Conglomerate at Gravel Bay: close-up view 1

Freshwater West, Gravel Bay and East Pickard Bay

Close-up view of a conglomerate in the Freshwater East Formation (note name) at Gravel Bay, situated at the northern end of the large Freshwater West bay in south Pembrokeshire. The lens cap is 72 mm in diameter.

The Freshwater East Formation marks the beginning of 'Old Red Sandstone' type of sediments, formerly believed to be at the base of the Devonian, but now assigned to the uppermost Silurian. The pebbles and cobbles in the conglomerates mostly consist of white vein quartz and quartzite, grey sandstones and darker sitstones. These were depositied in an alluvial fan settting on a shallow floodplain in increasingly arid conditions.