Orkney and Caithness

The landscapes and landforms of OrkneyOrkney and CaithnessCaithness have been profoundly influenced by the varied lithology and structures of the Devonian sedimentary cover. During the NeogeneNeogene, an extensive planation surfacePlanation surfaces developed across CaithnessCaithness, with sandy weathering covers, which was subsequently uplifted and dislocated by fault movements. In the PleistocenePleistocene, ice flowed out of the Moray FirthMoray Firth, overdeepening the marine basin, and crossed northern CaithnessCaithness and OrkneyOrkney. The land surface was locally roughened and streamlined but in southwest CaithnessCaithness and on some hill summits during the most recent ice-sheet glaciation(s) the ice cover remained cold-based and non-erosive. TheLast ice sheet last ice sheetIce sheets left complex glacigenic depositsGlacigenic deposits and formed sequences of recessional moraines during its retreat from near the Atlantic shelf edge. The coast is predominantly rocky, with an outstanding assemblage of cliffs, caves, stacks, arches and shore platforms reactivated by rising postglacial sea levelsSea level. The severe wave-energy environment has produced remarkable examples of cliff-top storm deposits. In contrast, in sheltered, low wave-energy environments in the northern isles of OrkneyOrkney, glacigenic and biogenic sediments have been reworked into extensive beaches, tombolos and dune systems. The exceptional landscape of the Flow CountryFlow Country of CaithnessCaithness developed through the formation of extensive blanket bog during the HoloceneHolocene.