The BGS Lexicon of Named Rock Units — Result Details

Bangor Formation

Computer Code: BGOR Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Comley Series (EC) — Comley Series (EC)
Lithological Description: Volcanogenic sandstone and conglomerate, overlain by laminated fine-grained acid tuffites, including tuffaceous sandstone, siltstone and mudstone.
Definition of Lower Boundary: Taken at the angular unconformity that separates the formation from the underlying volcaniclastic rocks of the Minfordd Formation.
Definition of Upper Boundary: Taken at the conformable transition into the purplish red siltstones of the Llanberis Slates Formation.
Thickness: Up to 240 m thick.
Geographical Limits: In the immediate vicinity of Bangor, North Wales.
Parent Unit: Arfon Group (ARN)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Area  Bangor Mountain. 
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. 
Smith, B and George, T N. 1961. North Wales. British Regional Geology. (London: H.M.S.O.). 97pp. 
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. 
Howells, M F, Reedman, A J and Leveridge, B E, 1985. Geology of the country around Bangor. Explanation for 1: 50 000 sheet 106 (England and Wales). 
Shackleton, R M. 1975. Precambrian rocks of Wales. 76-83 in A correlation of Precambrian rocks in the British Isles. Harris, A L, and others (editors). Geological Society of London Special Report No. 6. 
1:50K maps on which the lithostratigraphical unit is found, and map code used: