Erosion and Deposition

6th Grade Earth Science

October 2012

Who is a 1 and who is a 2?

Turn to your partner and share with them the following: What is your favorite book and why?

If you are closest to my favorite book you are a 1, etc.

My favorite book is …

What is Erosion?

Erosion is the movement of sediment by wind, ice,

water, or gravity.

What is Deposition?

The dropping of sediment out of the wind, water, ice, or gravity and

settling in a new place.

Gravity

Sediment falls

Gravity ErosionAngle of Repose is the steepest angle, or

slope at which a material will not slide down.

Gravity DepositionMass Movement

gravity moves material down a slope

1. Landslide - rock & soil quickly

a. Slump – rock & soil suddenly fall, big mass

2. Creep – slow, down movement of rock/ soil.

3. Mudflow - mud

4. Avalanche - snow

What type of mass movement is each picture?http://classes.colgate.edu/dkeller/geol101/massw/mass.htm

LANDSLIDE MUDFLOW

SLUMP CREEP

1 2

3 4

IceIce (glaciers) carry sediment.

Ice ErosionContinental Glaciers – covers continent.

Flattens / smoothes landKettle Lakes

Alpine Glacier – in the mountains. Land made rugged.

Horns – sharp pyramid shaped peaks

U-Shaped Valleys

Ice DepositionTills – unsorted, deposited rock material

Moraines – ridges along edge of glacier

Stratified Drift – layers of rock deposited based on size

Outwash plain – large area of drift

Which type of glacier or landform is represented in each picture?www.uwsp.edu/.../lecture_glacial_processes.html

1 2

3 4

Continental Glacier Alpine Glacier

Kettle U Shaped Valley

2

3

4

1

What did glaciers create in each picture?

Outwash PlainSoutheast, Alaska

MoraineThompson Glacier,

Canadian Arctic

1 2

Wind

Wind blows sediment after it is weathered.

Wind Deposition Sand Dunes – mounds of wind deposited

sand. Move in direction of wind.

Loess – thick deposits of fine-grained, wind blown sediment

http://www.nwlg.org/pages/resources/geog/hydro_cycle/dunes/stop7b.htm

Water

Water (rivers, oceans, rain, etc.) washes sediment after being

weathered

Water Erosion Sea Cliffs – rock wears away

Sea Caves – hole in rock created by waves near cliff

Sea Arches – waves cut hole completely through rock in a sea cave

Sea Stacks – offshore column of rock once connected to the mainland

What did water erosion create in each of these pictures?

SEA CAVE

SEA STACKS

12

4 4 6

1 2

5

53 SEA ARCH

SEA CLIFFS

1

2

3

4

Water Deposition Deltas – slow river current drops sediment in fan-shaped

pattern at end of river

Sand Bars – offshore deposit of sand, gravel, or shell material

Alluvial Fans

Beaches – deposited sand

What did water create in each of these pictures?

DELTA SANDBAR

ALLUVIAL FAN

http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21604

1

2

4 4 6

1 2

4

53

BEACH