. "CAEC"@en . "Cae Castell Formation"@en . "Sandstone and siltstone with subsidiary mudstone. Stratified bedrock. Occurs onshore. Deposited during the Wenlock Epoch (Silurian Period) (432.9-426.7 Ma BP)."@en . . . . . "stable"@en . "Cae Castell Formation"@en . . "432.9"^^ . . "Wenlock Beds [Obsolete: use CAEC]"@en . . "Sandstones, siltstones and subordinate mudstones."@en . "Taken at the conformable base of the fine- to coarse-grained sandstones and pebbly sandstones of the Rhymney Grit Member, which sharply overlies the Pen-y-lan Mudstone."@en . "Sharply and conformably overlain by the mudstones with thin sandstones and siltstones of the Cardiff Group."@en . . "70 to 80m"@en . "426.7"^^ .