The BGS Lexicon of Named Rock Units — Result Details

Sandringham Sand Formation

Computer Code: SAS Preferred Map Code: SaS
Status Code: Full
Age range: Tithonian Age (JI) — Valanginian Age (KV)
Lithological Description: The formation comprises silty and clayey sands, sporadic clay ironstones, with cleaner quartz sands at the top. Four members are recognised [Casey and Gallois, 1973; Gallois, 1984, 1994]: Incoherant, moderately clean, pale grey [locally green, yellow or orange]. fine- to medium-grained, cross-bedded quartz sands with surbordinate bands of silt or clay. Pyrite nodules are present and glauconite is locally abundant. [Leziate Sand Member]. Glauconitic, clayey, grey and green sands with bands and "doggers" of brown weathering clay-ironstone and seams of phosphatic nodules [picking out erosion surfaces]. A prominent band of phosphatic nodules occurs at the base. [Mintlyn Member]. Green, glauconitic, clayey sands with abundant phosphatic nodules [Runcton Sand Member]. Grey and yellow-green, pyritic, silty sands with an indurated basal pebbly sandstone with phosphatic nodules and derived Kimmeridgian debris [Roxham Sand Member].
Definition of Lower Boundary: A down-section change from sands, with a pebbly base, to mudstones [Kimmeridge Clay Formation]. An erosion surface separates the two formations.
Definition of Upper Boundary: South of Gayton, the pebbly sands of the Carstone Formation overstep the silty and clayey sands and clean sands [Sandringham Sand Formation], resting progressively on the Roxham and Runcton members, the Mintlyn Member and finally the Leziate Member. In Northern Norfolk the upper boundary is defined by the down-section change from the clayey sands [Dersinham Formation] to incoherent, generally clean quartz sands [Leziate Member, Sandringham Sand Formation]. Beneath The Wash, the Leziate Member passes into the Claxby Ironstone Formation and the overlying Dersingham Formation passes laterally into the Tealby Formation [Gallois, 1994].
Thickness: Up to c. 50m
Geographical Limits: The Sandringham Sand Formation is confined to Norfolk and extends beneath The Wash where it apparently merges with the Claxby Ironstone Formation and Spilsby Sandstone Formation [Casey and Gallois, 1973; Wingfield et al. 1978, Gallois, 1994]. Its outcrop has been traced from the Hunstanton area South to near West Dereham.
Parent Unit: Not Applicable (-)
Previous Name(s): Sandringham Sands [Duplicate Code: Use SAS] (SNDS)
Alternative Name(s): none recorded or not applicable
Reference Section  Manor Farm, North Runcton. Casey, 1973; Casey and Gallois, 1973. 
Reference Section  Brook Farm, North Runcton. Gallois, 1994. 
Reference Section  Hunstanton Borehole. Gallois, 1994. 
Reference Section  Gayton Borehole. Gallois, 1994. 
Reference Section  800m N40W of Church Farm, Bawsey. Casey, 1973; Casey and Gallois, 1973. 
Reference Section  Western end of Galley Hill, West of Mintlyn Wood. Casey, 1973; Casey and Gallois, 1973. 
Reference Section  BGS Wash Borehole 72/77B. Winfield et al. 1978; Gallois, 1994. 
Reference Section  Marham Borehole. Gallois, 1994. 
Reference Section  Pratts Bridge Roxham, eastwards to Wissington Railway Bridge Casey, 1973; Casey and Gallois, 1973. Note that Pratt's Bridge is an insignificant (unnamed on maps) bridge carrying a track across the Cut-Off Channel southsoutheast of Roxham House. Wissington Railway Bridge carried a now dismantled railway across the same channel south of Keebles Siding, which is c.500m eastsoutheast of Station Farm. Not to be confused with bridges carrying minor roads c.500m to the west and c.200m to the east of the railway bridge. 
Whitaker, W and Jukes-Browne, A J. 1899. The geology of the borders around The Wash: including Boston and Hunstanton. Memoir of the Geological Survey of England and Wales. 
Casey, R and Gallois, R W. 1973. The Sandringham Sands of Norfolk. Proceedings of the Yorkshire Geological Society, Vol.41, 1-22. 
Casey, R 1973. The ammonite succession at the Jurassic-Cretaceous boundary in Eastern England. In Casey, R and Rawson, P F [editors], The Boreal Lower Cretaceous [Liverpool: Seel House Press.] 
Gallois, R W, 1994. The geology of the country around King's Lynn and The Wash. Memoir of the British Geological Survey, Sheet 145 and part of 129 (England and Wales). 
Wingfield, R T R, Evans, C D R, Deegan, S E and Floyd, R. 1978. Geological and geophysical survey of The Wash. Report of the Institute of Geological Sciences, 78/18, 32pp. 
Gallois, R W. 1984. The Late Jurassic to Mid Cretaceous rocks of Norfolk. Bulletin of the Geological Society of Norfolk, Vol.34, 3-64. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E129 E145 E159 E173 E146 E160