Limestone pavements and Karst scenery
Anglesey’s Carboniferous limestone exposures may be small in global terms but they do illustrate limestone is weathered by groundwater solution. Such landscapes are known generally as Karst.
A special feature of karst scenery is the limestone pavement, flat bedding planes exposed by glacial erosion then subject to solution weathering along joints or other structural weaknesses. As these joints are widened by solution of the limestone, the bed takes on the appearance of a series of slabs [known as clints] separated by deep grooves [ known as grykes]….. similar to a roadside pavement or patio.
Biological interest in such features is very great in areas like the Burren in Ireland and the Yorkshire Dales where the grykes provide a sheltered habitat in an otherwise harsh, windswept upland landscape.
On Anglesey, coastal exposures were originally buried under glacial sediments which are now eroding and exposing the rock……one can trace the development of solution weathering from the most exposed area to that only recently uncovered … a pattern on well established grykes giving way to glacially smoothed surfaces with deep striations.