The BGS Lexicon of Named Rock Units — Result Details

Upper Greensand Formation (Devon) [Obsolete Name And Code: See UGS]

Computer Code: UGSD Preferred Map Code: UGS
Status Code: Index Level
Age range: Albian Age (KA) — Cenomanian Age (KE)
Lithological Description: Unconsolidated non-calcareous sands (with glauconite), chert and cherty sandstone, thin clay seams and shell beds. A few calcite-cemented sandstones and limestones in the Bovey Basin, especially at Wolborough [SX 855 700]. Locally gravelly. Divided into four members. NOTE: Callum Sands with Cherts Member (sand with cherts, 6.7m); Ashcombe Gravels Member (sandy quartz gravels and coarse gravelly quartz sands, 5.3m); Woodlands Sands Member (glauconitic clayey sands, shell beds, sands with siliceous concretions, 4.1m); Telegraph Hill Sands Member (green glauconitic sands, 5.3m).
Definition of Lower Boundary: In the Haldon Hills the sands of the unit rest unconformably on breccias of the Permian Exeter Group. In the Bovey Basin they rest variably on Devonian, Carboniferous and Permian rocks.
Definition of Upper Boundary: The Upper Greensand Formation is overlain in the Haldon Hills by the Tower Wood Gravel with a sandy flint-free bed up to 12.5cm thick with well-rounded quartz and schorl pebbles at the junction (Pickard, 1949). In the Bovey Basin the unit is generally overlain by the Aller Gravel (Edwards, 1973), but Tower Wood Gravel locally intervenes (Brunsden and others, 1976).
Thickness: At least 76m (Haldon Hills); c.20m (Bovey Basin).
Geographical Limits: Present on Haldon Hills and on east and south of Bovey Basin between Newton Abbot and Badcombe Copse [SX 869 766].
Parent Unit: Not Applicable (-)
Previous Name(s): Haldon Sands Formation (-4417)
Haldon Sands (-1299)
Alternative Name(s): Upper Greensand Formation
Stratotypes:
Reference Section  Head of Cullum Goyle. Cullum Sands with cherts. 
Type Section  Woodlands, north end of Great Haldon, Devon. Temporary gully. Cullum Sands with Cherts Member (Beds 20-23). Ashcombe Gravels Member (Beds 15-19). Woodlands Sands Member (7-14). Telegraph Hill Sands Member (Beds 1-6). (Hamblin and Woods, 1976). 
Reference Section  West of Ashcombe. Ashcombe Gravels. 
Reference Section  Telegraph Hill: Telegraph Hill Sands. 
Reference(s):
Brunsden, D and others. 1976. Tertiary and Cretaceous sediments in solution pipes in the Devonian Limestone of south Devon. Geological Magazine, Vol.113, p.441-447. 
Ussher, W A E, 1913. Geology of the country around Newton Abbot. Memoir of the British Geological Survey, Sheet 339. (England and Wales). 
Jukes-Browne, A J and Hill, W. 1900. The Cretaceous Rocks of Britain. 1. Gault and Upper Greensand. Memoir of the Geological Survey of Great Britain. 
Pickard, R, 1949. The Geology of Milber Down. Report and Transactions of the Devonshire Association for the Advancement of Science, Vol.81, p.217-226. 
Hamblin, R J O and Wood, C J. 1976. The Cretaceous (Albian-Cenomanian) stratigraphy of the Haldon Hills, south Devon, England. Newsletters on Stratigraphy, Vol.4, 135-149. 
Edwards, R A, 1973. The Aller Gravels: Lower Tertiary Braided River Deposits in South Devon. Proceedings of the Ussher Society, Vol.2, p.608-616. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E339