The BGS Lexicon of Named Rock Units — Result Details

Coralliferous Group

Computer Code: CRX Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Telychian Age (ST) — Wenlock Epoch (SW)
Lithological Description: Grey shales and mudstones, thin calcareous grits, and argillaceous limestones with abundant corals.
Definition of Lower Boundary: Drawn at the base of the Coralliferous Group where shale rests conformably upon conglomerate of the Conglomerate Group.
Definition of Upper Boundary: Drawn at the conformable upward passage of the Limestone Beds of the Coralliferous Group with the sandstone of the Sandstone Group.
Thickness: 170m max./approx.
Geographical Limits: Marloes Bay, Pembrokeshire.(now Dyfed).
Parent Unit: Not Applicable (-)
Previous Name(s): Coralliferous Series (-3335)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Marloes Sands, Dyfed. 
Reference(s):
Cantrill, T C and others, 1916. South Wales Coalfield, part XII, Milford. Memoir of the Geological Survey of Great Britain. 
De La Beche, H. 1846. On the formation of rocks of south Wales and south-west England. Memoir of the Geological Survey of Great Britain, No.1. 
St Joseph, J K S. 1935. A critical examination of Stricklandia lirata (J de C Sowerby) 1839, forma typica. Geological Magazine. Vol.72, 421-422. 
Jones, O T, 1921. The Valentian Series. Quarterly Journal of the Geological Society, Vol.77, p.154-157. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable