The document discusses various shoreline processes driven by wave motion. It explains that waves form as energy moves through water, with water particles moving in a circular pattern. As waves approach shallow water, they break due to friction, piling up water that rushes onto the shore and moves sediment. Waves typically approach the shore at an angle and carry sediment along the coast in a zig-zag pattern through longshore transport. Breaking waves can also transport sediment diagonally inland during swash before the sediment moves seaward during backwash.

1. Photo by W. W. Little
Shoreline Processes

2. Wave Motion
Waves are formed as energy moves
through water. Water particles move
in a circular pattern, more or less
returning their point of origin once
the wave has passed.

3. Photo by W. W. Little

4. Breaking Waves
As waves approach shallow water, they hit bottom. Due to the resulting
friction, the upper part of the wave moves more rapidly than the lower
part. Water piles up and the wave breaks, causing water to rush onto
the shore. Sediment is moved both by wave base and by surf.

5. Photo by W. W. Little

6. Longshore Transport
Waves typically approach the shore at an angle. Upon breaking, their momentum
carries sediment onto the beach in the direction of the angle of encroachment until
wave energy is spent. Gravity then pulls the wave and sediment seaward,
perpendicular to the shoreline. This process carries sediment along the coast in a zig-
zag pattern.

7. Photo by W. W. Little
Surf/Swash
Breaking waves (surf) are capable of transporting large volumes of
sediment diagonally landward as part of the beach swash.

8. Photo by W. W. Little
Swash
(breaking
wave)
Backwash (return flow)
Backwash
Once wave energy has been expended as swash, water and sediment
move seaward, perpendicular to the shoreline, as backwash.

9. Photo by W. W. Little

10. Photo by W. W. Little

12. Beach Progradation
Beach progradation is a type of lateral accretion, as beach ridges build
basinward through long-shore transport.

14. Channels
Numerous small fluvial
channels flow to the swash
zone.

15. Rip Currents
Water piled against a shoreline by ocean
currents must return to sea. It does so by
flowing as a stream through breaking waves.

18. Cause of Tides
Passage of the Moon overhead
creates a gravitational bulge that
migrates with the Moon’s orbit.
An equal bulge is formed
concurrently on the opposite
side of the earth.

22. Transgressive vs. Regressive Shorelines
The types of depositional systems that dominate a shoreline differ
depending upon whether base-level is rising or falling.