The BGS Lexicon of Named Rock Units — Result Details
Ashcombe Gravel Member
| Computer Code: | ACGR | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Albian Age (KA) — Cenomanian Age (KE) | ||
| Lithological Description: | The member comprises three beds of coarse-grained sandstone and quartz gravel, separated by two coarse-grained, poorly sorted sandstone units, which show local cross-bedding and contain clay seams. The only common fossils are silicified oysters in the basal gravel. | ||
| Definition of Lower Boundary: | Contact with the underlying Woodlands Sands Member. Upward facies-change from glauconitic clayey sandstones (Woodlands Sands Member) to coarse sandstones and gravels (Ashcombe Gravels Member). | ||
| Definition of Upper Boundary: | Contact with the overlying Cullum Sands-with-Cherts Member, marked by the upward facies change from coarse-grained sandstones and gravels (Ashcombe Gravels Member) to sandstones containing chert horizons (Cullum Sands-with-Cherts Member). | ||
| Thickness: | 5.28m. | ||
| Geographical Limits: | Haldon Hills, Devon, Sheet 339. | ||
| Parent Unit: | Upper Greensand Formation (UGS) | ||
| Previous Name(s): | Haldon Sands Formation [Obsolete Name and Code: Use ACGR, CUSC, UGSD, WLSS]
(-4417)
Haldon Sands [Obsolete Name and Code: Use UGSD, ACGR, CUSC, THSS, WLSS] (-1299) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Temporary road cutting at Woodlands Goyle [SX 902 840], at the north end of Great Haldon, Selwood et al. (1984). | ||
| Reference Section | Babcombe Copse Sandpit [SX 869 766], Selwood et al. (1984). | ||
| Reference(s): | |||
| 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. | |||
| Ussher, W A E. 1913. Geology of the country around Newton Abbot. Memoir of the British Geological Survey, Sheet 339. (England and Wales). | |||
| Selwood, E B, Edwards, R A, Simpson, S, Chesher, J A, Hamblin, R J O, Henson, M R, Riddolls, B W and Waters, R A. 1984. Geology of the countryside 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. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| none recorded or not applicable | |||