The BGS Lexicon of Named Rock Units — Result Details
Grey Grits Formation
| Computer Code: | GRG | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Famennian Age (DA) — Tournaisian Age (CT) | ||
| Lithological Description: | Grey, greenish or buff quartzitic sandstones in mainly tabular beds with sharp, erosional contacts. | ||
| Definition of Lower Boundary: | At base of lowest grey quartzitic bed where it rests sharply or slightly erosionally on red sandstone of the underlying Plateau Beds Formation. | ||
| Definition of Upper Boundary: | At top of highest quartzitic sandstone bed where it is sharply or erosionally overlain by a thin conglomerate at the base of the Castell Coch Limestone Formation. | ||
| Thickness: | Up to 19 m. | ||
| Geographical Limits: | none recorded or not applicable | ||
| Parent Unit: | Quartz Conglomerate Formation (QTZC) | ||
| Previous Name(s): | Grey Grits
(GGRIT)
Grey Grits (GGRIT) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Abercriban Quarries, Powys, South Wales; the more northerly of two quarries provides a complete section [SO 0638 1272]. Lovell, 1975a, b; Barclay, in press. | ||
| Reference(s): | |||
| Lovell, R W W. 1978a. The sedimentology and stratigraphy of the Upper Old Red Sandstone and Lower Limestone Shales of the South Wales Coalfield. Unpublished PhD thesis, University of Bristol. | |||
| Lovell, R. 1975. Abercriban, Powys. Pp. 72-73 in Friend, P. F. and Williams, B. P. J. (editors). International Symposium on the Devonian System (P.A.D.S. 1978) September 1978. A field guide to selected outcrop areas of the Devonian of Scotland, the Welsh Borderland and South Wales. The Palaeontological Association. | |||
| Barclay, W J. 2005. Abercriban Quarries. In Barclay, W J et al. The Old Red Sandstone rocks of Great Britain. JNCC Review Series. | |||
| Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E231 E230 | |||