Erosion and DepositionErosion and Deposition

Mass MovementMass Movement

Goals:

1) Understand what processes wear down the Earth’s surface.

2) Distinguish between the different types of mass movement.

ErosionErosionThe process by

which natural forces move rocks and soil from one place to another.

On Earth water is the primary agent of erosion

DepositionDepositionOccurs where agents of

erosion lay down sediment (sand, soil, rocks etc.) to make new landforms

Erosion and Deposition work together to build up and wear down the land over and over again.

Mass MovementMass Movement

Gravity is the force that moves rock and other material downhill.

There are several types of mass movement – moving materials like dirt, rocks and sand down hill.

LandslidesLandslides

Are the most destructive kind of mass movement

Occurs when rock and soil move quickly down a steep slope

LandslidesLandslides

LandslidesLandslides

MudflowsMudflows

A rapid movement of a mixture of water, rock and soil.

Water may make up 60% of flow.

Often occur after heavy rains in dry regions

MudflowsMudflows

MudflowsMudflows

SlumpSlump

A mass of rocks and soil slip down hill together in one large piece.

Often looks like someone took a bottom piece out from under the slope

SlumpSlump

CreepCreep

Very slow downhill movement of rock and soil

Movement can create weird angles and tilt objects like telephone poles

CreepCreep

Mass MovementMass Movement

The downhill movement of eroded material.

Water and gravity are major factors in erosion

Question:Why would a landslide be more likely on

a steep slope than a gentle slope?