Portballintrae
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Climate exposure
This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.
Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.
Geology & landscape
Geological Period: Quaternary
Landscape processes: Coastal, Glacial
Description
Portballintrae Pleistocene The cliff at Portballintrae consists of a series of sediments and features indicating the pattern of sediment deposition and fluctuations in the relative level of land and sea. They date from the latter stages of ice sheet retreat, some 17,000 years ago. The sequence is unique in north-west Britain. Nationally it is important because of the type of deposits present and the questions they raise about ice sheet reconstruction and its relationship to the recovery of land height following the removal of this ice. Additional issues raised by the site relate to the scale, timing and pattern of land and seabed deformation and rates of environmental change during this deglacial phase. Three major sediment series have been recognised. The lowest beds are typical of shallow tidewater resedimentation around unstable ice 'aprons' which accumulate near ice sheet margins. The overlying sands and muds contain a wide range of structures described from shallow, wave influenced, marine environments, some of which have not previously been described from ice related sequences in the United Kingdom. Foraminifera, a microscopic marine animal, are present in the muds and mainly belong to two species, Elphidium clavatum and Cassidulina obtusa. These species are typical today of cold water environments. Finally, development of the overlying gravels and sands occurred as lower beach deposits. https://www.daera-ni.gov.uk/publications/portballintrae-assi