Gwydir Bay
Also within
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
Description Geomorphological interest. Gwydir Bay is an important Pleistocene site for the most extensive and well exposed sections in northern Lleyn of till derived from southward moving Irish Sea ice. Massively bedded, pink/grey, shelly Irish Sea till is replaced northwards by well bedded, virtually horizontal sands and gravels. Both the till and gravels are thought to belong to the oldest known glacial advance in the area, the Trevor Advance, and clearly demonstrate a major incursion of Irish Sea ice on to the north Lleyn Coast. The precise timing of this glacial event has not yet been established beyond doubt but amino acid dates may clarify the chronology. Gwydir Bay is an important reference site for the Trevor till.