1. Aim: How can we describe erosion caused by running water, wind, and glaciers?

2. Wind Erosion
Sandblasting (abrasion) – occurs when winds blow sand or silt grains against rocks and other objects
Lower portions of rocks become more eroded
Creates rounded and frosted sediments

5. Glacier Erosion
Glacier – naturally created mass of ice and snow, moves under influence of gravity
Act like a “river of ice”
Creates parallel scratches and grooves in rock as it moves.

6. Direction of grooves shows direction of movement
Carves a U-shaped valley
Creates semi-rounded and scratched sediments

11. Running Water Erosion Most common erosion type
Includes rivers, streams, and waves
Greater velocity transports larger particles
Creates smooth and rounded sediments

13. ▲ indicates the fastest velocity
Top View of River
Cross Section of
River at dashed lines ▲ ▲ ▲
▲ indicates the fastest velocity
DELTA

16. Streams carve v-shaped valley’s
Three factor’s determine stream velocity:
Gradient – the steeper the slope, the faster the river
Discharge – the more water, the faster the river
Stream Channel Shape – wide rivers run slow, narrow rivers run fast

18. Diameter What is the minimum rate of flow at which
a stream of water can maintain the
transportation of sediments?
Diameter
Rate of Flow
6.4 cm
0.2 cm
1.0 cm
25.6 cm

19. Name each particle size according to page 6 of the ESRT:
Diameter
Particle Size Name
0.008 cm
0.5 cm cm
7.5 cm
36.2 cm
5.3 cm
0.003 cm

20. Erosion Caused by Gravity
Everything that goes up……
….must come DOWN
Mudslides, landslide, rockslides and rockfalls are examples of erosion caused by gravity.
AKA Mass movement