"470.75"^^ . . . . . "Stratified bedrock. Occurs onshore. Deposited during the Fennian Stage (Ordovician Period) (470.75-468 Ma BP)."@en . "Cwm Gwaun Formation"@en . . . . "stable"@en . "468.0"^^ . "Cwm Gwaun Formation"@en . "CGW"@en .