Shoreline Processes and Features

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Beach• A beach is the accumulation of sediment

found along the shore of a lake or ocean.• Beaches and shorelines are constantly

undergoing changes as the force of waves and currents act on them.

Wave Refraction• Wave refraction is the bending of waves and it

plays an important part in shoreline processes. It affects the distribution of energy along the shore.

Long shore Currents• The current that flows parallel to the shore

and moves large amounts of sediments along the shore is known as long shore currents.

Barrier Islands• Barrier islands are narrow sand bars parallel

to, but separated from, the coast.

• Waves along the shoreline are constantly eroding, transporting, and depositing sediment. Many types of shoreline features can result from this activity.

Forces Acting on the Shoreline

Wave Refraction• Because of refraction, wave energy is

concentrated against the sides and ends of headlands that project into the water, whereas wave action is weakened in bays.

Longshore transport• Turbulence allows

longshore currents to easily move the fine suspended sand and to roll larger sand and gravel particles along the bottom.

Erosional Features• Shoreline features that originate primarily from

the work of erosion are called erosional features. Sediment that is transported along the shore and deposited in areas where energy is low produce depositional features.

Protective Structures

• Groins, backwaters, and seawalls are some structures built to protect a coast from erosion or to prevent the movement of sand along a beach.

groin backwaters seawalls

Beach Nourishment• Beach nourishment in the addition of large

quantities of sand to the beach system.