Weathering and Erosion

Weathering

• The breakdown do the rocks into smaller pieces, by water, plants, ice, and wind.

Weathering

WeatheringIs the process by which rocks are broken down into smaller pieces by external conditions.

Types of Weathering Ice or frost wedging - temperature change Abrasion - friction and impact Plant roots and burrowing of animals Humans – building houses, roads, dig

tunnels, or blast into rock

Ice or Frost Wedging

Ice or frost wedging is the freezing and thawing of water in cracks that causes rocks to bread apart or disintegrate in to smaller pieces.

The freezing and thawing cycle of water break the rocks into different size pieces and they are then deposits at the base of the mountain by gravity.

Falling rocks hitting other rock is also a form of abrasion and repeated impact.

Ice or Frost Wedging

When in the water in the ground freezes it can cause sidewalks and patios to lift up.

Plant Roots

A plant’s small roots wedge themselves inside small cracks in a rock. As the plant grows the larger roots make the crack bigger and bigger, causing the rock to break apart.

Abrasion: Friction and Repeated Impact

Moving water can smooth and round the edges of rocks.

Living Organisms

• Lichens that grow on rocks produce weak acids that chemically weather rock

Burrowing of animalsalso help break down rock

ErosionIs the movement of sediment

by wind, water, and glaciers and gravity.

Water Erosion

• Rivers, streams, and runoff

Water

• Water weathers rock by dissolving it

Ice Erosion

• Glaciers

Wind Erosion

Mass Movements of land caused by ground water.

Rock is Change by Weathering and

ErosionWeather

ing is the

process of

Breaking down

rock

ErosionIs the

process of

Movingrock