The BGS Lexicon of Named Rock Units — Result Details

Quartz Conglomerate Group (South Wales) [Obsolete: use CWA, PENN, POB]

Computer Code: QCG Preferred Map Code: notEntered
Status Code: Full, pending ratification
Age range: Famennian Age (DA) — Famennian Age (DA)
Lithological Description: [Obsolete: use CWA, PENN, POB] An upper portion of sandstones with alternations of marl, and a lower portion of lenticular quartz-conglomerate beds with sandstones, grits and quartzites.
Definition of Lower Boundary: Drawn at the base of lenticular quartz-conglomerate beds with sandstones, grits and quartzites, where they rest unconformably on Early Devonian sandstones of the Brownstones Formation.
Definition of Upper Boundary: Drawn at the conformable upward passage from sandstones and marls of the Quartz Conglomerate Group into limestones and calcareous mudstones of the "Carboniferous Limestone" [generally the Lower Limestone Shale Group or its lateral equivalents].
Thickness: c.77m
Geographical Limits: South Glamorgan, Cardiff, South Wales.
Parent Unit: none recorded or not applicable
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Cardiff District. 
Reference(s):
Robertson, T, 1927. South Wales Coalfield, part 2. Abergavenny, 2nd Edition.Memoirs of the Geological Survey of Great Britain, p.42. 
Heard, A and Davies, R. 1924. The Old Red Sandstone of the Cardiff district. Quarterly Journal of the Geological Society, Vol.80, 489-519. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E232 E263 E262 E249 E247 E231