The BGS Lexicon of Named Rock Units — Result Details
Glyn Formation
| Computer Code: | GYN | Preferred Map Code: | GyN |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Rawtheyan Stage (OW) — Hirnantian Age (OH) | ||
| Lithological Description: | Fine- to coarse-grained sandstones and thin siltstones; a locally developed limestone member (Glyn Limestone) at base on Mynydd Fron Frys. | ||
| Definition of Lower Boundary: | Top of underlying micaceous siltstones and mudstones of the Dolhir or Cyrn-y-Brain Beds. | ||
| Definition of Upper Boundary: | Overlain by shales and slates of the Fron Frys Formation. | ||
| Thickness: | 21-70m | ||
| Geographical Limits: | Glyn Ceiriog and Llanelidan-Eglwyseg area of east Wales. | ||
| Parent Unit: | Not Applicable (-) | ||
| Previous Name(s): | Glyn Grit [Obsolete Name and Code: Use GYN]
(-4077)
Glyn Grit And Limestone [Obsolete Name And Code: See GYN] (GLG) |
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| Alternative Name(s): | Corwen Grit Member |
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| Stratotypes: | |||
| Type Area | Type area around Glyn Ceiriog. Section on Mynydd Fron Frys, south east of Glyn Ceiriog. | ||
| Reference(s): | |||
| Groom, T, Lake, P, 1908. Glyn Grit. Quarterly Journal of the Geological Society, Vol.64. | |||
| Hiller, A, 1981. The Ashgill rock of the Glyn Ceiriog district, north Wales. Geological Journal, Vol.16, p.181-200. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E121 E120 E137 | |||