| Computer Code: |
CYBR |
Preferred Map Code: |
CaBr |
| Status Code: |
Full |
| Age range: |
Permian Period (P)
— Permian Period (P) |
| Lithological Description: |
Brown to reddish-brown unbedded to very roughly bedded breccia, consisting of angular to subrounded pebbles and cobbles of Culm Sandstone in very poorly sorted gritty, clayey, sandy, silt. The clasts are mainly locally derived Culm Sandstone generally not exceeding 0.3m diameter; other clasts include vein quartz, chert and fossiliferous sandstone of Pilton Beds type. Unnamed unit of sand and clay mapped with Cadbury Breccia between Greenslinch (SS 969 035) and Hele (SS 999 030). |
| Definition of Lower Boundary: |
Rests unconformably on Bude Formation or Crackington Formation. |
| Definition of Upper Boundary: |
Overlain in eastern part of Crediton Trough by Thorverton Sandstone (q.v.), Crediton Breccia (q.v.) or Bow Breccia (q.v.). |
| Thickness: |
Up to 270m |
| Geographical Limits: |
Extends along northern side of Crediton Trough from near Lower Creedy, Crediton (SS 845 030), eastwards to near Clyst Hydon. |
| Parent Unit: |
Exeter Group (EXE)
|
| Previous Name(s): |
Cadbury Beds [Obsolete Name and Code: Use CYBR]
(-2735)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Cadbury (SS 911 049) near Thorverton. Name derived from village of Cadbury, Devon. No good natural sections: artificial cuttings at: Cadbury (SS 9113 0488), Raddon Hill Farm (SS 9041 0309), Coombe Barton (SS 8746 0273). |
| Reference(s): |
| Hutchins, P F, 1958. Devonian limestone pebbles in central Devon. Geological Magazine, Vol.95, p.119-124. |
| Edmonds, E A, Wright, J E, Beer, K E, Hawkes, J R, Fenning, P J, Freshney, E C, Lovelock, P E R, McKeown, M C, Ramsbottom, W H C and Williams, M. 1968. Geology of the country around Okehampton. Memoir of the Geological Survey of Great Britain, Sheet 324 (England and Wales). |
| Hutchins, P F, 1963. The Lower New Red Sandstone of the Crediton Valley. Geological Magazine, Vol.100, 107-128. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
