. "A thick pile of andesitic lava with associated pyroclastic and reworked volcanic rocks, subordinate biotite-phyric rhyolite and tuff."@en . "At least 1000 m thick."@en . "Cheviot Lavas [Obsolete: use CHEV]"@en . . "Andesite, biotite-phyric rhyolitic-rock and volcaniclastic rocks (both pyroclastic and reworked volcanic rocks) with subsidiary pyroclastic-breccia and tuff. Stratified bedrock. Occurs onshore. Deposited during the Early Devonian Epoch (Devonian Period) (419-394.3 Ma BP)."@en . "CHEV"@en . . . . "Cheviot Volcanic Series [Obsolete: use CHEV]"@en . . "394.3"^^ . "419.0"^^ . "The base of the volcanic rocks resting unconformably on Wenlock strata or, locally the White Hill Sandstone Formation."@en . . "The top of the volcanic pile, uncomnformably overlain by the upper Devonian to lower Carboniferous rocks."@en . . . . "stable"@en . "Cheviot Volcanic Formation"@en . "Cheviot Volcanic Group [Obsolete: use CHEV]"@en . . . "Cheviot Volcanic Formation"@en .