processes

inherited elements

Key sites

Muckle Head

Shore platform near Outer Urrigar on Eynhallow. Platform erosion by block removal  is facilitated by the gentle dip of the sandstone to seawards.

Other shore platforms

Caithness

East Lothian

 

Shore platforms

Significance: a rock shelf fringing the coastline between the low and high water marks



Shore platforms are an important element of the Orkney coastline. In the northern isles, platforms are developed along many kilometres of coast and virtually encircle some of the smaller islands, such as North Ronaldsay. Platforms occur even in sheltered locations, such as the shores of Scapa Flow. The platforms vary in size, with the Holm of Aikerness covering almost 0.5 km2. No consistent variation in width with orientation is obvious, although platforms are less developed on west-facing cliffed shorelines. On west Hoy, the intertidal shore platform is 40-70 m wide, with a partial cover of fallen boulders (May and Hansom, 2003).

On the exposed outer coasts of Orkney shore platform development is probably as rapid as anywhere in the world. Large scars from recent block removal are widespread. After storms, the platform surface carries many impact marks where blocks have been moved across its surface. The rear of the platform is also scoured whenever beach debris is dragged across it.