Computer Code: |
PVC |
Preferred Map Code: |
PVC |
Status Code: |
Pending Upgrade |
Age range: |
Ediacaran Period (AD)
— Ediacaran Period (AD) |
Lithological Description: |
Fine- to coarse-grained, feldspathic and porcellanitic ("halleflinta") crystal lithic tuffs, with volcaniclastic conglomerates in the lower part. |
Definition of Lower Boundary: |
Unknown; appears to be conformable on Lower Pebidian strata (undivided). |
Definition of Upper Boundary: |
Unknown; appears to be conformably overlain by the Ramsey Sound Group. |
Thickness: |
At least 600m |
Geographical Limits: |
St David's area, Pembrokeshire. |
Parent Unit: |
Pebidian Supergroup (PN)
|
Previous Name(s): |
Caerbwdy Series [Obsolete Name and Code: Use PVC]
(-3626)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Reference Section |
Crags to the east of Treginnis-isaf. Within the lower part of the succession. |
Reference Section |
Quarries along the Caerbwdy Valley, south of Trevinert. Green, 1908 |
Reference(s): |
Green, J F N. 1908. The geological structure of the Saint David's area (Pembrokeshire). Quarterly Journal of the Geological Society of London, Vol.64, 363-383. |
George, T N. 1970. British Regional Geology, South Wales, Third Edition. British Geological Survey. |
Pharaoh T C and Gibbons W. 1994. Precambrian rocks in England and Wales south of the Menai Strait Fault System. 85-97 in Gibbons W and Harris A L (editors), A revised correlation of Precambrian rocks in the British Isles. Geological Society of London Special Report No.22. |
Bevins, R E, and Horak, J. 2000. St David's Peninsula. 131-136 in Precambrian Rocks of England and Wales. Carney, J (editor). Geological Conservation Review Series, 20. (Peterborough: Joint Nature Conservation Committee.) |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E209
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