The BGS Lexicon of Named Rock Units — Result Details

Hagley Volcanic Group [Obsolete Name And Code: See HGY]

Computer Code: HVG Preferred Map Code: notEntered
Status Code: Index Level
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Crystal and lithic tuffs, agglomerates, breccias with thin interbedded shales.
Definition of Lower Boundary: Drawn at the base of the Hayley Ash Formation where it rests conformably upon the Aldress Shales Formation of the Aldress Group.
Definition of Upper Boundary: Drawn at the conformable upward passage from volcanics of the Hagley Volcanic Group to shales of the Hayley Shales Formation.
Thickness: 106 metres approx.
Geographical Limits: Chirbury, West Shropshire, England.
Parent Unit: Not Entered (?)
Previous Name(s): none recorded or not applicable
Alternative Name(s): Hagley Volcanic Formation
Stratotypes:
Type Area  Hagley Quarry, near Chirbury. 
Reference(s):
Lapworth, C . 1887. The Ordovician rocks of Shropshire. British Association for the Advancement of Science. Report for 1886. Birmingham Meeting 662. 
Lapworth, C, 1916. Palaentological Work. Summary of progress for 1915. p.36. 
Williams, A and others, 1972. A correlation of Ordivician rocks in the British Isles. Geological Society of London Special Report No.3. 
Whittard, W F. 1931. The geology of the Ordovician and Valentian rocks of the Shelve Country, Shropshire. Proceedings of the Geologists' Association, Vol.42, 322-344. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable