The BGS Lexicon of Named Rock Units — Result Details

Pistyll Gwyn Mudstones Formation

Computer Code: PIG Preferred Map Code: PiG
Status Code: Full
Age range: Rhuddanian Age (SR) — Aeronian Age (SA)
Lithological Description: Interbedded grey turbidite mudstones and laminated hemipelagites. Scattered thin turbidite sandstones.
Definition of Lower Boundary: Gradational but taken at base of first thick mudstone unit above the Allt-y-Clych Conglomerate.
Definition of Upper Boundary: Not seen.
Thickness: Up to 400m.
Geographical Limits: Central Wales, east of Tywi Anticline.
Parent Unit: Not Entered (?)
Previous Name(s): Pistyll Gwyn Mudstones Member [Obsolete Name and Code: Use PIG] (-2372)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Cutting behind Pistyll Gwyn Farmyard, Llanyre, Powys. 
Reference(s):
none recorded or not applicable
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E179