Beach Features Flashcards
List the order of the sections of a coastline (Littoral zone).
Backshore Foreshore (shoreline) Nearshore Offshore
What is a berm and how are they formed?
Small ridges that develop at the position of the mean high tide mark resulting from deposition at the top of the swash. Berms are generally created by smaller waves which have less energy so the material is smaller.
What is the littoral zone?
The littoral zone is the near shore area where sunlight penetrates all the way to the sediment and allows aquatic plants (macrophytes) to grow.
What is the backshore?
The backshore area of a beach extends from the limit of high water foam lines to dunes or extreme inland limit of the beach. It is only affected by waves during exceptional high tides or severe storms.
What is the foreshore?
The part of a shore between high- and low-water marks, or between the water and cultivated or developed land
What is the nearshore?
The zone extending seaward from the low water line well beyond the surf zone; it defines the area influenced by the nearshore or longshore currents. The nearshore zone extends somewhat further seawards than the littoral zone.
What is the offshore?
The offshore zone is defined as the zone off the nearshore zone.
What are beach cusps and how are they formed?
Cusps are crescent-shaped indentations that form on beaches of mixed sand and shingle. They are formed where there is a junction between sand and shingle. Once the curving shape is created, swash is concentrated in the small bay that forms in the centre of the cusp. This creates a stronger backwash that removes material down the beach.
What are ridges and runnels and how are they formed?
Ridges and runnels form parallel to the shore line in the foreshore zone. Ridges are areas of the foreshore that are raised above the adjacent shore which dips into a runnel. The runnels are disrupted by channels that help to drain the water down the beach. Ridge and runnel systems are formed due to the interaction of tides, currents, sediments and the beach topography. They only form on beaches with a shallow gradient. They form as a simple drainage route for tides. Water flows in and out via the runnel.
