Looking like lots of pastel-coloured sugared almonds, these pebbles from Rhossili Bay reflect not only the immediate solid geology of the area but also the surface geology relating to former glaciation events.
The pale blue-grey smooth stones are Carboniferous Limestone which outcrops in the two headlands of the bay at Worms Head and Burry Holms. The pink and red relatively coarse-grained stones are derived from the Old Red Devonian Sandstone which forms the basis of Rhossili Down at the head of the bay. Other stones of all sorts, originally from places far away, have been delivered to the location as they melted out of the bottom of an ice sheet or glacier over 10,000 years ago.
Revision of a post first published 26 March 2009
COPYRIGHT JESSICA WINDER 2011
All Rights Reserved