Weathering, Erosion, and Deposition 1. Weathering Weathering is the breakdown of rock at the Earth’s surface. Some of these changes happen quickly and.

Weathering, Erosion, and Deposition

1. WeatheringWeathering is the breakdown of rock at the Earths surface.Some of these changes happen quickly and some happen slowly.

There are 2 Types:Mechanical and Chemical

2. Mechanical WeatheringMechanical Weathering the type of weathering where rock is broken down into smaller pieces without changing the chemical properties of the rock.This can be caused by freezing and thawing, release of pressure, growth of plants, and actions of animals (including humans).

Example: Water seeps into a crack in a rockWhen the water freezes, it expands

The force of the water expanding causes the rock to crack more.This is called ice wedging3. Freezing and Thawing

4. Plant GrowthRoots of trees and other plants enter into cracks of rocks.As the plants get bigger, so do the roots.The growing roots force the cracks further apart.

5. AbrasionAbrasion is the grinding away of rock by other rock particles.These particles scrape away at other rocks like sandpaper on wood as they rub or roll against the surface.

6. Chemical WeatheringChemical weathering is the processes of breaking down rock through chemical changes.5 things that cause chemical weathering: water, oxygen, carbon dioxide, living organisms (like lichens) and acid rain.Chemical weathering occurs more rapidly in warm wet climates.

Chemical Weathering causes the rock to experience a chemical change (changes its makeup)

Water dissolves rocks over timeOxygen causes oxidation (rusting)Acid rain reacts with marble and limestoneLiving organisms plant roots produce weak acids to dissolve rock around the roots, 7. Chemical Change

ACID RAINOXIDATION

CHECK- UP What type of weathering do each example cause?The roots of a plantAn animal scratchingOxygenWater freezingAcid rainWindWater

A. Chemical WeatheringB. Mechanical WeatheringC. Both types of weathering

What type of weathering???

What type of weathering???

What type of weathering???

What type of weathering???

What type of weathering???

What type of weathering???

What type of weathering???

8. ErosionWhen rock and soil are moved from one place to another by natural forces, this is called Erosion.The agents of Erosion areWater (rain water runoff, streams, rivers, groundwater, and waves)Ice (Glaciers)WindGravity ( landslides, mudslides, avalanches etc.)

9. SedimentThe material moved by erosion is sediment.Sediment is small, solid particles of rocks or organisms.

10. DepositionWhen the sediment being carried is dropped (or deposited) in a new area, it is called deposition.Depositions can create new landforms like beaches and sand dunes.

CHECK-UP Choose one of the following for each example:A.) ErosionB.)DepositionA river carrying sandDropping sediment in a new locationA glacier picking up a rock in its path.A beach is formed.How a sand dune is createdHow sediment is movedSand being carried by the wind in a sandstorm.