. "477.1"^^ . "Greenstone And Spilite Volcanics"@en . "461.25"^^ . "Bedrock. Occurs onshore. Formed during the Arenig Series - to - Abereiddian Stage (Ordovician Period) (477.1-461.25 Ma BP)."@en . "HBHS"@en . "Greenstone And Spilite Volcanics"@en . . "stable"@en . . . .