"Barras Conglomerate Formation [Obsolete: use BACO]"@en . "Apparently conformable, probably diachronous, at the base of the lavas of the Montrose Volcanic Formation."@en . . "410.5"^^ . "BACO"@en . . "A conformable and diachronous passage down and laterally south into the St. John's Knap Sandstone Member, delineated at the point where conglomerate becomes predominant upwards from the underlying formation."@en . . . . "From 100 m to 255 m thick."@en . "Johnshaven Formation [Obsolete: use BACO, CATC, SJKS, TWSA]"@en . "stable"@en . "Conglomerate with subsidiary sandstone. Stratified bedrock. Occurs onshore. Deposited during the Lochkovian Age - to - Pragian Age (Devonian Period) (419-410.5 Ma BP)."@en . "Barras Conglomerate Member"@en . . "419.0"^^ . . "Barras Conglomerate Member"@en . "A bimodal, clast-supported conglomerate with clasts mainly of lava, with psammite, quartzite, vein-quartz and feldspar porphyry in a coarse-grained lithic sandstone matrix."@en . .