Erosion and Mass Erosion and Mass MovementsMovements

RRB page 161-162RRB page 161-162

ErosionErosion Erosion: The carrying of sediment by wind, Erosion: The carrying of sediment by wind,

water, ice and other agentswater, ice and other agents Erosion is the process by which sediments Erosion is the process by which sediments

are obtained and transportedare obtained and transported Erosion is also the wearing away and Erosion is also the wearing away and

lowering of Earth’s land and surface lowering of Earth’s land and surface featuresfeatures

DO NOT WRITE: The sun plays an important DO NOT WRITE: The sun plays an important part in erosion. The sun drives the water part in erosion. The sun drives the water cycle, and therefore, precipitation for cycle, and therefore, precipitation for running water and glaciers. Insolation also running water and glaciers. Insolation also ”fuels” wind patterns that create ocean ”fuels” wind patterns that create ocean currents and wavescurrents and waves

Triggers of Mass Movements

Mass MovementsMass Movements

Among the factors that commonly trigger mass movements are saturation of surface materials with water, oversteepening of slopes, removal of vegetation, and earthquakes.

Types of Mass Movements

Mass MovementsMass Movements

Geologists classify mass movements based on the kind of material that moves, how it moves, and the speed of movement.

Rockfalls

Types of Mass Movements

Mass MovementsMass Movements

• Speed: 1 mm/ day to 1 km/hr

Debris Flow

Heavy Rains Can Trigger Heavy Rains Can Trigger SlumpsSlumps

Types of Mass Movements

Mass MovementsMass Movements

•Mudflows

Mudflows

Flows• Flows are mass movements of material

containing a large amount of water.

Types of Mass Movements

Mass MovementsMass Movements

Creep

*Creep can cause: Cracked roads, leaning utility poles, and bent trees