The BGS Lexicon of Named Rock Units — Result Details

Cerrig Gwynion Grits Facies (Caban Conglomerate Formation)

Computer Code: CYG Preferred Map Code: CyG
Status Code: Pending Upgrade
Age range: Hirnantian Age (OH) — Llandovery Epoch (SL)
Lithological Description: Medium- to coarse-grained, thick-bedded sandstones, pebbly in places.
Definition of Lower Boundary: No definition.
Definition of Upper Boundary: No definition.
Thickness: No definition.
Geographical Limits: Central Wales.
Parent Unit: Caban Conglomerate Formation (CBN)
Previous Name(s): Cerrig Gwynion Grits Member [Obsolete Name and Code: Use CYG] (-3343)
Cerrigwynion Grits [Obsolete Name and Code: Use CYG] (-4582)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Rhayader Quarry. The quarry has quarried away the crags called Cerrig Gwynion after which Lapworth, (1900) named his original stratigraphic unit. 
Reference(s):
Lapworth, H, 1900. The Silurian sequence at Rhayader. Quarterly Journal of the Geological Society, Vol.56, p.67-137. 
Definition not published. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E179