The BGS Lexicon of Named Rock Units — Result Details
Cardingmill Grit Member
Computer Code: | CDDG | Preferred Map Code: | notEntered |
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Status Code: | Pending Upgrade | ||
Age range: | Ediacaran Period (AD) — Ediacaran Period (AD) | ||
Lithological Description: | Massive to thick-bedded and cross-bedded coarse-grained sandstones, commonly micaceous and locally pebbly, with a few thin siltstone beds. | ||
Definition of Lower Boundary: | The base is transitional over a few metres, but is generally taken at the base of the first thick bed of coarse grained sandstone that succeeds relatively thinly interbedded fine grained, cross-bedded sandstones and mudstones of the Burway Formation. | ||
Definition of Upper Boundary: | Drawn at the relatively sharp conformable upward passage from coarse sandstones of the Cardingmill Grit to purple mudstones and siltstones of the Synalds Formation. | ||
Thickness: | Usually 25-30 m, but may achieve 58 m locally. | ||
Geographical Limits: | Welsh Borderlands, Shropshire, Church Stretton and the Longmynd area. | ||
Parent Unit: | Burway Formation (BUGP) | ||
Previous Name(s): | Cardingmill Grit [Obsolete Code: Use CDDG]
(YSBC)
Carding Mill Grit [Obsolete Name and Code: Use CDDG] (-2675) |
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Alternative Name(s): | none recorded or not applicable | ||
Stratotypes: | |||
Reference Section | Devil's Mouth, Ashes Hollow, 780 m north west of ashes cottage. Wilson D. 2000. | ||
Reference(s): | |||
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. | |||
Lapworth C and Watts W W. 1910. Shropshire. 739-769 in Geology in the field; the Jubilee Volume of the Geologists' Association (1858-1908). Monckton H W and Herries R S (editors). (London: Edward Stanford). | |||
Pauley J C. 1990. The Longmyndian Supergroup and related Precambrian sediments of England and Wales. 5-27 in Avalonian and Cadomain geology of the North Atlantic. Strachan R A and Taylor G K (editors). (Glasgow: Blackie). | |||
Pauley J C. 1990. Sedimentology, structural evolution and tectonic setting of the Late Precambrian Longmyndian Supergroup of the Welsh Borderland, UK. 341-351 in the Cadomian Orogeny. D'Lemos R S, Strachan R A and Topley C G (editors). Geological Society of London Special Publication No. 51. | |||
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. | |||
Wilson, D, 2000. Shropshire. 81-113 in Precambrian rocks of England and Wales. Carney, J N (editor). Geological Conservation Review Series No. 20. (Peterborough: Joint Nature Conservation Committee). | |||
1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
E166 |