Definition of shingle beaches and structures

There are many definitions of what constitutes a shingle structure, those given below are principally derived from their geomorphological development. They cover the types most frequently encountered in coastal locations in northwest Europe. Shingle beaches and structures are defined by the size range of the particles and are usually composed of "deposits of pebbles ranging in size from 2mm - 200mm in diameter" (Randall 1977a; Randall 1977b). It is a globally restricted coastal sediment type with few occurrences outside northwest Europe, Japan and New Zealand. Shingle shorelines and structures develop in areas of high wave energy. Their precise form is dependent on the wave direction, the incidence of storms and the availability of sediments.

Definition of shingle beaches

Shingle shorelines occur as fringing beaches where storm waves throw pebbles on the beach which are subject to periodic displacement or overtopping by high tides and storms. On some shorelines varying amounts of sand are interspersed in the pebble matrix and gradations to sandy shores may occur. Beaches are described as being "accumulations of sediment deposited by waves and currents in the shore zone" (Bird 1984). Shingle beaches are widely distributed round the coast of the UK, where they develop in high energy environments. In England and Wales it is estimated that 30% of the coastline is fringed by shingle. However most of this length consists of simple fringing beaches within the reach of storm waves, where the shingle remains mobile and vegetation is restricted to temporary and mobile strandline communities.

Definition of shingle structures

"Shingle structures are accumulations with a sequence of ridges, which become piled up against each other in parallel lines. The predominant particle size is the same as for shingle beaches. The difference relates to the frequency of displacement by storms. They range in size from small features with saline 'percolation ponds' to much larger structures where the older ridges become completely separated from the sea by new deposits thrown up during storms or on shorelines where relative sea level is falling." (Doody 2001)

References

Bird, E.C.F. 1984. Coasts: An Introduction to Coastal Geomophology. Third Edition. Basil Blackwell, Oxford, 320 pp.

Doody, J.P. 2001. Coastal Conservation and Management: an Ecological Perspective. Kluwer, Academic Publishers, Boston, USA, 306 pp. Conservation Biology Series, 13

Randall, R.E. 1977a. Shingle foreshore. In: The Coastline, ed.Barnes, R.S.K.John Wiley & Sons, Chichester, 49-61.

Randall, R.E. 1977b. Shingle formations. In: The Coastline, ed.Barnes, R.S.K.John Wiley & Sons, Chichester, 199-213.