The BGS Lexicon of Named Rock Units — Result Details
Cefn Coch Grit Member
| Computer Code: | CEG | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | St David's Series (ED) — St David's Series (ED) | ||
| Lithological Description: | Coarse-grained, quartzose, thick-bedded turbiditic sandstones. | ||
| Definition of Lower Boundary: | Conformable within the silty mudstones that form the main part of the Gamlan Formation. | ||
| Definition of Upper Boundary: | Conformable within the upper part of the Gamlan Formation, but may locally form the top of the latter at its junction with the overlying flaggy sandstones and mudstones of the Mawddach Group. | ||
| Thickness: | Up to 15m | ||
| Geographical Limits: | Harlech area, North Wales. | ||
| Parent Unit: | Gamlan Formation (GN) | ||
| Previous Name(s): | Cefn Goch Grit [Obsolete Name and Code: Use CEG]
(-3290)
Menevian Grit [Obsolete Name and Code: Use CEG] (-2068) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Pistyll y Cain, within the Afon Gam, near the Mawddach waterfalls. About 1.3km northnortheast of Ganllwyd. Matley, and Wilson, 1946. | ||
| Reference(s): | |||
| Allen, P M, and Jackson, A A. 1985. Geology of the country around Harlech. Memoir of the British Geological Survey, Sheet 135 with part of Sheet 149 (England and Wales). (London: HMSO.) 112 pp. | |||
| Matley, C A and Wilson, T S. 1946. The Harlech Dome, North of the Barmouth Estuary. Quarterly Journal of the Geological Society of London, Vol.102, 1-40. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| none recorded or not applicable | |||