cliff-top storm deposits


sea level change

ayres or tombolos

Key sites

Ayre o Swinister

Stead of Culswick








Spiggie pollen site was located in the bog between the two lochs

Coastal deposition

Bay head bar and lagoon, Laxo Firth

Spits, bars and ayres are characteristic of the inner coast and voes of Shetland. The bars can be classified according to position as mouth, mid and bay head bars. If the bars grow to become a barrier across the firth then a lagoon is formed from which the sea is excluded except during storms. The lagoon fills with sediment and vegetation over time to leave a reed-covered bog. These features are typical of submerging coastlines. Each should hold a record of coastal change and storms, although pollen investigations at Aith Voe and Spiggie Loch failed to find evidence of sea level change.