Beach Characteristics Flashcards
(8 cards)
Define beaches
The point where the land meets the sea
Represents accumulation of sediment deposited between low spring tides and highest point reached by atom waves.
Sand/ shingle.
Sand beaches
More gentle gradient below 5 degrees.
Small particle size means the same becomes compact when wet and allows very little percolation.
Most swash therefore runs back as backwash - little energy lost to friction and material carried down beach
What features form on sand beaches ?
Ridges / runnels at low water mark.
They run parallel to shoreline and are broken by series of channel that drain water off the beach.
Shingle beach
Whole / upper part of beach.
Larger particles size = steeper gradient around 10-20 degrees
Water rapidly percolates though shingle so backwash is limited in transporting material back down beach.
This ^^ with the uneven surface means little erosion
Storm beach
Present at back of beach.
Strong wash above usual spring high tide
Biggest boulders by largest waves
Create ridges called berms - built by constructive waves.
Cusps
Semi circular depression which form when waves break directly onto beach and swash and backwash are strong.
Ripples
Below cusps
Wave / tidal action
Same 6 was characteristics on a beach ?
Ridges
Runnels
Storm beach
Berms
Cusps
Ripples
