The BGS Lexicon of Named Rock Units — Result Details

Skerries Formation

Computer Code: NK Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Massive greenish-grey schistose greywackes, coarse and often pebbly, followed by unstratified dull greenish-grey pyroclastic rocks of intermediate composition.
Definition of Lower Boundary: Drawn at the base of the Skerries Formation where it rests conformably upon pelites and semipelites with pillow lavas of the New Harbour Group.
Definition of Upper Boundary: Drawn at the conformable upward passage from the top of the Church Bay Tuff Formation to the limestone, graphitic pelite and other quartzite;- triple formation of the Gwna Group.
Thickness: 500 metres approx.
Geographical Limits: Anglesey, north Wales.
Parent Unit: New Harbour Group (NNH)
Previous Name(s): Skerries Conglomerates (NKSC)
Skerries Grits (NKSG)
Skerries Group (-421)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  The Skerries, near Carmel Head, Anglesey. 
Reference(s):
Greenly E. 1919. The geology of Anglesey, Vol 1. Memoir of the Geological Survey of Great Britain (England and Wales). (London: H.M.S.O.). 
Harris, A L and others, 1973. A correlation of the Pre-Cambrian rocks in the British Isles. Geological Society of London Special Report No 6. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable