The Ceiswyn Formation (also known as the Ceiswyn Beds) is an Ordovician lithostratigraphic group (a sequence of rock strata) in Mid Wales. The rock of...
3 KB (188 words) - 11:45, 25 November 2023
valley of the Nant Ceiswyn, and Cwm Hengae lies to the south. Two minor dip faults cross the mountain, and the Ceiswyn Formation is named after this...
2 KB (79 words) - 22:36, 24 March 2023
Ordovician age. They comprise the mudstones and siltstones of the Ceiswyn Formation which form much of the southern part of the mountain, together with...
17 KB (1,830 words) - 01:27, 1 September 2024
The Nod Glas Formation (also known as the Nod Glas Black Shale, the Cadnant Shale, the Penarwel Mudstones or just Nod Glas) is an Ordovician lithostratigraphic...
5 KB (492 words) - 11:53, 22 June 2024
the Ordovician Period. The main ridge is developed in rocks of the Ceiswyn Formation assigned to the Ogwen Group and dating from around 457 to 454 million...
3 KB (347 words) - 23:11, 16 June 2024
(L) Afon Llyfnant (L) Afon Dulas (R) (North Dulas) Afon Deri (R) Nant Ceiswyn (R) Afon Dulas (L) (South Dulas) Afon Twymyn (L) Afon Rhiwsaeson (R) Afon...
24 KB (2,643 words) - 22:10, 15 August 2024