The BGS Lexicon of Named Rock Units — Result Details

Ragleth Tuff Formation

Computer Code: RT Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Pink, brown, purple and green, tuffaceous mudstones, siltstones and sandstones, with beds of fine-grained lithic felsic tuff.
Definition of Lower Boundary: Faulted.
Definition of Upper Boundary: Uncertain. Considered by Greig et al (1968) to be an unconformity, but Cobbold and Whittard (1935) and Pauley (1991) suggested a conformable contact with the Helmeth Grits, based on lithological similarities with the latter.
Thickness: More than 450m
Geographical Limits: Welsh Borderlands, Shropshire, Church Stretton area.
Parent Unit: Stretton Group (YST)
Previous Name(s): Ragleth Tuffs [Obsolete Name And Code: Use RT] (URT)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Southern ridge of Caer Caradoc Hill, Church Stretton. Greig, D C et al. 1968. 
Reference Section  Three Fingers Rock, southern spur of Caer Caradoc Hill, 1km northwest of Church Stretton. Greig, D C et al. 1968. 
Reference(s):
Cobbold, E S and Whittard, W F, 1935. The Helmeth Grits of the Caradoc Range, Church Stretton; their bearing on part of the Pre-Cambrian succession of Shropshire. Proceedings of the Geologists' Association, Vol.46, 348-359. 
Greig D C, Wright, J E, Hains, B A and Mitchell, G H. 1968. Geology of the country around Church Stretton, Craven Arms, Wenlock Edge and Brown Clee. Memoir of the Geological Survey, Sheet 166 (England and Wales). (London: H.M.S.O.). 379pp. 
Pauley J C. 1991. A revision of the stratigraphy of the Longmyndian Supergroup, Welsh Borderland, and of its relationship to the Uriconian volcanic complex. Geological Journal, Vol. 26, 167-183. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable