Erosion

Process by which soil and rock are removed from the Earth’s surface by natural processes and then transported and deposited in other locations. What is it?

Agents of Water Erosion Rainfall Coastal Floods Thawing Rivers and streams Glaciers Freezing Agents of Water Erosion

Raindrop creates a small crater, when drop rate is faster than infiltration, surface erosion occurs Rainfall

Continued water flow deepens water and also extends into hillside Wearing away of banks Melting and weakening of permafrost due to moving water, causes weakened banks to fall Rivers and Streams

Coastal Currents and waves pounding coastline Seawater can dissolve rocks Sediment being carried away, and not replaced Coastal

Glaciers Scrape the bed, which polishes and gouges underlying rocks Pieces of bedrock to crack off Freeze to bed, when glacier moves, moves the bed with it Glaciers

Floods Cause local erosion by taking up bedrock and forming pothole-type features

Water in cracks, freeze and expand, breaking rock into several pieces can lead to gravity erosion Morning thaws can drop rocks onto road Freezing and Thawing

Other Agents of Erosion Wind Gravity Exfoliation Other Agents of Erosion

Wind Arid or semi-arid regions Pick up or carry loose particles away Structures repeatedly struck by airborne particles Wind

Gravity Mass movement downward and outward movement of sediment Moves material from higher to lower elevations Occurring along slopes Can move at any speed Gravity

Rapidly heated by the Sun Expansion of rock, Rock contracts, Rock piece breaks off Mostly in deserts Exfoliation

Material is added to land mass Builds up layers of sediment Deposition