1. Waves
Section 9.5

2. Waves Waves form from wind that blows across the surface of the water
Particles of water move in a circular pattern but the wave moves forward

3. As a wave moves near land, the bottom drags and the wave slows down
As a wave moves near land, the bottom drags and the wave slows down. The water moves forward and provides the force that changes the shoreline

4. Erosion by waves Impact – waves hit rock and break them
Abrasion – waves carry sediment that wears
away other rock
Headland – a part of the shore that changes
the direction of waves

5. Landforms
Sea cave – where waves erode softer rock
at the base of land

6. Landforms Wave cut cliff – where rock collapses
because the base was hollowed out

7. Landforms
Sea arch – where waves erode softer rock under harder rock. If the arch collapses a sea stack could appear
Sea Arch Sea Stack

8. Deposits
Beaches – an area of wave washed
sediment along a coast

9. Deposits
Longshore Drift – waves, that hit the shore on an angle and run parallel to the shore, carry sediment down the beach

10. Deposits
Spit – a beach that projects out into the water as a result of a longshore current

11. Deposits
Sand Bar – long ridges of sand parallel to
the shore

12. Deposits
Barrier Beach – when waves pile sediment
up above sea level

13. Wind Erosion
Section 9.6

14. How Wind Causes Erosion
Wind is the weakest agent of erosion
It can be a powerful force in areas where there are few plants

15. How Wind Causes Erosion
Deflation – the process by which wind removes surface materials.
The stronger the wind, the larger the particle that can be moved

16. How Wind Causes Erosion
Abrasion – wind carried sand can polish rock (sand blasting) but causes little erosion.
Could have been caused
by weathering or water erosion

17. Wind Deposition When wind slows down, sediment is deposited
Sand dunes and loess deposits are formed by wind erosion and deposition

18. Sand Dunes Form when wind strikes an obstacle
Found on beaches and in deserts where sediment has built up

19. Sand Dunes

20. Loess Deposits Fine sediment deposited far from its source
Found in central part of U.S.
Helps to form fertile soil

21. Loess Deposits