1.Previous
3.Next

the rocks forming the Carneddau originated largely during the Ordovician period between 485 and 444 Ma (million years ago). Principal among these are the mudstones and sandstones of the Arenig (478-470 Ma) to Caradoc age (459-449 Ma) Nant Ffrancon Subgroup and the tuffs etc. of the Caradoc age Llewelyn Volcanic Group.

1.Previous
3.Next