountain regions

Landslide:Sudden movement of masses of loose rock and soil, down hill/slope.

Mudflow:It is a rapid movement of a large mass of mud formed from loose dirt and water.

Mass movementsLahar:Volcanic mud flow from ash

Slump:Slow moving block of soil movesDown hill

Creep:Very slow movement and very effective of all mass movements

ClickerWhat is the most common trigger for mass movements?

Water/precipitation WindEarthquakes Humans TimerTimes up!Mass movementsSolifluction:slow downslope movement of water-saturated sediment due to recurrent freezing and thawing of the ground, affected by gravity.

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Sheet1AnswerNumber, fraction, decimalA21B4D1Skipped1StudentAnswerLeah WilsonAAubrey MathewsAKatie TrostAEvan SutherlandBHoward CraneAJoseph CalhounAChristopher ReeberAJeffrey BuhlABrien DawsonAJohn HolmeBAnton MikolowskiBHadley ClemensAPierson ManikasDFrederick BergEdward StaceyBKathryn MollisonAAlexandra GormelyAKatiana KnuthAJack UznisAEmma RussellAJohn EcclestoneARobert WelsherAAmanda ChristianAMegan MichaelsAJay UlbrichACourtney MestdaghACourtney CalcaterraA

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