Definition: one or more beach ridges above the level of high tides formed of boulders deposited during storms.

Fine examples of boulder beaches occur in bays around the Caithness coast. The storm beaches showing typical size sorting, with smaller shingle at the base of the beach. This material is rounded, reflecting the high frequency of attrition as waves move the stones back and forward. The coarsest material forms the beach crest and here 1 m diameter boulders are not uncommon. These blocks may be less rounded, partly because only the biggest storm waves reach this part of the beach but also because blocks are often quarried by waves from the rocky shore in front of the beach and immediately thrown inland. A cover of lichen on the beach crest, notably the grey Leconara sp., indicates that the uppermost part of the beach has not been reworked for many decades. Behind the crest may lie older blocks, partly embedded in turf, that mark where the largest historic storms have overtopped the beach ridges.

grey Leconara sp
Storm beach at Crosskirk

© Copyright David Bremner (https://www.geograph.org.uk/photo/7357374)

Main image: Storm beach at Crosskirk (Alamy stock image _FC58TP)

Share This Story, Choose Your Platform!