"449.75"^^ . "stable"@en . . . "Basaltic pillow lava, with associated bedded chert."@en . "Craighead Volcanic Formation"@en . . . "Basalt lava with subsidiary chert. Stratified bedrock. Occurs onshore. Deposited during the Abereiddian Stage - to - Caradoc Series (Ordovician Period) (468-449.75 Ma BP)."@en . "Unconformably overlain by the Craighead Limestone Formation."@en . "Lower boundary not seen."@en . . . "Arenig Ballantrae Volcanic Complex (assumed to be part of) [Obsolete: use CRV]"@en . "Craighead Volcanic Formation"@en . "468.0"^^ . . "At least 500 m thick."@en . "CRV"@en .