. "About 140 m thick, although estimated at over 300 m thick by some authors."@en . . . . . "stable"@en . "Balnakiel Formation"@en . "Conformably overlain by the Croisaphuill Formation."@en . "Alternations of dark grey dolostones and dolomitic limestones and lighter grey bioclastic limestones."@en . . "477.1"^^ . "BNK"@en . "Dolomitic limestone, dolostone and limestone with subsidiary breccia, chert and mudstone. Stratified bedrock. Occurs onshore. Deposited during the Arenig Series (Ordovician Period) (477.1-468 Ma BP)."@en . "468.0"^^ . "Balnakiel Formation"@en . "Conformably overlies the Sangomore Formation."@en . . . "Balnakiel Group [Obsolete: use BNK]"@en . .