Water-worn Limestone (WHC2) 31 – Weathering of Carboniferous Black Rock Limestone Sub Group layers on the Worms Head Causeway in Gower, South Wales, showing the wearing, smoothing, and shaping effects of a combination of erosion by mechanical abrasion (waves carrying stones), acid dissolution (rain water) and bio-erosion (damage caused by micro-organisms and marine invertebrates).
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