Palaeontological evidence for the age of some supposedly Precambrian rocks in Anglesey, North Wales

Abstract

The supposed worm burrows from the South Stack Group have been interpreted as dewatering structures. The stromatolites from the melange are identified as the Vendian–Cambrian form Georginia , and microfossils from the Lianddwyn Spilitic Group give a Lower Cambrian age for the Gwna Group.