. . "Hanging Knotts Tuff Member"@en . . . "Stratified bedrock. Occurs onshore. Deposited during the Caradoc Series (Ordovician Period) (458.2-449.75 Ma BP)."@en . "458.2"^^ . "HKT"@en . "Hanging Knotts Tuff Member"@en . "449.75"^^ . . "stable"@en . . .