Erosion and Deposition What is Erosion Erosion is

Erosion and Deposition

What is Erosion? Erosion is the movement of sediment by wind, ice (glaciers), water, or gravity.

What is Deposition? The dropping of sediment out of the wind, water, ice (glaciers), or gravity and settling in a new place. Creates new landforms.

Wind Erosion Wind blows sediment after it is weathered.

Wind Deposition ¢ Sand Dunes – mounds of wind deposited sand. Move 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 is the main agent of erosion.

Water Deposition Freshwater or Rivers ¢ ¢ ¢ Floodplain- an area along a river that forms from sediments deposited when the river overflows its bank Deltas – a fan-shaped mass of material deposited at the mouth of a river or the ocean Alluvial Fans – fan-shaped mass of material deposited by a stream with a steep incline occurs on land (freshwater)

Water Deposition (Ocean Waves) ¢ Sand Bars – offshore deposit of sand, gravel, or shell material (oceans) ¢ Barrier Island- is a long narrow island forms along the coastprotects coastal regions from waves and storms ¢ Beaches – deposited sand (ocean waves)

http: //www. schoolportal. co. uk/Group. Download. File. asp? file=21604 1 1 5 3 2 DELTA 4 2 44 ALLUVIAL FAN SANDBAR BEACH 6 5. Barrier Island 6. Flood Plain What did water create in each of these pictures?

Ice Erosion Ice (glaciers) carry and move metric tons of sediment.

Ice Deposition Till – unsorted, deposited rock material

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

Ice Deposition ¢ Moraine- is a ridge of sediment and rock left behind when a glacier melts

Gravity Erosion Sediment falls (sediments move down a slope)

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

Gravity Deposition Mass Movement gravity is a force that moves material down a slope 1. 2. 3. 4. Landslide - rock & soil move quickly down a slope (slump most common type of landslide) Creep – slow, downhill movement of rock/ soil. Mudflow – mud flows down a slope during heavy rains Avalanche – snow moves quickly down a slope

LANDSLIDE MUDFLOW 2 1 What type of mass movement is each picture? http: //classes. colgate. edu/dkeller/geol 101/massw/mass. htm CREEP SLUMP 3 4

Erosion and Deposition Exit Ticket 1. List one agent / cause of Erosion and one way it changes the Earth. 2. List a second agent / cause of erosion and one way it changes the Earth.