Erosion and Deposition 6 th Grade Earth Science

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.

Wind Erosion Wind blows sediment after it is weathered.

Wind Deposition Sand Dunes – mounds of sand deposited by wind. Moves in direction of wind.

Wind Deposition Loess – very fertile sediments of Quartz, Feldspar, Mica, and clay deposited by the wind

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

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 – fan-shaped mass of material deposited by a stream with a steep incline Beaches – deposited sand

What did water create in each of these pictures? DELTA SANDBAR ALLUVIAL FAN portal.co.uk/GroupDownloadFile.asp?file= BEACH

Ice Erosion Ice (glaciers) carry sediment.

Ice Deposition Tills – unsorted, deposited rock material

Ice Deposition Stratified Drift – layers of rock deposited based on size

Gravity Erosion Sediment falls

Gravity Erosion Angle of Repose is the steepest angle, or slope at which a material will not slide down.

Gravity Deposition Mass Movement gravity moves material down a slope 1. Landslide - rock & soil move quickly 2. Creep – slow, downward movement of rock/ soil. 3. Mudflow – mud movement 4. Avalanche – snow movement

What type of mass movement is each picture? LANDSLIDEMUDFLOW AVALANCHE CREEP