The BGS Lexicon of Named Rock Units — Result Details

Baron Hill Formation

Computer Code: BAH Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Ediacaran Period (AD) — Comley Series (EC)
Lithological Description: Tuffaceous mudstones interbedded with massive, coarse-grained tuffaceous sandstones and conglomerates, containing clasts of felsic welded tuff, basalt and basaltic hyaloclastite.
Definition of Lower Boundary: Unknown, however Greenly (1919) supposed that it overlay the Gwna Melange (now Gwna Group) of Anglesey, but there is some doubt about this, given the current uncertainties on the age of these divisions.
Definition of Upper Boundary: Unknown; probably unconformably overlain by Ordovician strata along its southeastern crop.
Thickness: At least 300 m thick.
Geographical Limits: 1:50,000 Geological Sheet 106 (Bangor). The formation represents part of the Arfon Group of the mainland that extends onto Sheet 105 Caernarfon.
Parent Unit: Arfon Group (ARN)
Previous Name(s): Baron Hill Rocks [Obsolete Code: Use BAH] (OBH)
Baron Hill Beds (-3189)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Crags alongside track leading through Coed Parc to Baron Hill. Greenly, E, 1919. 
Reference(s):
Greenly E. 1946. The Monio-Cambrian interval. Geological Magazine, Vol. 83, 237-240. 
Carney J N and others. 2000. Precambrian rocks of England and Wales. Geological Conservation Review Series. No 20. [Peterborough: Joint Nature Conservation Committee]. 252pp. 
Reedman, A J, Leveridge, B E and Evans, R B. 1984. The Arfon Group (Arvonian?) of North Wales. Proceedings of the Geologists' Association, Vol.95, 313-321. 
Greenly E. 1944. The Arvonian rocks of Arvon. Quarterly Journal of the Geological Society, London, 100, 269-287. 
Greenly E. 1919. The Geology of Anglesey, Vol 2. Memoir of the Geological Survey of Great Britain [England and Wales]. [London: H.M.S.O.]. 
Greenly E. 1919. The Geology of Anglesey, Vol 2. Memoir of the Geological Survey of Great Britain [England and Wales]. [London: H.M.S.O.]. 
Reedman A J, Leveridge B E and Evans R B. The Arfon Group ("Arvonian")] of North Wales. Proceedings of the Geologists' Association, Vol.95, 313-321. 
Greenly E. 1944. The Arvonian rocks of Arvon. Quarterly Journal of the Geological Society of London, Vol. 100, 269-284. 
Greenly, E. 1946. The Monio-Cambrian interval. Geological Magazine, Vol. 83, 237-240. 
Carney J N and_ others. 2000. Precambrian rocks of England and Wales. Geological Conservation Review Series. No 20. [Peterborough: Joint Nature Conservation Committee]. 252pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E093 E105