| Computer Code: |
BGOR |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Comley Series (EC)
— Comley Series (EC) |
| Lithological Description: |
Volcanogenic sandstone and conglomerate, overlain by laminated fine-grained acid tuffites, including tuffaceous sandstone, siltstone and mudstone. |
| Definition of Lower Boundary: |
Taken at the angular unconformity that separates the formation from the underlying volcaniclastic rocks of the Minfordd Formation. |
| Definition of Upper Boundary: |
Taken at the conformable transition into the purplish red siltstones of the Llanberis Slates Formation. |
| Thickness: |
Up to 240 m thick. |
| Geographical Limits: |
In the immediate vicinity of Bangor, North Wales. |
| Parent Unit: |
Arfon Group (ARN)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Bangor Mountain. Reedman, A J et al., 1984. |
| Reference(s): |
| Greenly, E. 1946. The Monio-Cambrian interval. Geological Magazine, Vol. 83, 237-240. |
| Reedman, A J, Leveridge, B E and Evans, R B. 1984. The Arfon Group (Arvonian?) of North Wales. Proceedings of the Geologists' Association, Vol.95, 313-321. |
| Howells M F, Reedman A J and Leveridge B E. 1985. Geology of the country around Bangor: Explanation for 1:50 000 geological sheet 106 (England and Wales). British Geological Survey Sheet Explanation. [London: HMSO.] 34pp. |
| Greenly, E. 1944. The Arvonian rocks of Arvon. Quarterly Journal of the Geological Society, London, 100, 269-287. |
| Smith, B and George, T N. 1961. North Wales. British Regional Geology. (London: H.M.S.O.). 97pp. |
| Shackleton, R M. 1975. Precambrian rocks of Wales. 76-83 in A correlation of Precambrian rocks in the British Isles. Harris, A L, and others (editors). Geological Society of London Special Report No. 6. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E106
|
