| Computer Code: |
DOG |
Preferred Map Code: |
DoG |
| Status Code: |
Full |
| Age range: |
Comley Series (EC)
— Comley Series (EC) |
| Lithological Description: |
Fine- to medium-grained sandstone with siltstone, pebbly sandstone and conglomerate. |
| Definition of Lower Boundary: |
Unexposed. Seen in the Bryn-teg Borehole, the base appears to lie unconformably on rocks of the Bryn-teg Volcanic Formation. |
| Definition of Upper Boundary: |
Overlain by the Llanbedr Formation. The boundary is conformable and transitional. |
| Thickness: |
575m |
| Geographical Limits: |
Core of the Dolwen Pericline (upper part); lower part proved in the Bryn-teg Borehole, SH63SE/1 [SH 6992 3214] . |
| Parent Unit: |
Harlech Grits Group (HGG)
|
| Previous Name(s): |
Dolwen Grits [Obsolete Name and Code: Use DOG]
(-1512)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Partial Type Section |
West and south of Bryn-teg Farm. |
| Partial Type Section |
Afon Crawcwellt. For the purple sandstones at the top of the Formation. |
| 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. |
| Allen, P M, and Jackson, A A. 1978. Bryn-teg Borehole, North Wales. Bulletin of the Geological Survey of Great Britain, No. 61. |
| 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. |
| 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: |
|
E135
|
