Weathering

23.2

Erosion / Weathering

Erosion

• The process that wears down and carries away rock and soil

• Ex. Grand Canyon• Destructive process that

shapes the Earth surface • Works through • Weathering – Gravity• Streams—Groundwater• Glaciers—Wind—Waves

WeatheringWeathering• The Process where

rocks are • chemicallychemically altered or• physicallyphysically broken

down into fragments

Mechanical Weathering

• Mechanical WeatheringMechanical Weathering = Physically breaking rocks

• Frost Wedging

–Water freezes into ice and expands breaking rock

• Abrasion

–Rocks scraping against each other

Mechanical Weathering

• Plant roots–Root grow into rock and

pry rock apart• Release of pressure

–Removing excess material allows for expansion of material allow rocks to crack

Chemical Weathering

•Chemical reactions break down the bonds holding

the rocks together,• causing them to fall apart,

• forming smaller and smaller pieces

Acid Rain