weathering the process of breaking down of rocks into smaller and smaller pieces of rock. these...

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WeatheringThe process of breaking down of rocks into smaller and smaller pieces of rock. These

small pieces are known as sediment. Sediment breaks down further and becomes

soil.

YehliuTaiwan-HoneycombWeathering180px-GeologicalExfoliationOfGraniteRock

Mechanical/ Physical Weathering

Chemical Weathering

Types of Weathering

Ice Wedging- Water in the cracks of rocks freeze

Abrasion- Particles of sand are carried by the wind and water

Plant Action – roots from plants grow in the cracks of rocks

Release pressure – when pressure is removed from rocks

Types of Mechanical Weathering

Chemical Weathering

The process in which the chemical makeup of a rock is changed by a chemical reaction.

http://en.wikipedia.org/wiki/Weathering#Chemical_weathering

Types of Chemical Weathering

Oxidation – a chemical change that occurs when oxygen and iron form.

Acids – natural acids break down rock.

http://en.wikipedia.org/wiki/Stalagmite

ErosionErosion takes rocks and other particles from

one location and puts them in another.

Weathering is breaking up rocks erosion is carrying them away.

The Agents of Erosion

WindWaterGlaciersGravity / Mass Movement

Wind ErosionWind can carry sand, silt, and clay from one place and deposit it in another.

This type of erosion is most frequent in dry areas with little or no vegetation.

Wind Erosion

http://upload.wikimedia.org/wikipedia/en/1/15/Mesquite_Sand_Dunes.JPG

Water Erosion

The most important agent of erosion is running water.

Water runs down hill and form a gully by taking away sediment.

Water continues to flow in the gully and eventually forming a valley.

Water can cause erosion of the shore line can be from waves in the ocean.

Water Erosion

http://en.wikipedia.org/wiki/Image:Gully_ElPasoCounty_CO_USA.jpg

Water Erosion

http://en.wikipedia.org/wiki/Image:Wavecut_platform_southerndown_pano.jpg

Glaciers Erosion

Glacier Erosion is sometimes referred to as Ice Erosion

Glaciers move slowly across land picking up large rocks and even larger boulders.

Glaciers can cause deep valleys to form as they move across the land.

Glaciers Erosion

http://en.wikipedia.org/wiki/Image:Glacier_mouth.jpg

Gravity/Mass Movement Erosion

Gravity is the force behind Water and Glacier Erosion

Gravity alone can cause Erosion

Gravity/Mass Movement Erosion

http://en.wikipedia.org/wiki/Erosion#Gravity_erosion

Slump CreepRockfallsRockslidesMudflowsLandslides

Types of Gravity/Mass Movement Erosion

Slump

http://geology.about.com/library/bl/images/blslump.htm

http://geology.about.com/library/bl/images/blslump.htm

A slump occurs when a mass of land slips and moves down a slope.

A slump occurs when the slope becomes too steep and the material under it can not support the ground above it.

Creep

Sediment slowly moves down hill.

Leaning trees and fence post are clues that creeping is occurring

Rockfalls

Occur when parts of a rock break off a tumble through the air.

http://www.seismo.ethz.ch/hazard/risk/PaleoSeis/rockfalls2.htm

Rockslides

http://www.grisda.org/origins/11090.htm

Large and small rock slide down a slope.

Mudflows

http://en.wikipedia.org/wiki/Image:Mudflow_mailboxes.jpg

Happen after heavy rains.More likely to occur when there is a lack of vegetation.Gravity pulls on the heavy water saturated sediment and causes it to flow down hill.

Landslides

http://www.signonsandiego.com/news/state/20050601-1811-wst-lagunalandslide.html

A movement of land down a slope.

Deposition

http://education.usgs.gov/lessons/schoolyard/RockSedimentary.html

Process by which sediments, soil and rocks are added to a landform or land mass (the end of erosion).

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