Erosion of Earth’s SurfaceErosion of Earth’s Surface

SWBAT identify agents of erosion; SWBAT identify agents of erosion; describe the effects of erosiondescribe the effects of erosion

Agents of ErosionAgents of Erosion

• Erosion– the wearing away and removal of rock or

sediment.

• List the 4 main agents of erosion.– Gravity– Ice– Water– Wind

GravityGravity

• Mass movement – when gravity alone causes rock or sediment

to move down a slope.

• What is the main force that causes all of these mass movements to happen?– Gravity

Mass MovementsMass Movements

• Creep– The process in which sediments move slowly

downhill.– This is common were freezing and thawing

occur

Mass MovementsMass Movements

• Slump– Occurs when a mass of rock or sediment

moves downhill, leaving a curved scar.– These are most common thick layers of loose

sediment.

Mass MovementsMass Movements

• Rock slides– Layers of rock break loose from slopes and

slide to the bottom.– They can reach speeds higher than 250 km/h.– Most commonly occur in mountainous areas.

Mass MovementsMass Movements

• Mudflows– A mass of wet sediment flows downhill over

the ground surface.– Happens where heavy rains or melting snow

and ice saturate sediments.– Can reach speeds of 160 km/h.

IceIce

• What are the two types of glaciers?– Valley glacier

• Glaciers that form in valleys in high, mountainous areas

– Continental glacier • Glaciers that cover broad continent-sized areas

• How do glaciers erode rock?– Ice can pull pieces of cracked rock out and

carry it along, scratching earth’s surface as it moves, creating grooves or striations.

WindWind

• Deflation – when wind blows across loose sediment like

silt and sand, it lifts and carries it.

• Abrasion – makes pits in rocks and produces smooth,

polished surfaces.

• Both deflation and abrasion are caused by what eroding agent?– Wind

WaterWater

• Runoff – water that flows over Earth’s surface.

• What are some landforms that can be created from erosion?– Canyons – Valleys– Hills– Sandbars– Deltas

Get your lab notebookGet your lab notebook

• Title: Can evidence of sheet erosion be seen in a farm field?

• With a partner read the applying science box on page 329.

• Complete number 1-3 under solving the problem in your lab notebooks.

With a partnerWith a partner

• Answer questions 1-5 on page 331.

• Be sure to answer in complete sentences, restating the question.

• Finish for homework